Optical switch assembly and variable optical power attenuator

Abstract

An optical assembly (14) that receives an input beam (12a) and selectively provides an adjusted beam (14a) includes an input lens assembly (24), a resonant element assembly (25), and a frequency generator (28). The resonant element assembly (25) can receive a collimated input beam (36). The frequency generator (28) selectively directs a frequency through the resonant element assembly (25) to selectively adjust the characteristics of the adjusted beam (14a) that exits the resonant element assembly (25). The frequency generator (28) includes a transducer (28a) that is coupled to the resonant element assembly (25), and a signal generator (28b) that directs an electric signal to the transducer (28a) to selectively vibrate the resonant element assembly (25).

Description

OPTICAL SWITCH ASSEMBLY AND VARIABLE OPTICAL POWER ATTENUATORRELATED APPLICATION

[0001] The present application claims priority on U.S. Provisional Patent Application No: 63 / 660,271 , filed on June 14, 2024, and entitled “Optical Switch Assembly And Variable Optical Power Attenuator”. Further, as far as permitted, the contents of U.S. Provisional Patent Application No: 63 / 660,271 are incorporated herein by reference.

[0002] Further, as far as permitted, the contents of U.S. Patent Application No: 63 / 510,619, filed on June 27, 2023, and entitled “External Cavity Laser Assembly With Stable Output Frequency” are incorporated herein by reference.BACKGROUND

[0003] Laser assemblies can be used in many fields such as, laboratories, Lidar, medical diagnostics, pollution monitoring, leak detection, analytical instruments, homeland security, aerospace, remote chemical sensing, industrial process control, and quantum computing systems.

[0004] In certain systems, it is necessary to use an optical switch to rapidly switch the light between an On Position and Off position. As non-exclusive examples, an optical switch can be used for Q-switching, signal modulation for telecommunications, or frequency control in spectroscopy.

[0005] One type of optical switch is an acousto-optic modulator (“AOM”). Unfortunately, existing acousto-optic modulators are not able to provide the combination of fast switching, thermal stability, operation over a wide spectral range, high extinction, and high contrast.SUMMARY

[0006] An optical assembly that receives an input beam and selectively provides an adjusted beam includes a resonant element assembly, and a frequency generator. The resonant element assembly includes a first resonant element thatreceives the input beam. The frequency generator selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly. The frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly.

[0007] A number of different designs for the optical assembly are provided herein. In these implementations, the optical assembly is an acousto-optic modulator (“AOM”). For example, the optical assembly can be a fiber coupled optical switch and variable power attenuator. The optical assemblies disclosed herein are uniquely designed to provide one or more of the following benefits: (i) a compact optical switch having fast switching (e.g., less than one microsecond); (ii) a high extinction-ratio (greater than ninety decibels); (iii) a variable optical power attenuator for a wide spectral range (e.g., any wavelength from 360nm to 2000nm) with independent laser output power and / or frequency control; (iv) a high diffraction efficiency and passive alignment; (v) an integrated measurement system inside the module; (vi) a flexible architecture that supports a large range of frequencies and operational wavelengths; (vii) an optical assembly having improved thermal properties; and / or (viii) an improved beam trap.

[0008] In another implementation, the optical assembly includes a resonant element assembly that receives the input beam, the resonant element assembly including a first resonant element; and a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly. In this implementation, the adjusted beam that exits the resonant element assembly is collimated; and the optical assembly has an extinction-ratio of at least eighty decibels.

[0009] In still another implementation, the optical assembly includes a resonant element assembly that receives the input beam; and a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly. In this implementation, the beam makes at least two passes through the resonant element assembly to form the adjusted beam; and wherein the adjusted beam that exits the resonant element assembly is collimated.

[0010] In yet another implementation, the optical assembly includes a resonant element assembly that receives the input beam; a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly; and an output polarization adjuster that adjusts the polarization of an element adjusted beam that exits the resonant element assembly to be the second polarization.

[0011] In still another implementation, the optical assembly includes (i) a resonant element assembly that receives the input beam; (ii) a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly; and (iii) an integrated measurement system that receives a measurement beam that exits the first resonant element.

[0012] In another implementation, the optical assembly includes (i) a resonant element assembly including a first resonant element, and an element mounting assembly that retains the first resonant element in a symmetrical fashion; (ii) a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly. In this implementation, the frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly.

[0013] Any of the implementations of the optical assembly provided herein can additionally include one or more of the following features: (i) the input beam can be collimated; (ii) an input lens assembly that collimates the input beam to create a collimated input beam that is directed at the first resonant element; (iii) an extinctionratio of at least eighty decibels; (iv) the adjusted beam exiting the resonant element assembly is collimated; (v) wherein the beam makes at least two passes through the first resonant element to form the adjusted beam; (vi) wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width is at least forty percent of the element width; (vii) wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width and the element width are selected so that the first resonant element has a narrow angle tolerance when vibrated; (viii) wherein the first transducer has a transducer width, and the first resonant element has anelement width, and wherein the transducer width and the element width are selected so that the first resonant element forms a grating when vibrated that diverges slowly; (ix) an extinction-ratio of at least ninety decibels; (x) an extinction-ratio of at least ninety-five decibels; (xi) the input beam exits the first resonant element as a first pass, element adjusted beam, and the optical assembly includes a redirector assembly which redirects the first pass, adjusted beam back into the first resonant element, and a second pass, adjusted beam exits the first resonant element; (xii) the input beam has a first polarization, and the redirector assembly includes a polarization adjuster that adjusts the polarization of the first pass, adjusted beam to be a second polarization prior to being redirected back into the first resonant element to create the second pass, adjusted beam; (xiii) an output polarization filter that receives the second pass, adjusted beam, wherein the output polarization filter transmits light at the second polarization and blocks light at the first polarization; (xiv) an input polarization filter that receives the input beam, the input polarization filter transmits light at the first polarization and blocks light at the second polarization; (xv) the input beam exits the first resonant element as a first pass, adjusted beam, and wherein the resonant element assembly includes a second resonant element that receives the first pass, adjusted beam to create a second pass adjusted beam when the second resonant element is vibrated; (xvi) the orientation of the second resonant element is inverted from the orientation of the first resonant element; (xvii) an output polarization adjuster that adjusts the polarization of the adjusted beam that exits the first resonant element to be an output polarization; (xviii) an output polarization filter that receives the beam that exits the output polarization adjuster, wherein the output polarization filter transmits light at the output polarization and blocks other polarizations; (xix) an input polarization adjuster that adjusts the polarization of the input beam that enters the resonant element assembly; (xx) the input beam has an input polarization, and further including an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the input polarization and blocks other polarizations; (xxi) an output fiber assembly that receives the adjusted beam, wherein the output fiber assembly includes an optical fiber having a fiber inlet facet that receives the adjusted beam, and a fiber cap that covers the inlet facet; (xxii) an input fiber assembly that launches the laser beam, wherein the input fiber assembly includes an optical fiber having a fiber outlet facet that launches the laser beam, and a fiber cap that covers the fiber outlet facet; (xxiii) an integrated measurement system that receives ameasurement beam that exits the resonant element assembly; (xxiv) the measurement system includes a frequency discriminator that compares two different order beams that exit the first resonant element; (xxv) the measurement system determines a first characteristic of the measurement beam; (xxvi) the first characteristic is selected from the group including power, frequency, and polarization of the measurement beam; (xxvii) the resonant element assembly includes an element mounting assembly that retains the first resonant element in a symmetrical fashion; (xxviii) the resonant element assembly includes a reflector side that reflects vibration energy in a symmetrical fashion; (xxix) the input beam is focused through the resonant element assembly; (xxx) wherein the redirector assembly includes a redirector lens assembly and a redirector, and the redirector lens assembly is telecentric; and / or (xxxi) a beam trap that receives unwanted light, the beam trap being designed to repeatedly scatter the received unwanted light in a spiral channel.

[0014] The present invention is also directed to a beam trap that receives unwanted light. The beam trap can include a trap housing that forms a spiral channel that receives the unwanted light and repeatedly scatters the unwanted light. In this implementation, the beam trap has no surfaces at normal incidence.BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:

[0016] Figure 1 is a simplified illustration of a system including a first implementation of an optical assembly;

[0017] Figure 2 is a simplified illustration of a portion of an optical assembly having features of the present invention;

[0018] Figure 3 is a simplified illustration of another implementation of the system;

[0019] Figure 4A is a simplified illustration of a portion of an inlet fiber assembly having features of the present invention;

[0020] Figure 4B is a simplified illustration of a portion of an outlet fiber assembly having features of the present invention;

[0021] Figure 5 is a simplified illustration of yet another implementation of the system;

[0022] Figure 6 is a simplified illustration of still another implementation of the system;

[0023] Figure 7 is a simplified illustration of another implementation of the system;

[0024] Figure 8 is a simplified illustration of yet another implementation of the system;

[0025] Figure 9 is a simplified illustration of still another implementation of the system;

[0026] Figure 10 is a simplified illustration of another implementation of the system;

[0027] Figure 11 is a simplified illustration of yet another implementation of the system;

[0028] Figure 12 is a simplified illustration of still another implementation of the system;

[0029] Figure 13 is a simplified illustration of another implementation of the system;

[0030] Figure 14 is a simplified illustration of yet another implementation of the system;

[0031] Figure 15 is a simplified illustration of a resonant element assembly;

[0032] Figure 16 is a simplified illustration of another implementation of the resonant element assembly;

[0033] Figure 17 is a simplified illustration of beam trap;

[0034] Figure 18 is a simplified illustration of another implementation of the beam trap;

[0035] Figure 19 is a simplified illustration of a yet another implementation of a portion of an optical assembly having features of the present invention; and

[0036] Figure 20 is a simplified illustration of still another implementation of the system.DESCRIPTION

[0037] Figure 1 is simplified illustration of a system 10 having features of the present invention. In the non-exclusive implementation of Figure 1 , the system 10includes (i) a laser assembly 12 that generates a laser beam 12a; (ii) an optical assembly 14 that selectively adjusts the laser beam 12A to selectively provide an output adjusted beam 14a; (iii) a device 16 that receives and utilizes the output adjusted beam 14a; and (iv) a system controller 18 that controls one or more of the components of the system 10. The design of each of the components of the system 10 can be varied. For example, the system 10 can be a portion of a quantum computer that is used as part of a quantum experiment, or another type of device. Further, the optical assembly 14 can be used with another type of system 10 that requires a rapidly switched or adjusted beam 14a. As non-exclusive examples, the optical assembly 14 can be used for Q-switching, signal modulation for telecommunications, or frequency control in spectroscopy.

[0038] A number of different designs for the optical assembly 14 are provided herein. In certain implementations, the optical assembly 14 is an acousto-optic modulator (“AOM”). For example, the optical assembly 14 can be a fiber coupled optical switch and variable power attenuator. One or more of the optical assemblies 14 disclosed herein are uniquely designed to provide one or more of the following benefits: (i) a compact optical switch having fast switching (e.g., less than one microsecond); (ii) continuous lasing of the laser assembly 12; (iii) a high extinctionratio (greater than ninety decibels); (iv) a variable optical power attenuator for a wide spectral range (e.g., any wavelength from 360nm to 2000nm) with independent laser output power and / or frequency control; (v) a high diffraction efficiency and passive alignment; (vi) an integrated measurement system inside the module; (vii) a flexible architecture that supports a large range of frequencies and operational wavelengths for the optical assembly 14; (viii) an optical assembly 14 having improved thermal properties; and / or (ix) an improved beam trap. In one implementation, the optical assembly 14 provides fast switching (less than one microsecond), continuous lasing of the laser assembly 12, and high contrast (greater than ninety decibels).

[0039] A number of Figures provided herein include an orientation system. For example, Figure 1 includes an orientation system that is referenced to the optical assembly 14, and that includes an X axis, a Y axis that is orthogonal to the X axis, and a Z axis that is orthogonal to the X and Y axes. It should be noted that these axes can also be referred to as the first, second and third axes.

[0040] The laser assembly 12 generates a laser beam 12a that is delivered to the optical assembly 14. The laser beam 12a can alternatively be referred to as theinput beam. The design of the laser assembly 12 can be varied to achieve the design requirements of the system 10. For example, the laser assembly 12 can be designed to generate the laser beam 12a having a wavelength in a portion of the 360 nanometer to 2000 nanometer range. In one, non-exclusive implementation, (i) a first, laser assembly 12 is an external cavity design, and the laser assembly 12 is selectively tunable over a first portion of the 360 nanometer to 2000 nanometer range; (ii) a second, laser assembly (not shown in Figure 1 ) is designed to be selectively tunable over a second portion of the 360 nanometer to 2000 nanometer range; and (iii) one or more additional laser assemblies (not shown in Figure 1 ) are designed to be selectively tunable over one or more additional portions of the 360 nanometer to 2000 nanometer range.

[0041] The laser assembly 12 can be designed to include one or more emitters 12b (only one is illustrated as a box). In one, non-exclusive implementation, each emitter 12b can be a laser diode. For example, each emitter 12b can be a short wavelength laser diode or a long wavelength laser diode. As non-exclusive examples, the laser diode can be Gallium Antimonide, Gallium arsenide, indium phosphide, gallium nitride, Indium Gallium Phosphide, Indium Gallium Nitride, Aluminum Gallium Arsenide, Aluminum Gallium Indium Phosphide, or Indium Gallium Arsenide Phosphide. Alternatively, for example, each emitter 12b can be a Quantum Cascade (“QC”) gain medium, or an interband cascade laser.

[0042] Non-exclusive examples of suitable wavelengths for the emitter 12b can include within the ultraviolet range, the visible range, the near infrared range, the infrared range, the mid-infrared range, of the far infrared range.

[0043] As a non-exclusive example, the laser assembly 12 can be designed so that the laser beam 12a has an optical power of between 0.5 to 10 watts. Stated in anotherfashion, in alternative, non-exclusive embodiments, the laser assembly 12 can be designed so that the laser beam 12a has an optical power of at least approximately 0.5, 1 , 2, 5, or 10 watts. However, optical powers of less than or greater than those values are possible.

[0044] In the non-exclusive implementation of Figure 1 , the laser assembly 12 is fiber coupled with an input fiber assembly 20 to the optical assembly 14. In this design, the laser beam 12a travels down the input fiber assembly 20 to the optical assembly 14. In the non-exclusive implementation of Figure 1 , the input fiber assembly 20 launches the laser beam 12a into the optical assembly 14. In oneimplementation, the laser beam 12a exiting the input fiber assembly 20 is diverging and is not collimated.

[0045] The optical assembly 14 receives the laser beam 12a and selectively adjusts the laser beam 12a to selectively provide the output adjusted beam 14a to the device 16. For example, the optical assembly 14 can be a compact optical switch that rapidly switches the adjusted beam 14a between an “ON Position” in which the output adjusted beam 14a is directed to the device 16, and an “OFF Position” in which very few, if any, photons are directed to the device 16. In one implementation, the laser assembly 12 is controlled to generate the laser beam 12a in a pulsed or continuous fashion, and the optical assembly 14 is controlled to selectively “switch” (direct) the output adjusted beam 14a to the device 16. As alternative, non-exclusive examples, the optical assembly 14 can be controlled to have a switch time of less than ten nanoseconds, one hundred nanoseconds, one microsecond, or twenty microseconds.

[0046] Additionally or alternatively, the optical assembly 14 can be a variable optical power attenuator (operational over a wide spectral range) with independent output power and / or frequency control of the adjusted beam 14a. For example, in certain implementations, the optical assembly 14 can be controlled to rapidly adjust the power and / or frequency of the output adjusted beam 14a.

[0047] In the non-exclusive implementation of Figure 1 , the optical assembly 14 is an acousto-optic modulator that includes (i) an assembly frame 22; (ii) an input lens assembly 24; (iii) a resonant element assembly 25 including a resonant element 26 that receives the laser beam 12a; (iv) a frequency generator 28 that selectively generates and directs a frequency through the resonant element 26; (v) a vibration absorber 29; (vi) an output lens assembly 30; and (vii) a measurement assembly 32. The design of each of these components can be varied pursuant to the teachings provided herein.

[0048] In the non-exclusive implementation of Figure 1 , the optical assembly 14 is fiber coupled with the input fiber assembly 20 to the laser assembly 12, and the optical assembly 14 is fiber coupled with an output fiber assembly 34 to the device 16. In this design, the output adjusted beam 14a travels down the output fiber assembly 34 to the device 16. It should be noted that one or both fiber assemblies 20, 34 can be a polarization maintaining optical fiber. Alternatively, one or both fiber assemblies 20, 34 can be a non-polarization maintaining optical fiber.

[0049] The assembly frame 22 can be rigid, thermally stable, support the other components of the optical assembly 14, and the assembly frame 22 can maintain the precise alignment of the components of the optical assembly 14. In the simplified implementation of Figure 1 , the assembly frame 22 is illustrated as a rectangular frame. However, other designs of the assembly frame 22 are possible. For example, in one, non-exclusive implementation, the assembly frame 22 can be designed to enclose and encircle the other components of the optical assembly 14. The assembly frame 22 can be rectangular box shaped, or have a different configuration.

[0050] Additionally and optionally, the laser assembly 10 can be designed to include one or more thermoelectric coolers (not shown) that selectively control the temperature of one or more components of the laser assembly 10.

[0051] In one implementation, the assembly frame 22 forms a controlled environment around the other components of the optical assembly 14. As alternative, non-exclusive examples, the controlled environment can be a vacuum, an inert gas, or another fluid. In one implementation, the controlled environment can be a fluid that improves the reliability of the components of the optical assembly 14. Still alternatively, for example, desiccant or another drying agent can be positioned in the assembly frame 22 to trap moisture and / or gases that could absorb laser emissions, cause corrosion, and / or to cause condensation. In a different design, the assembly frame 22 can be unsealed.

[0052] In yet another design, the assembly frame 22 can also enclose a portion or all of the laser assembly 12 and / or the device 16.

[0053] In one implementation, the input lens assembly 24 collimates the diverging laser beam 12a that is launched from the input fiber assembly 20 to create a collimated input beam 36 that is directed at the resonant element 26 at the appropriate angle. As non-exclusive examples, the input lens assembly 24 can be aspheric; conic; spherical; plano-convex; bi-convex; a meniscus lens; or double sided. Further, the input lens assembly 24 is operational in the wavelength(s) of the laser beam 12a. Alternatively, the input lens assembly 24 can be designed to focus the laser beam 12a into the resonant element 26.

[0054] The resonant element 26 receives the input beam 36 that exits input lens assembly 24, and adjusts the input beam 36. In one implementation, the input beam 36 is collimated and moves through the resonant element as a collimated beam.

[0055] For example, the resonant element 26 can be an acousto-optic crystal. In one non-exclusive implementation, the resonant element 26 is a crystal made of Tellurium dioxide (TeO2). However, other types of crystals can be utilized.

[0056] The size and shape of the resonant element 26 can be varied. For example, the resonant element 26 can be generally rectangular shaped. In one nonexclusive implementation, the resonant element 26 has a dimension along the Z axis of approximately six millimeters, a dimension along the X axis of approximately ten millimeters, and a dimension along the Y axis of approximately five millimeters. However, other shapes and / or sizes can be utilized.

[0057] The frequency generator 28 selectively generates and directs a frequency through the resonant element 26. In Figure 1, the frequency generator 28 includes a transducer 28a that is mechanically coupled (attached) to the resonant element 26, and a signal generator 28b that selectively drives the transducer 28a. In one non-exclusive implementation, the transducer 28a is a piezoelectric transducer, and the signal generator 28b is a radio frequency controller that directs an oscillating electric signal to the transducer 28a. As an example, the piezoelectric transducer 28a can be made of Lithium niobate (LiNbO3); and the radio frequency controller can generate a signal at approximately two hundred megahertz (200 MHz). However, other materials and / or other frequencies can be utilized. As non-exclusive examples, the radio frequency controller can generate a signal at approximately 50, 80, 100, 150, 175, 200, 225, 250, 300, or 1000 megahertz.

[0058] In the non-exclusive implementation of Figure 1 , when the frequency generator 28 directs a frequency through the resonant element 26, the optical assembly 14 is activated and is in the “ON Position”. In contrast, when the frequency generator 28 is not directing a frequency through the resonant element 26, the optical assembly 14 is deactivated and is in the “OFF” position. Alternatively, these positions can be switched.

[0059] In Figure 1 , when activated, the oscillating electric signal in the transducer 28a drives and causes the resonant element 26 to vibrate. This creates sound waves (e.g., an ultrasonic wave) in the resonant element 26 that changes the index of refraction in the resonant element 26 in a periodic fashion. In this implementation, when activated, the resonant element 26 diffracts the input beam 36 off the resulting periodic index modulation and the resonant element 26 functionssomewhat similar to a diffraction grating. With this design, the frequency generator 28 controls the resonant element 26 to function as an electronically controlled grating.

[0060] When activated (“ON Position”), the laser beam 12a is scattered off of the periodic index modulation of the resonant element 26 into a diffraction pattern having different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). Figure 1 illustrates when the resonant element 26 is activated, and Figure 1 only illustrates a collimated, element adjusted beam 26a (illustrated with a long dashed line), and a collimated, measurement beam 26b (illustrated with a short dashed line) exiting the resonant element 26. In this design, (i) the element adjusted beam 26a is collected by the output lens assembly 30 and focused onto the output fiber assembly 34 as the output adjusted beam 14a; (ii) the measurement beam 26b is directed to the measurement assembly 32 for analysis; and (iii) the input beam 36, the element adjusted beam 26a, and the measurement beam 26b are collimated.

[0061] In the design of Figure 1 , when activated, the majority of the laser beam 12a is scattered as the m=-1 order of diffraction, and the m=-1 order of diffraction is the element adjusted beam 26a that is directed at the output lens assembly 30 to form the output adjusted beam 14. In this implementation, the m=-1 order of diffraction can be referred to as the “first order beam” or the “element adjusted beam 26a”.

[0062] Further, in the implementation of Figure 1 , the m=0 order of diffraction is used as the measurement beam 26b and directed to the measurement assembly 32 for analysis. In this implementation, the m=0 order of diffraction beam 26b can be referred to as the “zeroth order beam” or the “measurement beam”.

[0063] When not activated (“OFF Position”), the resonant element 26 functions as a window with the collimated input beam 36 mainly being transmitted directly through the resonant element 26 as the m=0 order of diffraction, with some slight scattering.

[0064] It should be noted that when the resonant element 26 is being activated, that other orders of diffractions are being generated, even though they are not illustrated in the Figures. Additionally, it should be noted that the other orders of diffraction can be used as the element adjusted beam 26a, and / or measurement beam 26b. For example, the optical assembly 14 can be designed so that the m=+1 order of diffraction (m=+1), the m=+2 order of diffraction (m=+2), or the m=-2 order of diffraction (m=-2) beam becomes the element adjusted beam 26a, or the measurement beam 26b.

[0065] Additionally, it should be noted that when the resonant element 26 is not activated (switch “OFF Position”), the m= 0 order of diffraction beam can still be used as the measurement beam 26b. Additionally, in this design, when the resonant element 26 is not activated, a relatively small amount of light will be scattered in the resonant element 26, and a portion of that scattered light could be collected by the output lens assembly 30, focused onto the output fiber assembly 34, and directed to the device 16. This will result in a lower extinction-ratio for the optical assembly 14 of Figure 1.

[0066] With the present design, the resonant element 26 can be controlled as an optical switch that can be rapidly controlled by the frequency generator 28 to selectively direct the adjusted beam 14a to the device 16, without adjusting the laser assembly 12.

[0067] Further, it should be noted that when the resonant element 26 is activated, (i) the frequency of the m=-1 order of diffraction beam 26a is equal to the frequency of the collimated input beam 36 plus the frequency of the signal from the frequency generator 28 (input frequency + frequency of modulation), and (ii) the frequency of the m=0 order is unchanged by the frequency generator 28. In a nonexclusive example, if the frequency of the laser beam 12a is 600 Terahertz, and the frequency generator 28 is generating a signal at two hundred megahertz (200 Mhz), the resulting frequency of the m=-1 order of diffraction beam 26a is equal to 600.0002 Terahertz. With this design, the frequency generator 28 can selectively and rapidly control frequency to the resonant element 26 to selectively and rapidly adjust the frequency of the adjusted beam 14a.

[0068] Additionally, the amount of the incoming laser beam 12a that is diffracted as the m=-1 order of diffraction beam 26a, the m=0 order of diffraction beam 26b, and the other orders depends on the intensity of the sound wave generated in the resonant element 26 by the frequency generator 28. As result thereof, the frequency generator 28 can selectively control the resonant element 26 to make rapid adjustments in the intensity (power) of the adjusted beam 14a.

[0069] With this design, the optical assembly 14 is a fiber coupled optical switch and a variable power / frequency controller. Stated differently, by adjusting the RF signal sent to the transducer 28a by the signal generator 28b, the amount of diffracted light (m=-1 order) can be smoothly tuned up and down.

[0070] The absorber 29 absorbs the vibration from the resonant element 26. For example, the absorber 29 can be an absorbing material such as lead. Further, for example, the absorber 29 can be coupled to the resonant element 26.

[0071] The output lens assembly 30 receives the collimated, element adjusted beam 26a that exits the resonant element 26, and focuses and directs the output adjusted beam 14a onto an inlet facet 34a of the output fiber assembly 34. As nonexclusive examples, the output lens assembly 30 can be aspheric; conic; spherical; plano-convex; bi-convex; a meniscus lens; or double sided. Further, the output lens assembly 30 is operational in the wavelength(s) of the first order beam 26a.

[0072] The measurement assembly 32 provides information (feedback) that can be used to control the optical assembly 14 and / or the laser assembly 12 with more accuracy in a closed loop fashion to improve the accuracy of the output adjusted beam 14a. With this design, the measurement assembly 32 can be used as a feedback system that monitors one or more characteristics of the output adjusted beam 14a. For example, the measurement assembly 32 can monitor one or more of the optical power, wavelength (frequency), polarization, another characteristic of the output adjusted beam 14a, and / or the health (performance) of the laser assembly 12 and / or the optical assembly 14 to provide feedback to the system controller 18. For example, the measurement assembly 32 can include one or more sensors. With this feedback, the system controller 18 can selectively adjust one or more components of the laser assembly 10 to fine tune the characteristics of the adjusted beam 14a in a closed loop fashion. Also, the system controller 18 can monitor the health of the system 10.

[0073] The design of the measurement assembly 32 can be varied pursuant to the teachings provided herein. In the non-exclusive implementation of Figure 1 , the measurement assembly 32 provides optical diagnosis of the system 10 and includes (i) a first beam steerer 32a; (ii) a beam splitter 32b; (iii) a second beam steerer 32c; (iv) a first sensor assembly 32d; and (iv) a second sensor assembly 32e. Alternatively, the measurement assembly 32 can be designed to include more or fewer components than are illustrated in Figure 1. For example, the measurement assembly 32 can be designed without the first beam steerer 32a, the beam splitter 32b, the second beam steerer 32c, and / or the second sensor assembly 32e. Alternatively, for example, the measurement assembly 32 can be designed to include a third sensor assembly (not shown).

[0074] The first beam steerer 32a directs the measurement beam 26b at the beam splitter 32b. As a non-exclusive implementation, the first beam steerer 32a can be a knife-edge mirror or another type of reflector.

[0075] The beam splitter 32b splits the measurement beam 26b into a first sensor beam 26b1 that is directed at the first sensor assembly 32d, and a second sensor beam 26b2 that is directed at the second beam steerer 32c, and subsequently to the second sensor assembly 32e. Depending upon the design of the sensor assemblies 32d, 32e, as non-exclusive examples, the beam splitter 32b can approximately be a 10 / 90, 20 / 80, 30 / 70, 40 / 60, 50 / 50, 60 / 40, 70 / 30, 80 / 20, or 90 / 10 splitter.

[0076] The second beam steerer 32c directs the second sensor beam 26b2 at the second sensor assembly 32e. For example, the second beam steerer 32c can be a mirror or another type of element.

[0077] The first sensor assembly 32d and the second sensor assembly 32e each measures a characteristic of the measurement beam 26b that is directed through the resonant element 26. As a non-exclusive example, the first sensor assembly 32d can be a frequency sensor that measures the frequency (wavelength) of the measurement beam 26b and generates a frequency signal, and the second sensor assembly 32e can be a power sensor that measures the power (intensity) of the measurement beam 26b and generates a power signal. Alternatively, one of the sensor assemblies 32d, 32e can measure polarization or another characteristic of the measurement beam 26b.

[0078] It should be noted that the characteristics of the sensor beams 26b1 , 26b2 can be used to determine the characteristics of the measurement beam 26b. Further, the characteristics of the measurement beam 26b can be used to determine the characteristics of the output adjusted beam 14a.

[0079] In one implementation, the surfaces of the sensor assemblies 32d, 32e are slightly angled (not normal incidence) to inhibit light from being reflected back into the resonant element 26. The reflected light can adversely influence the performance of the optical assembly 14.

[0080] In certain implementations, the system controller 18 receives the feedback signal(s) (e.g., the frequency signal and the power signal) from the measurement system 32. With this design, the system controller 18 can utilize feedback signal(s) to control the optical assembly 14 and / or the laser assembly 12 ina closed loop fashion. Stated differently, the feedback from the measurement system 32 can be used in the closed loop control of the optical assembly 14 and / or the laser assembly 12.

[0081] As a non-exclusive example, the feedback from the measurement system 32 can be used to rapidly control and adjust the frequency generator 28 to reduce fluctuations in power and / or frequency of the adjusted beam 14a over time. Specifically, the output power of the measurement beam 26b can be used in feedback loop to adjust RF signal generated by the frequency generator 28 to keep the output power of the measurement beam 26b constant (or at the desired level), and the output power of the element adjusted beam 26a constant (or at the desired level). Somewhat similarly, the frequency of the measurement beam 26b can be used in a feedback loop to adjust the RF signal generated by the frequency generator 28 to keep the frequency of the measurement beam 26b constant (or at the desired level), and the frequency of the element adjusted beam 26a constant (or at the desired level).

[0082] With the present design, because the measurements are taken close to the resonant element 26, and the adjustments are made by the frequency generator 28 to the resonant element 26, these adjustments can be made very rapidly. In contrast, if the propagation time from the laser assembly 12 to the point of detection is long, then the system’s ability to cancel laser frequency fluctuations will be hampered.

[0083] As provided herein, by using an acousto-optic modulator 14 with a variable RF frequency and amplitude, both the power and frequency of the output adjusted beam 14a can be more stable than the input laser beam 12a. This control loop can have a very short propagation time, leading to better performance. In this design, the optical assembly 14 is a fiber coupled, acousto-optic modulator with integrated measurement and feedback.

[0084] It should be noted that for appropriately sized resonant element 26, a m=2 order beam (+ and - second order beam) will be present with twice the frequency shift of the first order beam. As provided herein, the second order beam can be routed to overlap with the Oth-order beam to traverse a frequency discriminator (not shown) of the measurement system 32, enabling demodulation of the photodiode signal at twice the RF drive frequency, simplifying the frequency control electronics. Alternatively, the m=+1storder beam can be picked off and used instead of a 2ndorder beam in the measurement system 32.

[0085] By using a frequency discriminator as the Optical Diagnostic (etalon, interferometer, atomic reference, vapor cell), the photodiode output can instead be used in feedback loop to adjust RF signal frequency to keep the frequency of the adjusted beam 14a constant.

[0086] Additionally, monitoring the measurement beam 26b with the measurement system 32 can inform the user about the health status of the laser assembly 12 and / or the optical assembly 14.

[0087] Alternatively, for example, the zeroth order beam or one of the other orders can be used for a different purpose, e.g., a dual output, optical assembly 14.

[0088] The system controller 18 controls the operation of one or more of the components of the system 10. For example, the system controller 18 can control the laser assembly 12 and / or the optical assembly 14. The system controller 18 can include one or more processors (not shown), and one or more electronic storage devices (not shown). The system controller 18 can be a centralized unit or a distributed system. For example, a portion of the system controller 18 can be integrated into the optical assembly 14 to control the frequency generator 28. In certain implementations, the signal generator 28b can be considered part of the system controller 18.

[0089] In one embodiment, the system controller 18 can control the electron injection current to the emitter 12b. For example, the system controller 18 can continuously direct power to the emitter 12b. Alternatively, for example, the system controller 18 can direct power in a pulsed fashion to the emitter 12b.

[0090] It should be noted that in Figure 1 , for simplicity, the input beam 36 is illustrated as being at a normal incidence angle relative to the resonant element 26. However, in most designs, the system 10 is designed so that the input beam 36 will be at a non-normal incidence angle relative to the resonant element 26. As provided herein, an effective diffraction grating is created when the frequency generator 28 vibrates the resonant element 26. This effective diffraction grating will have an acceptance angle that refers to the range of angles of the input beam 36 that will be efficiently diffracted by the grating. The acceptance angle will depend upon the RF signal frequency from the frequency generator 28, the material of the resonant element 26, and the wavelength of input beam 36. In one non-exclusive implementation, the incidence angle of the input beam 36 relative to normal on the resonant element 26 is between 0.5 degrees and one degree. However, in other implementations, theincidence angle of the input beam 36 relative to normal on the resonant element 26 can be approximately 0.5, 1 , 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more degrees.

[0091] It should also be noted that the incidence angle of the input beam 36 relative to normal on the resonant element 26 can be selected to achieve the desired exit angle of the element adjusted beam 26a and / or performance of the system 10.

[0092] Additionally, it should be noted that the resonant element assembly 25 can be designed to be a shear mode Acousto-Optic Modulator or a longitudinal mode Acousto-Optic Modulator. As provided herein, depending upon the orientation of the resonant element 26 relative to the acoustic wave propagation direction, and the position of the transducer 28a on the resonant element 26, the resonant element assembly 25 can operate in either a shear or longitudinal vibration mode.

[0093] Figure 2 is a simplified illustration of a resonant element 226 and a transducer 228a that can be used in the optical assembly 14 of Figure 1 or in subsequent designs described below. Figure 2 also illustrates the collimated, incoming laser beam 236, and the collimated, element adjusted beam 226a (illustrated with long dashes) that exits the resonant element 226 when the resonant element 226 is activated.

[0094] In the non-exclusive implementation of Figure 2, the resonant element 226 has an element width 226W measured along Z axis and the transducer 228a has a transducer width 228W also measured along Z axis. As provided herein, in certain implementations, the transducer width 228W is relatively wide. As alternative, nonexclusive examples, the transducer width 228W is at least approximately 0.1 , 1 , 2, 3, or 5 millimeters. Stated in a different fashion, as alternative, non-exclusive examples, the transducer width 228W is at least 40, 50, 60, 70, or 80 percent of the element width 226W.

[0095] With the present design, because of the large transducer width 228W, the resulting effective diffraction grating 238 (illustrated with short dashes) formed in the resonant element 226 when vibrated will be relatively large, and will have a narrow, acceptance angle tolerance 6S. As provided herein, the acceptance angle is the range of input angles for which the effect of diffraction is strong. With this design, the resonant element 226 can accept a collimated incoming laser beam 236, and the outgoing first order beam 226a will be collimated. Stated differently, use of the resonant element 226 with the large transducer 228a enables collimated traversal. In certain implementations, collimated traversal of resonant element 226 improvesdiffraction efficiency and enables passive alignment. Further, it eliminates the need for additional lenses (not shown) to focus the laser beam 236 into the resonant element 226. It should be noted that in certain designs, the ideal input angle for beam 236 is not centered around zero. For example, the desirable range of incoming angles can be QB- 6Sto 6B+ 6Sfor the Bragg angle 6Band acceptance angle (also can be referred to as angle tolerance) Qs. The Bragg angle can be the ratio of the laser beam wavelength to twice the acoustic beam wavelength.

[0096] As alternative, non-exclusive implementations, the transducer width 228W is selected so that the effective diffraction grating 238 has an acceptance angle 6Sof less than approximately 0.5, 1 , 2, 5, or 10 milliradians. As provided herein, in certain implementations, acceptance angles 9Sgreater than the divergence of the incoming beam 236 provide efficient diffraction.

[0097] In this design, the effective diffraction grating 238 is thick compared to the grating period measured along the X axis. The thick grating 238 means high diffraction efficiency occurs for narrowed range of input angles. The grating interaction width of the transducer 228a sets the diffraction efficiency angle tolerance for the incoming beam.

[0098] In certain implementations, the transducer width 228W and the element width 226W are selected so that the resonant element 226 has a narrow angle of tolerance when vibrated. Further, in certain implementations, the transducer width 228W and the element width 226W are selected so that the effective diffraction grating 238 does not significantly change throughout the resonant element 226.

[0099] Figure 3 is a simplified illustration of another implementation of a system 310 having features of the present invention. In the non-exclusive implementation of Figure 3, the system 310 includes (i) a laser assembly 312, (ii) a device 316, and (iii) a system controller 318 that are similar to the corresponding components described above and illustrated in Figure 1.

[0100] Further, the system 310 includes an optical assembly 314 that selectively adjusts the laser beam 312a generated by the laser assembly 312 to selectively provide the output adjusted beam 314a to the device 316. In Figure 3, the optical assembly 314 is similar to the optical assembly 14 described above and illustrated in Figure 1 , except that the optical assembly 314 of Figure 3 does not include the measurement assembly 32 (illustrated in Figure 1) integrated into the opticalassembly 314. Instead, in Figure 3, the m=0 order beam 326b is directed to a beam trap 340 that absorbs and / or diffuses the beam 326b to inhibit stray light from reentering the system. Stated differently, in this design, the m=-1 order beam 326a is directed to the device 316, and the m=0 order beam is discarded.

[0101] Alternatively, for example, the m=0 order beam can be used as a second output.

[0102] In Figure 3, when the resonant element 326 is being activated, other orders of diffractions are being generated, even though they are not illustrated in Figure 3. Additionally, it should be noted that the other orders of diffraction can be used as the element adjusted beam 326a. For example, the optical assembly 314 can be designed so that the m=+1 order of diffraction (m=+1), the m=+2 order of diffraction (m=+2), or the m=-2 order of diffraction (m=-2) beam becomes the element adjusted beam 326a.

[0103] It should be noted that in Figure 3, for simplicity, the input beam is illustrated as being at a normal incidence angle relative to the resonant element 326. However, similar to the implementation of Figure 1 , the system 310 is designed so that the input beam will be at a non-normal incidence angle relative to the resonant element 326.

[0104] Figure 4A is a simplified illustration of a portion of an input fiber assembly 420 that can be used in the system 10, 310 of Figures 1 or 3, or any of the other systems described herein.

[0105] In the non-exclusive implementation of Figure 4A, the input fiber assembly 420 includes an optical fiber 420a having a fiber outlet facet 420b, and a fiber cap 420c including a cap outlet facet 420d. In this design, the fiber cap 420c covers the fiber outlet facet 420b. With this design, the fiber cap 420c influences how the laser beam 412a is launched (exits) the input fiber assembly 420. For example, the fiber cap 420c can reduce the optical damage generated on the fiber outlet facet 420b because the cap outlet facet 420d is larger.

[0106] It should be noted that the use of the fiber cap 420c on the input fiber assembly 420 can improve performance by reducing the amount of light reflected back to laser assembly 12, 312 of Figures 1 and 3.

[0107] Figure 4B is a simplified illustration of a portion of an output fiber assembly 434 that can be used in the system 10, 310 of Figures 1 or 3, or any of the other systems described herein.

[0108] In the non-exclusive implementation of Figure 4B, the output fiber assembly 434 includes an optical fiber 434b having the fiber inlet facet 434a, and a fiber cap 434c including a cap inlet facet 434d. In this design, the fiber cap 434c covers the fiber outlet facet 434a. With this design, the fiber cap 434c influences how the adjusted beam 414a enters the fiber inlet facet 434a, and how any light (reflected beam) 435 is reflected from the output fiber assembly 434. For example, the fiber cap 434c can reduce the optical damage generated on the fiber inlet facet 434a because the cap inlet facet 434d is larger, and the fiber cap 434c can cause the reflected beam 435 to be defocused, and not return to the resonant element 326 (illustrated in Figure 3). Stated differently, the fiber cap 434c allows for higher power handling, and the optical fiber assembly 434 can tolerate higher power without damaging the optical fiber 434b.

[0109] It should be noted that the use of the fiber cap 434c at the input and output can improve return loss and power handling.

[0110] Figure 5 is a simplified illustration of another implementation of a system 510 having features of the present invention. In the non-exclusive implementation of Figure 5, the system 510 includes (i) a laser assembly 512, (ii) a device 516, and (iii) a system controller 518 that are somewhat similar to the corresponding components described above and illustrated in Figure 1.

[0111] Further, the system 510 includes an optical assembly 514 that selectively adjusts the laser beam 512a generated by the laser assembly 512 to selectively provide the output adjusted beam 514a to the device 516. In Figure 5, the optical assembly 514 is somewhat similar to the optical assembly 14 described above and illustrated in Figure 1 , except that the optical assembly 514 of Figure 5 is designed to have a dual pass architecture. This dual pass architecture allows the optical assembly 514 to have a high extinction-ratio. As used herein, the “extinction ratio” references the difference between the energy directed to the device 516 when the optical assembly 514 is activated (On Position) versus the energy directed to the device 516 when the optical assembly 514 is not activated (OFF Position). Stated differently, the “extinction ratio” references the difference between the intensity of the output adjusted beam 514a when the optical assembly 514 is activated (On Position) versus the intensity of the output adjusted beam 514a when the optical assembly 514 is not activated (OFF Position). As used herein, in alternative implementations, a highextinction-ratio shall mean at least 80, 85, 90, or 95 decibels. This means that in the “OFF Position”, very few, if any photons will reach the device 516.

[0112] In Figure 5, the optical assembly 514 is an acousto-optic modulator that includes (i) an assembly frame 522; (ii) an input lens assembly 524; (iii) a resonant element assembly 525 including the resonant assembly 526 that receives the laser beam 512a; (iv) a frequency generator 528 that selectively generates and directs a frequency through the resonant element 526; (v) a vibration absorber 529; (vi) an output lens assembly 530; and (vii) a measurement assembly 532 that are somewhat similar to the corresponding components described above and illustrated in Figure 1 .

[0113] However, in Figure 5, the optical assembly 514 additionally includes an input polarization filter 542, a redirector assembly 544, a first beam director 546, a second beam director 548, and an output polarization filter 550. The design of each of these components can be varied pursuant to the teachings provided herein. Further, the optical assembly 514 can be designed to include more or fewer components than are illustrated in Figure 5. It should be noted that the input polarization filter 542 and / or the output polarization filter 550 can alternatively be referred to as the first or second polarization filter.

[0114] In the implementation of Figure 5, the laser assembly 512 generates the laser beam 512a that is launched from the input fiber assembly 520 at the inlet lens assembly 524. In this design, the laser assembly 512 is designed so that the laser beam 512a has first polarization. The “first polarization” can alternatively be referred to as the “input polarization”.

[0115] In Figure 5, after the laser beam 512a is collimated by the inlet lens assembly 524, it is directed at the input polarization filter 542. In one implementation, the input polarization filter 542 is designed to transmit light having the first polarization and block light that is not at the first polarization. With this design, the collimated laser beam 512a is transmitted through the input polarization filter 542 as the collimated input beam 536. Subsequently, the collimated input beam 536 is directed at the resonant element 526.

[0116] When the frequency generator 528 directs a frequency through the resonant element 526, the optical assembly 514 is activated and is in the “ON Position”. In contrast, when the frequency generator 528 is not directing a frequency through the resonant element 526, the optical assembly 514 is deactivated and is in the “OFF Position”.

[0117] As provided above, the optical assembly 514 of Figure 5 is designed to have a dual pass architecture. In this implementation, the beam makes two, collimated passes through the resonant element 526, and the polarization of the beam is rotated to improve the extinction-ratio of the optical assembly 514.

[0118] In the first pass through the resonant element 526, when activated, the collimated input beam 536 is scattered into a diffraction pattern having different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). Figure 5 illustrates when the resonant element 526 is activated, and Figure 5 illustrates the first pass, element adjusted beam 526a1 (illustrated with a long dashed line), and the measurement beam 526b exiting the resonant element 526 during the first pass. In this example, the first pass, m=-1 order of diffraction is the first pass, element adjusted beam 526a1 , and a first pass, m=0 order of diffraction is the measurement beam 526b. The first pass, m=-1 order of diffraction 526a1 can alternatively be referred to as the “first pass, first order beam” or the “first pass, adjusted beam”; and the first pass, m=0 order of diffraction 526b can be referred to as the “first pass, zeroth order beam” or the “measurement beam”.

[0119] Alternatively, for example, the optical assembly 514 can be designed so that the m=+1 order of diffraction (m=+1), the m=+2 order of diffraction (m=+2), or the m=-2 order of diffraction (m=-2) beam becomes the first pass, element adjusted beam 526a1 , or the measurement beam 526b.

[0120] In Figure 5, when not activated, the resonant element 526 functions as a window with the collimated input beam 536 mainly being transmitted directly through the resonant element 526, with some slight scattering.

[0121] In the non-exclusive implementation of Figure 5, when activated, the majority of the laser beam 512a is scattered as the first pass, m=-1 order of diffraction 526a1 that is directed at the redirector assembly 544. In one design, the redirector assembly 544 (i) receives the first pass, adjusted beam 526a1 ; (ii) rotates the polarization of the first pass, adjusted beam 526a1 to have a second polarization which is different from the first polarization; and (iii) redirects a redirected beam 526ar (illustrated with dot dashed line) back into the resonant element 526 for a second pass through the resonant element 526 slightly offset from the first pass. The second polarization can alternatively be referred to as the “output polarization”.

[0122] A number of alternative, non-exclusive designs of the redirector assembly 544 are provided herein. In the implementation of Figure 5, the redirector assembly 544 includes a polarization adjuster 544a, a redirector lens assembly 544b,and a redirector 544c. The design of each of these components can be varied pursuant to the teachings provided herein. Alternatively, the redirector assembly 544 can be designed to include more or fewer components.

[0123] In one implementation, the polarization adjuster 544a receives the first pass, element adjusted beam 526a1 , and directs that beam 526a1 at the redirector lens assembly 544b, which focuses the light on the redirector 544c. Next, the light that reflects off of the redirector 544c, is collimated by the redirector lens assembly 544b, and directed through the polarization adjuster 544a a second time. Subsequently, the polarization adjuster 544a directs the collimated, rotated, redirected beam 526ar at the resonant element 526 for the second pass through the resonant element 526. The polarization adjuster 544a can be referred to as an “output polarization adjuster”.

[0124] It should be noted that the polarization adjuster 544a can be varied to achieve the desired performance of the optical assembly 514. As non-exclusive examples, the first polarization can differ from the second polarization by plus or minus 90 degrees. In the specific example of Figure 5, the light makes two passes through the polarization adjuster 544a. In one example, if the polarization adjuster 544a rotates the polarization forty-five degrees during each pass, the first polarization will differ from the second polarization by ninety degrees.

[0125] Still alternatively, the redirector assembly 544 can be designed so that the beam makes only one pass through the polarization adjuster 544a.

[0126] In one, non-exclusive implementation, the polarization adjuster 544a can be optical prism, such as a Fresnel rhomb. The Fresnel rhomb is operational over a wide spectral range, and can be positioned forty-five degrees out of plane. In this implementation, the polarization adjuster 544a can be designed to rotate and transform the polarization of the first pass, element adjusted beam 526a1 which has the first polarization, to the redirected beam 526ar having the second polarization which is different from the first polarization.

[0127] The redirector lens assembly 544b (i) focuses the first pass, adjusted beam 526a 1 that has passed the first time through the polarization adjuster 544a at the redirector 544c, (ii) collimates the beam reflected by the redirector 544c, and (iii) directs that collimated beam at the polarization adjuster 544a for a second pass through the polarization adjuster 544a. As a non-exclusive example, the redirectorlens assembly 544b can be a cat’s eye lens, or another type of lens. Further, the redirector lens assembly 544b is operational in the wavelength(s) of the laser beam.

[0128] The redirector 544c can be a mirror or another type of reflective element. In a specific example, the redirector 544c can be a cat’s eye mirror.

[0129] As provided herein, the redirector assembly 544 rotates the polarization of the first pass, adjusted beam 526a1 , to create a redirected beam 526ar having a second polarization that is directed back into the resonant element 526 for the second pass through the resonant element 526 slightly offset (e.g., along the X axis) from the first pass.

[0130] Subsequently, the redirected beam 526ar that enters the resonant element 526 during the second pass is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 5, (i) a second pass, element adjusted beam 526a2 (illustrated with divided line) that exits the resonant element 526 is directed at the first beam director 546. In this implementation, the second pass, element adjusted beam 526a2 is the second pass, m=-1 order of diffraction 526a2. This beam can alternatively be referred to as the “second pass, first order beam” or the “second pass, adjusted beam”. Alternatively, for example, the optical assembly 514 can be designed so that the m=+1 order of diffraction (m=+1 ), the m=+2 order of diffraction (m=+2), or the m=-2 order of diffraction (m=-2) beam becomes the second pass, element adjusted beam 526a2.

[0131] The first beam director 546 steers the second pass, element adjusted beam 526a2 at the second beam director 548; (iii) the second beam director 548 steers the second pass, element adjusted beam 526a2 at the output polarization filter 550. In this design, (i) each beam director 546, 548 can be reflector, e.g., a knife-edge mirror; and (ii) the output polarization filter 550 can transmit light at the second polarization and block light at other polarizations. The light that is transmitted through the output polarization filter 550 is focused by the output lens assembly 530 onto the output fiber assembly 534 as the adjusted beam 514a.

[0132] As provided above, the dual pass, polarization rotation design of Figure 5 allows the optical assembly 514 to have a high extinction-ratio. This means that in the “OFF Position”, very few, if any photons will reach the device 516. In the “OFF Position”, the bulk of the input beam 536 is transmitted through the resonant element 526, and a small amount of input beam 536 can be scattered from the resonant element 526 to the first beam director 546, the second beam director 548, and thenthe output polarization filter 550. Importantly, this scattered light will still have the first polarization because this light has not passed though the polarization adjuster 544a. As a result thereof, this scattered light will be blocked by the output polarization filter 550.

[0133] Further, in the “OFF” position, a small amount of input beam 536 can be scattered from the resonant element 526 to redirector assembly 544, have its polarization rotated and returned to the resonant element 526 as a low intensity, redirected beam. However, because the resonant element 526 is “OFF”, the majority of this low intensity, redirected beam will be transmitted through as the zeroth order beam and miss the first beam director 546, the second beam director 548, and then the second polarization filter 550. In this design, only a small amount of the low intensity redirected beam will scattered back to the first beam director 546, the second beam director 548, and then the second polarization filter 550. As a result thereof, in the “OFF” position, very few, if any photons will reach the device 516.

[0134] Additionally, the optical assembly 514 of Figure 5 also includes the measurement assembly 532 integrated into the optical assembly 514 similar to the design of Figure 1. However, in Figure 5, the measurement assembly 532 includes (i) a first beam trap 540a that captures any of the first sensor beam 526b 1 that is reflected off of the first sensor assembly 532d, and (ii) a second beam trap 540b that captures any of the second sensor beam 526b2 that is reflected off of the second sensor assembly 532e. The beam trap 540a, 540b absorb and / or diffuse the beams 526b1 , 526b2 to inhibit stray light from reentering the system. It should be noted that the beam traps 540a, 540b are optional, or the two beam traps 540a, 540b can be replaced with a single trap.

[0135] It should be noted that in Figure 5, for simplicity, the input beam 536 is illustrated as being at a normal incidence angle relative to the resonant element 526. However, similar to the implementation of Figure 1 , the system 510 can be designed so that the input beam 536 will be at a non-normal incidence angle relative to the resonant element 526.

[0136] Figure 6 is a simplified illustration of yet another implementation of a system 610 having features of the present invention. In the non-exclusive implementation of Figure 6, the system 610 includes (i) a laser assembly 612, (ii) a device 616, and (iii) a system controller 618 that are similar to the corresponding components described above and illustrated in Figure 1.

[0137] Further, the system 610 includes an optical assembly 614 that selectively adjusts the laser beam 612a generated by the laser assembly 612 to selectively provide the output adjusted beam 614a to the device 616. In Figure 6, the optical assembly 614 has a dual pass architecture that allows the optical assembly 614 to have a high extinction-ratio similar to the optical assembly 514 described above and illustrated in Figure 5.

[0138] In Figure 6, the optical assembly 614 is an acousto-optic modulator that includes (i) an assembly frame 622; (ii) an input lens assembly 624; (iii) a resonant element 626 that receives the collimated input beam 636; (iv) a frequency generator 628 that selectively generates and directs a frequency through the resonant element 626; (v) a vibration absorber 629; (vi) an output lens assembly 630; (vii) a measurement assembly 632; (viii) an inlet polarization filter 642; (ix) a first beam director 646; (x) a second beam director 648; and (xi) an outlet polarization filter 650 that are similar to the corresponding components described above and illustrated in Figure 5.

[0139] However, in Figure 6, the optical assembly 614 includes a redirector assembly 644 that is slightly different from the implementation of Figure 5. More specifically, in Figure 6, the polarization adjuster 644a is a waveplate, the redirector 644c is a corner cube, and the redirector lens assembly 544b (illustrated in Figure 5) has been eliminated. For example, the polarization adjuster 644a can be a quarter, or half waveplate. Further, the corner cube 644c can be hollow or filled. In Figure 6, the redirector assembly 644 is designed so that the beam makes only one pass through the polarization adjuster 644a.

[0140] Moreover, in Figure 6, the polarization adjuster 644a receives the collimated first pass, element adjusted beam 626a1 , and directs the collimated beam 626a1 at the redirector 644c. Next, the redirector 644c directs the collimated, rotated, redirected beam 626ar at the resonant element 626 for the second pass through the resonant element 626 to create the second pass, element adjusted beam 626a2.

[0141] Thus, similar to the implementation of Figure 5, the redirector assembly 644 rotates the polarization of the first pass, adjusted beam 626a1 , to create a redirected beam 626ar having a second polarization that is directed back into the resonant element 626 for the second pass through the resonant element 626 slightly offset (e.g., along the X axis) from the first pass.

[0142] Subsequently, the redirected beam 626ar that enters the resonant element 626 during the second pass is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 6, (i) the second pass, element adjusted beam 626a2 (illustrated with divided line) that exits the resonant element 626 is directed at the first beam director 646; (ii) the first beam director 646 steers the second pass, adjusted beam 626a2 at the second beam director 648; and (iii) the second beam director 648 steers the second pass, adjusted beam 626a2 at the outlet polarization filter 650. The light that is transmitted through the outlet polarization filter 650 is focused by the output lens assembly 630 onto the output fiber assembly 634 as the adjusted beam 614a.

[0143] It should be noted that in Figure 6, for simplicity, the input beam 636 is illustrated as being at a normal incidence angle relative to the resonant element 626. However, similar to the implementation of Figure 1 , the system 610 can be designed so that the input beam 636 will be at a non-normal incidence angle relative to the resonant element 626.

[0144] Figure 7 is a simplified illustration of still another implementation of a system 710 having features of the present invention. In the non-exclusive implementation of Figure 7, the system 710 includes (i) a laser assembly 712, (ii) a device 716, and (iii) a system controller 718 that are similar to the corresponding components described above and illustrated in Figure 1.

[0145] Further, the system 710 includes an optical assembly 714 that selectively adjusts the laser beam 712a generated by the laser assembly 712 to selectively provide the output adjusted beam 714a to the device 716. In Figure 7, the optical assembly 714 has a dual pass architecture that allows the optical assembly 714 to have a high extinction-ratio similar to the optical assembly 514 described above and illustrated in Figure 5.

[0146] In Figure 7, the optical assembly 714 is an acousto-optic modulator that includes (i) an assembly frame 722; (ii) an input lens assembly 724; (iii) a resonant element 726 that receives the collimated input beam 736; (iv) a frequency generator 728 that selectively generates and directs a frequency through the resonant element 726; (v) a vibration absorber 729; (vi) an output lens assembly 730; (vii) a measurement assembly 732; (viii) an inlet polarization filter 742; (ix) a first beam director 746; (x) a second beam director 748; and (xi) an outlet polarization filter 750that are similar to the corresponding components described above and illustrated in Figure 5.

[0147] However, in Figure 7, the optical assembly 714 includes a redirector assembly 744 that is slightly different from the implementation of Figure 5. More specifically, in Figure 7, the redirector assembly 744 again includes a polarization adjuster 744a, a redirector lens assembly 744b similar to the redirector lens assembly 544b illustrated in Figure 5, and a redirector 744c similar to the redirector 544C illustrated in Figure 5. However, in Figure 7, the polarization adjuster 744a is a waveplate similar to the polarization adjuster 644a described above and illustrated in Figure 6. For example, the polarization adjuster 744a can be a quarter, or half waveplate. In Figure 7, the redirector assembly 744 is designed so that the beam makes only one pass through the polarization adjuster 744a.

[0148] Moreover, in Figure 7, the polarization adjuster 744a receives the collimated first pass, element adjusted beam 726a1 , and the redirector lens assembly 744b focuses the collimated beam 726a1 at the redirector 744c. Next, the redirector 744c directs the beam at the redirector lens assembly 744b, and the redirector lens assembly 744b directs the collimated, rotated, redirected beam 726ar at the resonant element 726 for the second pass through the resonant element 726.

[0149] Thus, similar to the implementation of Figure 5, the redirector assembly 744 rotates the polarization of the first pass, element adjusted beam 726a1 , to create a redirected beam 726ar having a second polarization that is directed back into the resonant element 726 for the second pass through the resonant element 726 slightly offset (e.g., along the X axis) from the first pass.

[0150] Subsequently, the redirected beam 726ar that enters the resonant element 726 during the second pass is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 7, (i) the second pass, element adjusted beam 726a2 (illustrated with divided line) that exits the resonant element 726 is directed at the first beam director 746; (ii) the first beam director 746 steers the second pass, element adjusted beam 726a2 at the second beam director 748; and (iii) the second beam director 748 steers the second pass, element adjusted beam 726a2 at the outlet polarization filter 750. The light that is transmitted through the outlet polarization filter 750 is focused by the output lens assembly 730 onto the output fiber assembly 734 as the adjusted beam 714a.

[0151] It should be noted that in Figure 7, for simplicity, the input beam 736 is illustrated as being at a normal incidence angle relative to the resonant element 726. However, similar to the implementation of Figure 1 , the system 710 can be designed so that the input beam 736 will be at a non-normal incidence angle relative to the resonant element 726.

[0152] Figure 8 is a simplified illustration of still another implementation of a system 810 having features of the present invention. In the non-exclusive implementation of Figure 8, the system 810 includes (i) a laser assembly 812, (ii) a device 816, and (iii) a system controller 818 that are similar to the corresponding components described above and illustrated in Figure 1.

[0153] Further, the system 810 includes an optical assembly 814 that selectively adjusts the laser beam 812a generated by the laser assembly 812 to selectively provide the adjusted beam 814a to the device 816. In Figure 8, the optical assembly 814 has a dual pass architecture that allows the optical assembly 814 to have a high extinction-ratio similar to the optical assembly 514 described above and illustrated in Figure 5.

[0154] In Figure 8, the optical assembly 814 is an acousto-optic modulator that includes (I) an assembly frame 822; (ii) an input lens assembly 824; (iii) a resonant element 826 that receives the collimated input beam 836; (iv) a frequency generator 828 that selectively generates and directs a frequency through the resonant element 826; (v) a vibration absorber 829; (vi) an output lens assembly 830; (vii) a measurement assembly 832; (viii) an inlet polarization filter 842; (ix) a first beam director 846; (x) a second beam director 848; and (xi) an outlet polarization filter 850 that are similar to the corresponding components described above and illustrated in Figure 5.

[0155] However, in Figure 8, the optical assembly 814 includes a redirector assembly 844 that is slightly different from the implementation of Figure 7. More specifically, in Figure 8, the redirector assembly 844 again includes a polarization adjuster 844a, a redirector lens assembly 844b similar to the redirector lens assembly 744b illustrated in Figure 7, and a redirector 844c similar to the redirector 744C illustrated in Figure 7. However, in Figure 8, the polarization adjuster 844a is a waveplate (e.g., quarter waveplate) that is designed so that the beam makes two passes through the polarization adjuster 844a.

[0156] Moreover, in Figure 8, the polarization adjuster 844a receives the collimated first pass, element adjusted beam 826a1 , and the redirector lens assembly 844b focuses the collimated beam 826a1 at the redirector 844c. Next, the redirector 844c directs the beam at the redirector lens assembly 844b, and the redirector lens assembly 844b directs the beam for a second pass through the polarization adjuster 844a, which directs the collimated, rotated, redirected beam 826ar at the resonant element 826 for the second pass through the resonant element 826.

[0157] Thus, similar to the implementation of Figure 5, the redirector assembly 844 rotates the polarization of the first pass, element adjusted beam 826a1 , to create a redirected beam 826ar having a second polarization that is directed back into the resonant element 826 for the second pass through the resonant element 826 slightly offset (e.g., along the X axis) from the first pass.

[0158] Subsequently, the redirected beam 826ar that enters the resonant element 826 during the second pass is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 8, (i) the second pass, element adjusted beam 826a2 (illustrated with divided line) that exits the resonant element 826 is directed at the first beam director 846; (ii) the first beam director 846 steers the second pass, element adjusted beam 826a2 at the second beam director 848; and (iii) the second beam director 848 steers the second pass, adjusted beam 826a2 at the output polarization filter 850. The light that is transmitted through the second polarization filter 850 is focused by the output lens assembly 830 onto the output fiber assembly 834 as the adjusted beam 814a.

[0159] It should be noted that in Figure 8, for simplicity, the input beam 836 is illustrated as being at a normal incidence angle relative to the resonant element 826. However, similar to the implementation of Figure 1 , the system 810 can be designed so that the input beam 836 will be at a non-normal incidence angle relative to the resonant element 826.

[0160] Figure 9 is a simplified illustration of yet another implementation of a system 910 having features of the present invention. In the non-exclusive implementation of Figure 9, the system 910 includes (i) a laser assembly 912, (ii) a device 916, and (iii) a system controller 918 that are similar to the corresponding components described above and illustrated in Figure 1.

[0161] Further, the system 910 includes an optical assembly 914 that selectively adjusts the laser beam 912a generated by the laser assembly 912 toselectively provide the adjusted beam 914a to the device 916. In Figure 9, the optical assembly 914 has a dual pass architecture that allows the optical assembly 914 to have a high extinction-ratio similar to the optical assembly 514 described above and illustrated in Figure 5.

[0162] In Figure 9, the optical assembly 914 is an acousto-optic modulator that includes (i) an assembly frame 922; (ii) an input lens assembly 924; (iii) a resonant element 926 that receives the collimated input beam 936; (iv) a frequency generator 928 that selectively generates and directs a frequency through the resonant element 926; (v) a vibration absorber 929; (vi) an output lens assembly 930; (vii) a measurement assembly 932; (viii) an inlet polarization filter 942; (ix) a first beam director 946; (x) a second beam director 948; and (xi) an outlet polarization filter 950 that are similar to the corresponding components described above and illustrated in Figure 6.

[0163] However, in Figure 9, the optical assembly 914 includes a redirector assembly 944 that is slightly different from the implementation of Figure 6. More specifically, in Figure 9, the redirector assembly 944 again includes a polarization adjuster 944a somewhat similar to the polarization adjuster 644a illustrated in Figure 6, and a redirector 944c that is a retro-reflector, such as a porro prism (e.g., hollow or filled, ninety degree or forty-five degree apex). However, in Figure 9, the polarization adjuster 944a is a waveplate (e.g., quarter waveplate) that is designed so that the beam makes two passes through the polarization adjuster 944a.

[0164] Moreover, in Figure 9, the polarization adjuster 944a receives the collimated first pass, element adjusted beam 926a1 , and directs that collimated beam at the redirector 944c. Next, the redirector 944c directs the collimated, rotated, redirected beam 926ar at the polarization adjuster 944a and then resonant element 926 for the second pass through the polarization adjuster 944a and the resonant element 926.

[0165] Thus, similar to the implementation of Figure 5, the redirector assembly 944 rotates the polarization of the first pass, adjusted beam 926a1 , to create a redirected beam 926ar having a second polarization that is directed back into the resonant element 926 for the second pass through the resonant element 926 slightly offset (e.g., along the X axis) from the first pass.

[0166] Subsequently, the redirected beam 926ar that enters the resonant element 926 during the second pass is diffracted into the different orders of diffraction(m=... , -2, -1 , 0, +1 , +2, ...). In Figure 9, (i) the second pass, element adjusted beam 926a2 (illustrated with divided line) that exits the resonant element 926 is directed at the first beam director 946; (ii) the first beam director 946 steers the second pass, element adjusted beam 926a2 at the second beam director 948; and (iii) the second beam director 948 steers the second pass, element adjusted beam 926a2 at the second polarization filter 950. The light that is transmitted through the output polarization filter 950 is focused by the output lens assembly 930 onto the output fiber assembly 934 as the adjusted beam 914a.

[0167] It should be noted that in Figure 9, for simplicity, the input beam 936 is illustrated as being at a normal incidence angle relative to the resonant element 926. However, similar to the implementation of Figure 1 , the system 910 can be designed so that the input beam 936 will be at a non-normal incidence angle relative to the resonant element 926.

[0168] Figure 10 is a simplified illustration of still another implementation of a system 1010 having features of the present invention. In the non-exclusive implementation of Figure 10, the system 1010 includes (i) a laser assembly 1012, (ii) a device 1016, and (iii) a system controller 1018 that are similar to the corresponding components described above and illustrated in Figure 1.

[0169] Further, the system 1010 includes an optical assembly 1014 that selectively adjusts the laser beam 1012a generated by the laser assembly 1012 to selectively provide the adjusted beam 1014a to the device 1016. In Figure 10, the optical assembly 1014 has a dual pass architecture that allows the optical assembly 1014 to have a high extinction-ratio similar to the optical assembly 514 described above and illustrated in Figure 5. Further, the system 1010 of Figure 10 includes a periscope, beamsplitter optics assembly 1052 that is described below.

[0170] In Figure 10, the optical assembly 1014 is an acousto-optic modulator that includes (i) an assembly frame 1022; (ii) an input lens assembly 1024; (iii) a resonant element 1026 that receives the collimated input beam 1036; (iv) a frequency generator 1028 that selectively generates and directs a frequency through the resonant element 1026; (v) a vibration absorber 1029; (vi) an output lens assembly 1030; (vii) a measurement assembly 1032; (viii) an input polarization filter 1042; and (ix) an output polarization filter 1050 that are similar to the corresponding components described above and illustrated in Figure 6.

[0171] However, in Figure 10, the optical assembly 1014 includes a redirector assembly 1044 that is slightly different from the implementation of Figure 6. More specifically, in Figure 10, the redirector assembly 1044 includes (i) a polarization adjuster 1044a that is a waveplate (e.g., a quarter waveplate) somewhat similar to polarization adjuster 644a of Figure 6, and (ii) a redirector 1044c is a mirror or other reflector. In Figure 10, the redirector assembly 1044 is designed so that the beam makes two passes through the polarization adjuster 1044a.

[0172] Specifically, in Figure 10, the polarization adjuster 1044a receives the collimated first pass, element adjusted beam 1026a1 (e.g., m=-1 order beam), and directs the collimated beam 1026a1 at the redirector 1044c. Next, the redirector 1044c directs the collimated beam back along the same path at the polarization adjuster 1044a for a second pass through the polarization adjuster 1044a. Subsequently, the collimated, rotated, redirected beam 1026ar is directed at the resonant element 1026 for the second pass through the resonant element 1026.

[0173] Thus, similar to the implementation of Figure 6, the redirector assembly 1044 rotates the polarization of the first pass, element adjusted beam 1026a1 , to create a redirected beam 1026ar having a second polarization that is directed back into the resonant element 1026 for the second pass through the resonant element 1026. However, in the implementation of Figure 10, the path (first pass) of the input beam 1036 through the resonant element 1026, and the path (second pass) of the redirected beam 1026ar through the resonant element 1026 are overlapping and not offset.

[0174] In the implementation of Figure 10, because of the overlapping paths, the first director 646 (illustrated in Figure 6), and the second director 648 (illustrated in Figure 6) have been replaced with the periscope, beamsplitter optics assembly 1052. In this design, the beamsplitter optics assembly 1052 includes a polarization beamsplitter 1052a that transmits light at the first polarization, and reflects light at the second polarization. With this design, the input beam 1036 is transmitted through the beamsplitter 1052a, and the second pass, element adjusted beam 1026a2 is reflected by the beamsplitter 1052a.

[0175] In Figure 10, the redirected beam 1026ar that enters the resonant element 1026 during the second pass is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 10, (i) the second pass, element adjusted beam 1026a2 (illustrated with divided line) that exits the resonant element 1026 is directedat the periscope, beamsplitter optics assembly 1052; and (ii) the periscope, beamsplitter optics assembly 1052 steers the second pass, element adjusted beam 1026a2 at the output polarization filter 1050. The light that is transmitted through the output polarization filter 1050 is focused by the output lens assembly 1030 onto the output fiber assembly 1034 as the adjusted beam 1014a.

[0176] It should be noted that in Figure 10, for simplicity, the input beam 1036 is illustrated as being at a normal incidence angle relative to the resonant element 1026. However, similar to the implementation of Figure 1 , the system 1010 can be designed so that the input beam 1036 will be at a non-normal incidence angle relative to the resonant element 1026.

[0177] Figure 11 is a simplified illustration of yet another implementation of a system 1 110 having features of the present invention. In the non-exclusive implementation of Figure 11 , the system 1110 includes (i) a laser assembly 11 12, (ii) a device 11 16, and (iii) a system controller 1118 that are similar to the corresponding components described above and illustrated in Figure 1.

[0178] Further, the system 1110 includes an optical assembly 1114 that selectively adjusts the laser beam 1112a generated by the laser assembly 1 112 to selectively provide the output adjusted beam 1114a to the device 11 16. In Figure 11 , the optical assembly 1 114 has a dual pass architecture that allows the optical assembly 1114 to have a high extinction-ratio similar to the optical assembly 514 described above and illustrated in Figure 5.

[0179] In Figure 11 , the optical assembly 1114 is an acousto-optic modulator that includes (i) an assembly frame 1122; (ii) an input lens assembly 1124; (iii) a resonant element 1126 that receives the collimated input beam 1136; (iv) a frequency generator 1 128 that selectively generates and directs a frequency through the resonant element 1126; (v) a vibration absorber 1129; (vi) an output lens assembly 1130; (vii) a measurement assembly 1132; (viii) an input polarization filter 1142; (ix) a periscope, beamsplitter optics assembly 1152, and (x) an output polarization filter 1150 that are similar to the corresponding components described above and illustrated in Figure 10.

[0180] However, in Figure 11 , the optical assembly 11 14 includes a redirector assembly 1144 that is slightly different from the implementation of Figure 10. More specifically, in Figure 11 , the redirector assembly 1 144 includes (i) a polarization adjuster 1144a that can be optical prism, such as a Fresnel rhomb, similar topolarization adjuster 544a of Figure 5, and (ii) a redirector 1144c is a mirror or other reflector similar to the redirector 1044c of Figure 10. In Figure 11 , the redirector assembly 1144 is designed so that the beam makes two passes through the polarization adjuster 1144a.

[0181] Specifically, in Figure 11 , the polarization adjuster 1144a receives the collimated first pass, element adjusted beam 1126a1 , and directs the collimated beam 1126a1 at the redirector 1144c. Next, the redirector 1144c directs the collimated beam back along the same path at the polarization adjuster 1 144a for a second pass through the polarization adjuster 1144a. Subsequently, the collimated, rotated, redirected beam 1126ar is directed at the resonant element 1126 for the second pass through the resonant element 1126.

[0182] Similar to the implementation of Figure 10, the redirector assembly 1144 rotates the polarization of the first pass, adjusted beam 1126a1 , to create a redirected beam 1126ar having a second polarization that is directed back into the resonant element 1126 for the second pass through the resonant element 1 126. In the implementation of Figure 11 , the path (first pass) of the input beam 1136 through the resonant element 1126, and the path (second pass) of the redirected beam 1126ar through the resonant element 1126 are overlapping and not offset.

[0183] In Figure 11 , the redirected beam 1126ar that enters the resonant element 1126 during the second pass is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 11 , (i) the second pass, element adjusted beam 1126a2 (illustrated with divided line) that exits the resonant element 1126 is directed at the periscope, beamsplitter optics assembly 1152; and (ii) the periscope, beamsplitter optics assembly 1152 steers the second pass, element adjusted beam 1126a2 at the second polarization filter 1150. The light that is transmitted through the output polarization filter 1150 is focused by the output lens assembly 1130 onto the output fiber assembly 1134 as the adjusted beam 1114a.

[0184] It should be noted that in Figure 11 , for simplicity, the input beam 1136 is illustrated as being at a normal incidence angle relative to the resonant element 1126. However, similar to the implementation of Figure 1 , the system 11 10 can be designed so that the input beam 1136 will be at a non-normal incidence angle relative to the resonant element 1126.

[0185] Figure 12 is a simplified illustration of yet another implementation of a system 1210 having features of the present invention. In the non-exclusiveimplementation of Figure 12, the system 1210 includes (i) a laser assembly 1212, (ii) a device 1216, and (iii) a system controller 1218 that are similar to the corresponding components described above and illustrated in Figure 1.

[0186] Further, the system 1210 includes an optical assembly 1214 that selectively adjusts the laser beam 1212a generated by the laser assembly 1212 to selectively provide the adjusted beam 1214a to the device 1216. In Figure 12, the optical assembly 1214 has a dual pass architecture that allows the optical assembly 1214 to have a high extinction-ratio somewhat similar to the optical assembly 514 described above and illustrated in Figure 5.

[0187] In Figure 12, the optical assembly 1214 is an acousto-optic modulator that includes (i) an assembly frame 1222; (ii) an input lens assembly 1224; (iii) an output lens assembly 1230; and (iv) a measurement assembly 1232 that are similar to the corresponding components described above and illustrated in Figure 5. However, in Figure 5, the beam makes two passes through the same resonant element 26.

[0188] In contrast, in Figure 12, the optical assembly 1214 includes a resonant element assembly 1225 having (i) a first resonant element 1226f that receives the collimated input beam 1236 and generates a first pass, element adjusted beam 1226a1 and a measurement beam 1226b when activated; (ii) a first transducer 1228af that is coupled to and drives the first resonant element 1226f; (iii) a first vibration absorber 1229f that absorbs vibration from the first resonant element 1226f; (iv) a second resonant element 1226s that receives the first pass, element adjusted beam 1226a1 and generates a second pass, element adjusted beam 1226a2 and a zeroth order beam 1226c when activated; (v) a second transducer 1228as that is coupled to the second resonant element 1226s; (vi) a second vibration absorber 1229s that absorbs vibration from the second resonant element 1226s; and (vii) a signal generator 1228b that selectively controls the transducers 1228af, 1228as. With the design of Figure 12, the beam sequentially passes through the resonant elements 1226f, 1226s of the resonant element assembly 1225 to create the two pass configuration.

[0189] In one implementation, (i) each of the resonant elements 1226f, 1226s can be similar to the resonant element 26 described above and illustrated in Figure 1 ; (ii) each transducer 1228af, 1228as can be similar to the transducer 28a described above and illustrated in Figure 1 ; and / or (iii) the signal generator 1228b can be similar to the signal generator 28b described above and illustrated in Figure 1. In oneimplementation, the signal generator 1228b directs the same signal to each transducer 1228af, 1228as. Alternatively, for example, the signal generator 1228b can independently direct a different signal to each transducer 1228af, 1228as. Still alternatively, the optical assembly 1214 can be designed to include multiple signal generators 1228b.

[0190] In the non-exclusive implementation of Figure 12, the orientation of the resonant elements 1226f, 1226s are flipped. This orientation can compensate for temperature gradients, and other effects that would otherwise change the angle of the second pass, element adjusted beam 1226a2. Alternatively, the orientation of the resonant elements 1226f, 1226s can be the same.

[0191] In Figure 12, the input beam 1236 that enters the first resonant element 1226f is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 12, the first pass, element adjusted beam 1226a1 (illustrated with long dashes) that exits the first resonant element 1226f is directed at the second resonant element 1226s, and the measurement beam 1226b is directed to the measurement assembly 1232. In this implementation, the first pass, element adjusted beam 1226a1 is the m=-1 order beam, and the measurement beam 1226b is the m=0 order beam. Alternatively, the first pass, element adjusted beam 1226a1 and / or the measurement beam 1226b can be a different order than illustrated in Figure 12.

[0192] In Figure 12, the first pass, element adjusted beam 1226a1 that enters the second resonant element 1226s during the second pass is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure 12, (i) the second pass, adjusted beam 1226a2 (illustrated with divided line) that exits the second resonant element 1226s is directed at the output lens assembly 1230. In this implementation, the second pass, adjusted beam 1226a2 is the m=-1 order beam. Alternatively, the second pass, adjusted beam 1226a2 can be a different order than illustrated in Figure 12.

[0193] Additionally and optionally, in Figure 12, the zeroth order beam 1226c exiting the second resonant element 1226s is directed a beam trap 1256 to inhibit stray light from reentering the system.

[0194] It should be noted that in Figure 12, for simplicity, the input beam 1236 is illustrated as being at a normal incidence angle relative to the resonant element 1226f. However, similar to the implementation of Figure 1 , the system 1210 can bedesigned so that the input beam 1236 will be at a non-normal incidence angle relative to the resonant element 1226f.

[0195] Figure 13 is a simplified illustration of yet another implementation of a system 1310 having features of the present invention. In the non-exclusive implementation of Figure 13, the system 1310 includes (i) a laser assembly 1312, (ii) a device 1316, and (iii) a system controller 1318 that are similar to the corresponding components described above and illustrated in Figure 1.

[0196] Further, the system 1310 includes an optical assembly 1314 that selectively adjusts the laser beam 1312a generated by the laser assembly 1312 to selectively provide the adjusted beam 1314a to the device 1316. In Figure 13, the optical assembly 1314 has a single pass architecture, and is uniquely designed so that the optical assembly 1314 has a high extinction-ratio somewhat similar to the optical assembly 514 described above and illustrated in Figure 5.

[0197] In Figure 13, the optical assembly 1314 is an acousto-optic modulator that includes (i) an assembly frame 1322; (ii) an input lens assembly 1324; (iii) an input polarization filter 1342; (iv) a resonant element 1326 that receives the collimated input beam 1336; (v) a frequency generator 1328 that selectively generates and directs a frequency through the resonant element 1326; (vi) a vibration absorber 1329; (vii) an output polarization filter 1350; (vii) an output lens assembly 1330; and (vii) a measurement assembly 1332 that are similar to the corresponding components described above and illustrated in Figure 5.

[0198] However, in Figure 13, the optical assembly 1314 includes an input polarization adjuster 1360 that adjusts the polarization of the laser beam 1312a prior to entering the resonant element 1326; and an output polarization adjuster 1362 that adjusts the polarization of the resonant adjusted beam 1326a prior to the output lens assembly 1330. Alternatively, the polarization adjusters 1360, 1362 can be located at another location of the optical assembly 1314.

[0199] The design of each polarization adjuster 1360, 1362 can be varied pursuant to the teachings provided herein. In one non-exclusive implementation, one or each polarization adjuster 1360, 1362 can be an optical prism, such as a Fresnel rhomb. Alternatively, for example, one or each polarization adjuster 1360, 1362 can be a waveplate. In this implementation, for example, the resonant element assembly is a shear mode acousto-optic modulator.

[0200] In one implementation, (i) the input fiber assembly 1320 is polarization maintaining at plus or minus forty-five degree (45°) polarization; (ii) the laser assembly 1312 is designed and oriented so that the laser beam 1312a launched from the input fiber assembly 1320 has a plus or minus forty-five degree (45°) polarization; (iii) the input polarization filter 1342 is designed to transmit light at plus or minus forty-five degrees (±45°), and reject light that is not at plus or minus forty-five degrees (±45°); (iv) the input polarization adjuster 1360 is a polarization adjuster that adjusts the polarization of the laser beam 1312a from a plus or minus 45 degrees to a circular polarization; (v) the collimated input beam 1336 entering the resonant element 1326 will have a circular polarization; (vi) the collimated, element adjusted beam 1326a exiting the resonant element 1326 will have a oppositely circular polarization; (vii) the output polarization adjuster 1362 is a minus forty-five degree (-45°) polarization adjuster that adjusts the polarization of the element adjusted beam 1326a from a circular to a minus or plus 45 degrees; (viii) the output polarization filter 1350 is designed to transmit light at minus or plus forty-five degrees (±45°), and reject light that is not at minus or plus forty-five degrees (±45°); and (ix) the output fiber assembly 1334 is polarization maintaining at minus or plus forty-five degree (45°) polarization.

[0201] In the implementation of Figure 13, the polarization maintaining fiber assemblies 1320, 1334 are aligned at plus and minus 45° instead of 0°; (ii) the polarization adjusters 1360, 1362 are ±45° (and not horizontal or vertical polarization- and not P polarization or S polarization); (iii) the Frensel rhombs 1360, 1362 are laid flat to convert +45° polarization of the collimated input beam 1336 to have a rightcircular polarization (RCP); (iv) the collimated input beam 1336 beam traverses the resonant element 1326 while collimated; (v) the element adjusted beam 1326a (m=1 order diffraction) will have a left-circular polarized (LCP); (vi) the output polarization adjuster 1362 converts LCP to -45° polarization; and (vii) the output polarization filter 1350 will remove any zeroth order scatter to provide the output adjusted beam 1314a having a high extinction ratio (e.g., >95dB) in single-pass arrangement.

[0202] It should be noted that modifications to the design of Figure 13 are possible. For example, the polarization adjusters 1360, 1362 can be swapped (+45° and -45°) as well as RCP and LCP can be swapped.

[0203] In Figure 13, the input beam 1336 that enters the resonant element 1326 is diffracted into the different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). In Figure13, (i) the resonant, adjusted beam 1326a is the m=1 order beam; and (ii) the measurement beam 1326b is the m=0 order beam.

[0204] It should be noted that when the resonant element 1326 is being activated, that other orders of diffractions are being generated, even though they are not illustrated in Figure 13. Additionally, it should be noted that the other orders of diffraction can be used as the element adjusted beam 1326a, and / or the measurement beam 1326b. For example, the optical assembly 1314 can be designed so that the m=-1 order of diffraction (m=-1 ), the m=+2 order of diffraction (m=+2), or the m=-2 order of diffraction (m=-2) beam becomes the element adjusted beam 1326a, or the measurement beam 1326b.

[0205] It should be noted that in Figure 13, the system 1310 is designed so that the input beam 1336 is at a non-normal incidence angle relative to the resonant element 1326.

[0206] Figure 14 is a simplified illustration of another implementation of a system 1410 having features of the present invention. In the non-exclusive implementation of Figure 14, the system 1410 includes (i) a laser assembly 1412, (ii) a device 1416, and (iii) a system controller 1418 that are somewhat similar to the corresponding components described above and illustrated in Figure 1.

[0207] Further, the system 1410 includes an optical assembly 1414 that selectively adjusts the laser beam 1412a generated by the laser assembly 1412 to selectively provide the output adjusted beam 1414a to the device 1416. In Figure 14, the optical assembly 1414 is somewhat similar to the optical assembly 514 described above and illustrated in Figure 5, except that the optical assembly 1414 of Figure 14 is designed to have a dual pass architecture without the use of polarization filters 542, 550, or a polarization adjuster 544a (illustrated in Figure 5). This dual pass architecture allows the optical assembly 1414 to have a high extinction-ratio as defined above. Further, because the design of Figure 14 does not utilize polarization filters 542, 550, or a polarization adjuster 544a, it may be easier and less expensive to assemble and maintain stability.

[0208] In Figure 14, the optical assembly 1414 is again an acousto-optic modulator that includes (i) an assembly frame 1422; (ii) an input lens assembly 1424; (iii) a resonant element assembly 1425 including the resonant assembly 1426 that receives the laser beam 1412a; (iv) a frequency generator 1428 that selectively generates and directs a frequency through the resonant element 1426; (v) a vibrationabsorber 1429; and (vi) an output lens assembly 1430 that are somewhat similar to the corresponding components described above and illustrated in Figure 5.

[0209] However, in Figure 14, the optical assembly 1414 does not include the input polarization filter 542, the first beam director 546, the second beam director 548, and the output polarization filter 550 of Figure 5. Further, the design of the redirector assembly 1444 is different in Figure 14. Moreover, in Figure 14, the optical assembly 1414 can optionally include a beam pointing adjustment assembly 1490.

[0210] In the implementation of Figure 14, the laser assembly 1412 generates the laser beam 1412a that is launched from the input fiber assembly 1420 at the inlet lens assembly 1424. After the laser beam 1412a is collimated by the inlet lens assembly 1424, it is directed at the resonant element 1426.

[0211] When the frequency generator 1428 directs a frequency through the resonant element 1426, the optical assembly 1414 is activated and is in the “ON Position”. In contrast, when the frequency generator 1428 is not directing a frequency through the resonant element 1426, the optical assembly 1414 is deactivated and is in the “OFF Position”.

[0212] As provided above, the optical assembly 1414 of Figure 14 is designed to have a dual pass architecture. In this implementation, the beam makes two, collimated passes through the resonant element 1426 to improve the extinction-ratio of the optical assembly 1414.

[0213] In the first pass through the resonant element 1426, when activated, the collimated input beam 1436 is scattered into a diffraction pattern having different orders of diffraction (m=... , -2, -1 , 0, +1 , +2, ...). Figure 14 illustrates when the resonant element 1426 is activated, the first pass, element adjusted beam 1426a1 (illustrated with a long dashed line), and an extra beam 1426b exiting the resonant element 1426 during the first pass. In this example, the first pass, m=-1 order of diffraction is the first pass, element adjusted beam 1426a1 , and a first pass, m=0 order of diffraction is the extra beam 1426b. The first pass, m=-1 order of diffraction 1426a1 can alternatively be referred to as the “first pass, first order beam” or the “first pass, adjusted beam”; and the first pass, m=0 order of diffraction 1426b can be referred to as the “first pass, zeroth order beam”.

[0214] Alternatively, for example, the optical assembly 1414 can be designed so that the m=+1 order of diffraction (m=+1), the m=+2 order of diffraction (m=+2), orthe m=-2 order of diffraction (m=-2) beam becomes the first pass, element adjusted beam 1426a1 , or the extra beam 1426b.

[0215] In Figure 14, when not activated, the resonant element 1426 functions as a window with the collimated input beam 1436 mainly being transmitted directly through the resonant element 1426, with some slight scattering.

[0216] In the non-exclusive implementation of Figure 14, when activated, the majority of the laser beam 1412a is scattered as the first pass, m=-1 order of diffraction 1426a1 that is directed at the redirector assembly 1444. In one design, the redirector assembly 1444 (i) receives the first pass, adjusted beam 1426a1 ; and (ii) redirects a redirected beam 1426ar (illustrated with dot dashed line) back into the resonant element 1426 for a second pass through the resonant element 1426 offset from the first pass.

[0217] A number of alternative, non-exclusive designs of the redirector assembly 1444 are possible. As a non-exclusive example, the redirector assembly 1444 can form a cat’s eye lens, or another type of redirector. In the implementation of Figure 14, the redirector assembly 1444 includes a redirector lens assembly 1444b, and a redirector 1444c that form the cat’s eye lens. The design of each of these components can be varied pursuant to the teachings provided herein and to achieve the desired spaci ng / offset (e.g., along the X axis) between the passes through the resonant element 1426. Alternatively, the redirector assembly 1444 can be designed to include more or fewer components.

[0218] In Figure 14, the redirector lens assembly 1444b focuses the light on the redirector 1444c. Next, the light that reflects off of the redirector 1444c, is collimated by the redirector lens assembly 1444b, and directed at the resonant element 1426 for the second pass through the resonant element 1426.

[0219] The redirector lens assembly 1444b (i) focuses the first pass, adjusted beam 1426a1 at the redirector 1444c, (ii) collimates the beam reflected by the redirector 1444c, and (iii) directs that collimated redirected beam 1426ar at the resonant element 1426. The redirector lens assembly 1444b is operational in the wavelength(s) of the laser beam.

[0220] The redirector 1444c can be a mirror or another type of reflective element.

[0221] Subsequently, the redirected beam 1426ar that enters the resonant element 1426 during the second pass is diffracted into the different orders of diffraction(m=... , -2, -1 , 0, +1 , +2, ...). In Figure 14, (i) a second pass, element adjusted beam 1426a2 (illustrated with divided line) that exits the resonant element 1426 is directed at the beam pointing assembly 1490. In this implementation, the second pass, element adjusted beam 1426a2 is the second pass, m=-1 order of diffraction 1426a2. This beam can alternatively be referred to as the “second pass, first order beam” or the “second pass, adjusted beam”. Alternatively, for example, the optical assembly 1414 can be designed so that the m=+1 order of diffraction (m=+1), the m=+2 order of diffraction (m=+2), or the m=-2 order of diffraction (m=-2) beam becomes the second pass, element adjusted beam 1426a2.

[0222] Further, in the “OFF” position, a small amount of input beam 1436 can be scattered from the resonant element 1426 to redirector assembly 1444, and returned to the resonant element 1426 as a low intensity, redirected beam. However, because the resonant element 1426 is “OFF”, the majority of this low intensity, redirected beam will be transmitted through as the zeroth order beam and miss the beam pointing assembly 1490. In this design, only a small amount of the low intensity redirected beam will scattered back to the beam pointing assembly 1490. As a result thereof, in the “OFF” position, very few, if any photons will reach the device 1416.

[0223] It should be noted that in the implementation of Figure 14, the extra beam 1426b is directed to a beam trap 1440 that absorbs and / or diffuses the extra beam 1426b to inhibit stray light from reentering the system. The other systems described above can utilize the beam trap 1440 instead of the measurement system 532 (illustrated in Figure 5)

[0224] Alternatively, the optical assembly 1414 of Figure 14 can optionally also include a measurement assembly 532 (illustrated in Figure 5) that is integrated into the optical assembly 1414 similar to the design of Figure 5.

[0225] The beam pointing adjustment assembly 1490 is controlled and / or adjusted to precisely adjust the pointing of the output adjusted beam 1414a onto the output fiber assembly 1434. As a result thereof, the output adjusted beam 1414a will be accurately centered, focused, and coupled to the output fiber assembly 1434.

[0226] As provided herein, during operation of the system 1410, temperature cycles, stress relief, and / or vibration can cause one or more of the components to move slightly, and adversely influence the pointing of the output adjusted beam 1414a onto the output fiber assembly 1434. In certain designs, the system 1410 can be temperature cycled and / or vibrated to get the components to settle in position for finalalignment. Subsequently, the beam pointing adjustment assembly 1490 can be used to adjust and correct the pointing of the output adjusted beam 1414a to maximize the output adjusted beam 1414a received by the output fiber assembly 1434.

[0227] Alternatively, for example, the output adjusted beam 1414a can be directed at the output fiber assembly 1434 without the beam pointing adjustment assembly 1490.

[0228] A number of different designs of the beam pointing adjustment assembly 1490 can be utilized. In one non-exclusive implementation, the beam pointing adjustment assembly 1490 includes (i) a first pointing adjuster 1490a (e.g., a first wedged window), and (ii) a second pointing adjuster 1490b (e.g., a second wedged window). In this design, the pointing adjusters 1490a, 1490b are arranged in series and spaced apart so that the light travels through the first pointing adjuster 1490a to the second pointing adjuster 1490b. In certain designs, one or both pointing adjusters 1490a, 1490b can be individually and selectively moved to adjust the pointing of the output adjusted beam 1414a. With this design, for example, after the system 1410 is ready for final alignment, the pointing adjusters 1490a, 1490b can be individually moved and adjusted until a measured output power in the optical fiber assembly 1434 is maximized. Generally, maximum output power is achieved when the output adjusted beam 1414a is properly focused on the optical fiber assembly 1434. When the maximum is achieved, the pointing adjusters 1490a, 1490b can be fixedly secured to the assembly frame 1422.

[0229] For example, the pointing adjusters 1490a, 1490b can be a Risley pair that can be moved until that output adjusted beam 1414a is properly focused. These Risley pairs are relatively insensitive to subsequent movement. In an alternative design, the beam pointing adjustment assembly 1490 can include only one, or more than two pointing adjusters.

[0230] It should be noted that in Figure 14, the input beam 1436 is at a nonnormal incidence angle relative to the resonant element 1426. As provided herein, an effective diffraction grating is created when the frequency generator 1428 vibrates the resonant element 1426. This effective diffraction grating will have an acceptance angle that refers to the range of angles of the input beam 1436 that will be efficiently diffracted by the grating. The acceptance angle will depend upon the RF signal frequency from the frequency generator 1428, the material of the resonant element 1426, and the wavelength of input beam 1436.

[0231] In Figure 14, the laser beam 1412a enters the resonant element 1426 at an input angle la relative to normal, and the second pass, element adjusted beam 1426a2 exits the resonant element 1426 at an output angle Oa relative to normal. In one non-exclusive implementation, the input angle la, and / or the output angle Oa is between 0.5 degrees and one degree. However, in other implementations, the input angle la, and / or the output angle Oa can be approximately 0.5, 1 , 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more degrees.

[0232] It should also be noted that the incidence angle of the input beam 1436 relative to normal on the resonant element 1426 can be selected to achieve the desired exit angle of the element adjusted beam1426a2 and / or performance of the system 1410.

[0233] Optionally, as illustrated in Figure 14, the redirector assembly 1444 can be uniquely designed to be telecentric. With this design, changes to the RF frequency do not change the fiber coupling to the output fiber assembly 1434. Stated differently, the optical power out of output fiber assembly 1434 is insensitive to the choice of RF frequency. As a result, the frequency of output adjusted beam 1414a can be controlled independently of the power of output adjusted beam 1414a.

[0234] More specifically, in Figure 14, the redirector lens assembly 1444b and the redirector 1444c are designed and positioned so that the redirector lens assembly 1444b is telecentric with the lens distance 1492 being approximately equal to the focal length 1494. As used herein, approximately equal shall mean within, for example, approximately 10, 1 , or 0.1 percent. Because of the symmetry between the lens distance 1492 and the focal length 1494, the system 1410 is insensitive to changes in the RF frequency. As a result, the frequency of output adjusted beam 1414a can be controlled independently of the power of output adjusted beam 1414a.

[0235] It should be noted that the other systems described above, such as illustrated in Figure 5, 8, and 11 can be modified to have a telecentric design.

[0236] Figure 15 is a simplified side view of the resonant element assembly 1525 including a resonant element 1526, a transducer 1528a, a signal generator 1528b that drives the transducer 1528a, and an element mounting assembly 1570 that retains the resonant element 1526 with improved thermal management and vibrational management of the resonant element 1526. It should be noted that the resonant element assembly 1525 can be incorporated in any of the implementations provided herein.

[0237] As provided herein, as the RF signal from the signal generator 1528b is varied to the transducer 1528a, and the amount of heat generated in the resonant element 1526 varies. This results in variable heating of the resonant element 1526. Variable heating of the resonant element 1526 can lead to thermal gradients in the resonant element 1526 that distort the resonant element 1526.

[0238] As an overview, the element mounting assembly 1570 and resonant element 1526 are uniquely designed to quickly and efficiently dissipate heat from the resonant element 1526 in a symmetrical fashion. This will minimize / reduce any thermal gradients across the resonant element 1526, and this will minimize / reduce any distortion of the resonant element 1526. As provided herein, distortion (rotation and / or bending) of the resonant element 1526 can (i) change the pitch angle (pointing) of the element adjusted beam 26a (illustrated in Figure 1 ) that exits the resonant element 1526; and / or degrade the diffraction efficiency of the resonant element 1526.

[0239] The design of the element mounting assembly 1570 can be varied pursuant to the teachings provided herein to suit the design of the resonant element 1526. In the non-exclusive implementation of Figure 15, the resonant element 1526 is somewhat rectangular shaped and includes (i) a transducer side 1572a that engages and is coupled to the transducer 1528a; (ii) a reflector side 1572b that reflects the energy, the reflector side 1572b being opposite to and spaced apart from the transducer side 1572a; (iii) a first mounting side 1572c that engages and is coupled to the element mounting assembly 1570; (iv) a second mounting side 1572d that engages and is coupled to the element mounting assembly 1570, the second mounting side 1572d being opposite to and spaced apart from the first mounting side 1572c; (v) an inlet side (not shown in Figure 15) that receives the collimated inlet beam 36 (illustrated in Figure 1); and (vi) and outlet side 1572e that is opposite to and spaced apart from the inlet side, wherein the element adjusted beam 26a (illustrated in Figure 1 ) exits from the outlet side 1572e. In this design, the transducer side 1572a and reflector side 1572b are transverse to the other sides 1572c-1572e. Additionally, an element longitudinal axis 1572f of the resonant element 1526 is also represented in Figure 15.

[0240] Further, in the non-exclusive implementation of Figure 15, the element mounting assembly 1570 includes (i) a mounting frame 1574; (ii) a first coupler 1576 that couples the first mounting side 1572c of the transducer element 1526 to the mounting frame 1574; and (iii) a second coupler 1578 that couples the secondmounting side 1572d of the transducer element 1526 to the mounting frame 1574. As a result thereof, the resonant element 1526 is retained on both mounting sides 1572c, 1572d in a symmetrical fashion. As a result thereof, heat can be removed from the resonant element 1526 in a symmetrical fashion with the element mounting assembly 1570. The design of these components can be varied.

[0241] In Figure 15, the mounting frame 1574 is a generally rectangular “U” shaped, rigid bracket that includes a first frame side 1574a, an opposed second frame side 1574b that is spaced apart from the first frame side 1574a, and a connector frame region 1574c that connects the frame sides 1574a, 1574b together. In one implementation, the frame sides 1574a, 1574b extend and cantilever away from the connector frame region 1574c, and the frame sides 1574a, 1574b are substantially parallel to each other.

[0242] In one implementation, the mounting frame 1574 is thermally conductive, and made of a material having a coefficient of thermal expansion that is approximately equal to the coefficient of thermal expansion of the resonant element 1526. As used herein “approximately equal” with regards to the coefficient of thermal expansion shall meant within at least three parts per million per Kelvin. With this design, the mounting frame 1574 and the resonant element 1526 will expand at approximately the same rate to reduce the likelihood of distortion of the resonant element 1526.

[0243] The first coupler 1576 couples and attaches the first mounting side 1572c of the transducer element 1526 to the first frame side 1574a of the mounting frame 1574. Similarly, the second coupler 1578 couples and attaches the second mounting side 1572d of the transducer element 1526 to the second frame side 1574b of the mounting frame 1574. In one, non-exclusive implementation, one or both of the couplers 1576, 1578 are thermally conductive, and can be made of a material having a coefficient of thermal expansion that is approximately equal to the coefficient of thermal expansion of the resonant element 1526 and / or the mounting frame 1574. With this design, the couplers 1576, 1578, the mounting frame 1574 and the resonant element 1526 will expand at approximately the same rate to reduce the likelihood of distortion of the resonant element 1526.

[0244] In one implementation, the mounting side 1572c, 1572d of the resonant element 1526 has a “fine ground” surface texture, and a thin layer of indium is positioned thereon to increase the rate of heat transfer from the resonant element 1526 to the mounting frame 1574 via the couplers 1576, 1578.

[0245] With the design of Figure 15, the heat generated in the resonant element 1526 is symmetrically transferred to the frame sides 1574a, 1574b, in contrast to being transferred to only one side. This will minimize any thermal gradient in the resonant element and minimize deformation of the resonant element 1526.

[0246] Additionally, in the implementation of Figure 15, the reflector side 1572b of the transducer element 1526 is uniquely designed to direct the reflected energy 1579 (illustrated with dashed arrows) symmetrically at the mounting sides 1572c, 1572d. As provided herein, when the transducer 1528a is activated, it creates an acoustic beam 1580 (illustrated as an arrow) moving in the resonant element 1526 from the transducer side 1572a towards the reflector side 1572b. When the acoustic beam 1580 engages the reflector side 1572b, and the reflector side 1572b symmetrically redirects the reflected energy 1579 at the mounting sides 1572c, 1572d, where it can be symmetrically absorbed by the couplers 1576, 1578. The reflected energy 1579 absorbed by the couplers 1576, 1578 generates heat. However, with the present design, the heat generated will be symmetrical, thereby minimizing any thermal gradient in the resonant element and minimizing deformation of the resonant element 1526.

[0247] As provided herein, reflections 1579 back to the transducer side 1572a in the resonant element 1526 create heat in at the transducer side 1572a that can lead to thermal gradients and distortion of the resonant element 1526. Further, the thermal gradients can alter the shape of the grating formed in the resonant element 1526, thereby adversely influencing the performance of the resonant element 1526.

[0248] In one implementation, the reflector side 1572b of the resonant element 1526 is polished (instead of fine-ground). This avoids heating at the reflector side 1572b that would lead to a horizontal thermal gradient across the resonant element 1526.

[0249] Further, in one implementation, the reflector side 1572b of the resonant element 1526 is cut at angles to deflect the incoming acoustic beam 1580 moving from the transducer side 1572a towards the reflector side 1572b in the resonant element 1526. In one implementation, the reflector side 1572b is concave shaped as illustrated in Figure 15. In this implementation, the reflector side 1572b has a concave shape. In this design, the reflector side 1572b is at a non-normal angle relative to the longitudinal axis 1572f.

[0250] Stated in another fashion, the reflector side 1572b of the resonant element 1526 is at a non-normal angle relative to at least one of the longitudinal axis 1572f, inlet side, the outlet side 1572e, the first frame side 1574a, and the second frame side 1574b.

[0251] With this design, the reflected energy 1579 is directed at an angle towards the transducer side 1572a and the mounting sides 1572c, 1572d instead of directly back at the transducer side 1572a.

[0252] Figure 16 is a simplified side view of the resonant element assembly 1625 including a resonant element 1626, a transducer 1628a, a signal generator 1628b that drives the transducer 1628a, and an element mounting assembly 1670 that retains the resonant element 1626 with improved thermal management and vibrational management of the resonant element 1626. It should be noted that the resonant element assembly 1625 can be incorporated in any of the implementations provided herein.

[0253] In Figure 16, the transducer 1628a, the signal generator 1628b, and the element mounting assembly 1670 are similar to the corresponding components described above and illustrated in Figure 15. However, in Figure 16, the resonant element 1626 is slightly different.

[0254] In Figure 16, the resonant element 1626 is again designed to reduce reflected energy 1679 (illustrated with dashed arrows) from the acoustic beam 1680 from being directed back at the transducer side 1672a.

[0255] In Figure 16, the reflector side 1672b of the resonant element 1626 is cut at angles to deflect the incoming acoustic beam 1680 moving from the transducer side 1672a towards the reflector side 1672b in the resonant element 1626. In this implementation, the reflector side 1672b is convex.

[0256] Stated in another fashion, the reflector side 1672b of the resonant element 1626 is at a non-normal angle relative to at least one of the longitudinal axis 1672f, inlet side, the outlet side 1672e, the first frame side 1674a, and the second frame side 1674b. In this design, the reflector side 1672b is at a non-normal angle relative to the longitudinal axis 1672f.

[0257] With this design, the reflected energy 1679 is directed at an angle towards the transducer side 1672a and the mounting sides 1672c, 1672d instead of directly back at the transducer side 1672a.

[0258] Figure 17 is a perspective view of a first implementation of a beam trap 1740 that receives unwanted light, and absorbs and / or diffuses the light to inhibit stray light from reentering the system. It should be noted that the beam trap 1740 can include a top that is not shown so that the other features of the beam trap 1740 are visible. The beam trap 1740 can be used in any of the implementations described above or in another type of system. In the non-exclusive implementation of Figure 17, the beam trap 1740 includes a trap housing 1740a that forms a spiral channel (passageway) 1740b that receives the unwanted light and repeatedly scatters the unwanted light to form a high-capture beam dump. In one design, the trap housing 1740a is generally disk shaped, that the channel 1740b has a generally rectangular shaped cross-section. However, other cross-sectional shapes are possible. In certain designs, the cross-section shape is larger than the cross-section shape of the beam.

[0259] In the design of Figure 17, the beam trap 1740 has substantially no surfaces at normal incidence. In this design, the entering beam will repeatedly scatter from and be absorbed by the rectangular channel 1740b, ensuring ultra-low levels of returned light. As provided herein, the channel 1740b can have a curved, (e.g., circular) shape, and / or form one or more loops of a spiral. The circular shape can be at least three quarters of the circle, a full circle, more than a full circle, or multiple circles. The length of the channel 1740b can be optimized for the desired beam capture performance. In the non-exclusive implementation of Figure 17, the channel 1740b forms a single loop.

[0260] It should be noted that the beam trap 1740 can alternatively be referred to as a light trap or light absorber that captures stray and / or unwanted reflected light, and inhibit this light from entering into and disrupting the system. The beam trap 1740has a high extinction ratio that inhibits undiffracted beams and ghost reflections in the system 10 (illustrated in Figure 1).

[0261] Figure 18 is a perspective view of another implementation of a beam trap 1840 that receives unwanted light, and absorbs and / or diffuses the light to inhibit stray light from reentering the system. It should be noted that the beam trap 1840 can include a top that is not shown so that the other features of the beam trap 1840 are visible. The beam trap 1840 can be used in any of the implementations described above or in another type of system. In the non-exclusive implementation of Figure 18, the beam trap 1840 includes a trap housing 1840a that forms a spiral channel (passageway) 1840b similar to the design illustrated in Figure 17. However, in theimplementation of Figure 18, the spiral channel 1840b is longer. In the non-exclusive implementation of Figure 18, the channel 1840b forms multiple (e.g., two) loops. This will provide better beam capture.

[0262] Figure 19 is a simplified illustration of another implementation of resonant element 1926 and a transducer 1928a that can be used in any of the implementations described above. Figure 19 also illustrates the effective diffraction grating 1938 (dashed lines).

[0263] In the implementation of Figure 19, the incoming laser beam 1936 is not collimated, and the element adjusted beam 1926a (illustrated with long dashes) that exits the resonant element 1926 when the resonant element 1926 is activated is also not collimated. Instead, the system of Figure 19 is designed so that the incoming laser beam 1936 is focused through the resonant element 1926. In the implementation of Figure 19, the incoming laser beam 1936 can focused at any location in the resonant element 1926. As a non-exclusive example, the incoming laser beam 1936 can focused at the center of the resonant element 1926.

[0264] As provided herein, having a variable beam size inside the resonant element 1926 enables tradeoffs regarding beam power, switching speed, and frequency tuning speed. Thus, the system can be tailored to optimize these properties.

[0265] Figure 20 is a simplified illustration of another implementation of a system 2010 having features of the present invention. In the non-exclusive implementation of Figure 20, the system 2010 includes (i) a laser assembly 2012, (ii) a device 2016, and (iii) a system controller 2018 that are somewhat similar to the corresponding components described above and illustrated in Figure 1.

[0266] Further, the system 2010 includes an optical assembly 2014 that selectively adjusts the laser beam 2012a generated by the laser assembly 2012 to selectively provide the output adjusted beam 2014a to the device 2016. In Figure 20, the optical assembly 2014 is somewhat similar to the optical assembly 1414 described above and illustrated in Figure 14, except that the optical assembly 2014 of Figure 20 is designed to also include polarization filters 2042, 2050, and a polarization adjuster 2044a that are similar to the design in Figures 5 and 8. This dual pass architecture that includes the polarization filters 2042, 2050 allows the optical assembly 2014 to have a high extinction-ratio as defined above.

[0267] In Figure 20, the optical assembly 2014 is again an acousto-optic modulator that includes (i) an assembly frame 2022; (ii) an input lens assembly 2024;(iii) a resonant element assembly 2025 that receives the laser beam 2012a; (iv) a frequency generator 2028; (v) an output lens assembly 2030; and (vi) a redirector assembly 2044 that are similarto the corresponding components described above and illustrated in Figure 14.

[0268] In the implementation of Figure 20, the laser assembly 2012 generates the laser beam 2012a that is launched from the input fiber assembly 2020 at the inlet lens assembly 2024. In this design, the laser assembly 2012 is designed so that the laser beam 2012a has the first polarization and the input polarization filter 2042 is designed to transmit light having the first polarization and block light that is not at the first polarization. With this design, the laser beam 2012a is transmitted through the input polarization filter 2042.

[0269] In one implementation, when the resonant element assembly 2025 is activated, the polarization adjuster 2044a receives the first pass, element adjusted beam 2026a1 , and directs that beam 2026a1 at the redirector assembly 2044. Subsequently, the polarization adjuster 1244a directs the rotated, redirected beam 2026ar at the resonant element assembly 2025 for the second pass. At this time, the redirected beam 2026ar has a second polarization and is directed back into the resonant element assembly 2025 for the second pass slightly offset (e.g., along the X axis) from the first pass.

[0270] In this implementation, when the resonant element assembly 2025 is activated, the second pass, element adjusted beam 2026a2 will be at the second polarization directed at the beam pointing adjuster assembly 2090 and the second polarization filter 2050 that transmits light at the second polarization.

[0271] In Figure 20, when not activated, the resonant element assembly 2025 functions as a window with the light mainly being transmitted directly through the resonant element assembly 2025, with some slight scattering.

[0272] It should be noted that in the implementation of Figure 20, the extra beam 2026b is directed to a beam trap 2040 that absorbs and / or diffuses the extra beam 2026b to inhibit stray light from reentering the system. Alternatively, the optical assembly 2014 of Figure 20 can optionally also include a measurement assembly 532 (illustrated in Figure 5) that is integrated into the optical assembly 2014 similar to the design of Figure 5.

[0273] It should be noted that any of the systems 10, 310, 510, 610, 710, 810, 910, 1010, 1110, 1210, 1310, 1410, 2010 described above can be modified so thatthe incoming laser beam is not collimated, and can be focused through the resonant element. It should be also be noted that any of the systems 10, 310, 510, 610, 710, 810, 910, 1010, 1110, 1210, 1310, 1410, 2010 can be modified to include one or more features from the other systems.

[0274] While the particular designs as shown and disclosed herein is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.

Claims

What is claimed is:

1. An optical assembly that receives an input beam and selectively provides an adjusted beam, the optical assembly comprising: a resonant element assembly that receives the input beam, the resonant element assembly including a first resonant element; and a frequency generator that selectively directs a frequency through the resonant element assembly to selectively provide the adjusted beam that exits the resonant element assembly, wherein the frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly.

2. The optical assembly of claim 1 wherein the input beam is collimated.

3. The optical assembly of claim 1 further comprising an input lens assembly that collimates the input beam to create a collimated input beam that is directed at the first resonant element.

4. The optical assembly of claim 1 having an extinction-ratio of at least eighty decibels.

5. The optical assembly of claim 1 wherein the adjusted beam exiting the resonant element assembly is collimated.

6. The optical assembly of claim 1 wherein the beam makes at least two passes through the first resonant element to form the adjusted beam.

7. The optical assembly of any one of claims 1-6 wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width is at least forty percent of the element width.

8. The optical assembly of any one of claims 1-6 wherein the first transducer has a transducer width, and the first resonant element has an elementwidth, and wherein the transducer width and the element width are selected so that the first resonant element has a narrow angle tolerance when vibrated.

9. The optical assembly of any one of claims 1-6 wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width and the element width are selected so that the first resonant element forms a grating when vibrated that diverges slowly.

10. The optical assembly of any one of claims 1-6 having an extinction-ratio of at least ninety decibels.11 . The optical assembly of any one of claims 1-6 having an extinction-ratio of at least ninety-five decibels.

12. The optical assembly of any one of claims 1-6 wherein the input beam exits the first resonant element as a first pass, element adjusted beam, and wherein the optical assembly includes a redirector assembly which redirects the first pass, adjusted beam back into the first resonant element, and wherein a second pass, adjusted beam exits the first resonant element.

13. The optical assembly of claim 12 wherein the input beam has a first polarization, and the redirector assembly includes a polarization adjuster that adjusts the polarization of the first pass, adjusted beam to be a second polarization prior to being redirected back into the first resonant element to create the second pass, adjusted beam.

14. The optical assembly of claim 13 further comprising an output polarization filter that receives the second pass, adjusted beam, wherein the output polarization filter transmits light at the second polarization and blocks light at the first polarization.

15. The optical assembly of claim 14 further comprising an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the first polarization and blocks light at the second polarization.

16. The optical assembly of claim 12 wherein the redirector assembly includes a redirector lens assembly and a redirector, and wherein the redirector lens assembly is telecentric.

17. The optical assembly of any one of claims 1-5 wherein the input beam exits the first resonant element as a first pass, adjusted beam, and wherein the resonant element assembly includes a second resonant element that receives the first pass, adjusted beam to create a second pass adjusted beam when the second resonant element is vibrated.

18. The optical assembly of claim 17 wherein the orientation of the second resonant element is inverted from the orientation of the first resonant element.

19. The optical assembly of any one of claims 1-6 further comprising an output polarization adjuster that adjusts the polarization of the adjusted beam that exits the first resonant element to be an output polarization.

20. The optical assembly of claim 19 further comprising an output polarization filter that receives the beam that exits the output polarization adjuster, wherein the output polarization filter transmits light at the output polarization and blocks other polarizations.21 . The optical assembly of any one of claims 1-6 further comprising an input polarization adjuster that adjusts the polarization of the input beam that enters the resonant element assembly.

22. The optical assembly of claim 21 wherein the input beam has an input polarization, and further comprising an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the input polarization and blocks other polarizations.

23. The optical assembly of any one of claims 1-6 further comprising an output fiber assembly that receives the adjusted beam, wherein the output fiberassembly includes an optical fiber having a fiber inlet facet that receives the adjusted beam, and a fiber cap that covers the inlet facet.

24. The optical assembly of any one of claims 1-6 further comprising an input fiber assembly that launches the laser beam, wherein the input fiber assembly includes an optical fiber having a fiber outlet facet that launches the laser beam, and a fiber cap that covers the fiber outlet facet.

25. The optical assembly of any one of claims 1-6 further comprising an integrated measurement system that receives a measurement beam that exits the resonant element assembly.

26. The optical assembly of claim 25 wherein the measurement system includes a frequency discriminator that compares two different order beams that exit the first resonant element.

27. The optical assembly of claim 25 wherein the measurement system determines a first characteristic of the measurement beam.

28. The optical assembly of claim 27 wherein the first characteristic is selected from the group including power, frequency, and polarization of the measurement beam.

29. The optical assembly of any one of claims 1-6 wherein the resonant element assembly further comprises an element mounting assembly that retains the first resonant element in a symmetrical fashion.

30. The optical assembly of any one of claims 1-6 wherein the resonant element assembly includes a reflector side that reflects vibration energy in a symmetrical fashion.31 . The optical assembly of any one of claims 1-6 further comprising a beam trap that receives unwanted light, wherein the beam trap is designed to repeatedly scatter the received unwanted light in a spiral channel.

32. The optical assembly of claim 1 wherein the input beam is focused through the resonant element assembly.

33. An optical assembly that receives an input beam and selectively provides an adjusted beam, the optical assembly comprising: a resonant element assembly that receives the input beam, the resonant element assembly including a first resonant element; and a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly, wherein the frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly; wherein the adjusted beam that exits the resonant element assembly is collimated; and wherein the optical assembly has an extinction-ratio of at least eighty decibels.

34. The optical assembly of claim 33 wherein the input beam is collimated.

35. The optical assembly of claim 33 further comprising an input lens assembly that collimates the input beam to create a collimated input beam that is directed at the first resonant element.

36. The optical assembly of claim 33 wherein the beam makes at least two passes through the first resonant element to form the adjusted beam.

37. The optical assembly of claim 33 wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width is at least forty percent of the element width.

38. The optical assembly of claim 33 having an extinction-ratio of at least ninety decibels.

39. The optical assembly of claim 33 wherein the input beam exits the first resonant element as a first pass, element adjusted beam, and wherein the optical assembly includes a redirector assembly which redirects the first pass, adjusted beam back into the first resonant element, and wherein a second pass, adjusted beam exits the first resonant element.

40. The optical assembly of claim 39 wherein the input beam has a first polarization, and the redirector assembly includes a polarization adjuster that adjusts the polarization of the first pass, adjusted beam to be a second polarization prior to being redirected back into the first resonant element to create the second pass, adjusted beam.

41. The optical assembly of claim 40 further comprising an output polarization filter that receives the second pass, adjusted beam, wherein the output polarization filter transmits light at the second polarization and blocks light at the first polarization.

42. The optical assembly of claim 41 further comprising an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the first polarization and blocks light at the second polarization.

43. The optical assembly of claim 33 wherein the input beam exits the first resonant element as a first pass, adjusted beam, and wherein the resonant element assembly includes a second resonant element that receives the first pass, adjusted beam to create a second pass adjusted beam when the second resonant element is vibrated.

44. The optical assembly of claim 43 wherein the orientation of the second resonant element is inverted from the orientation of the first resonant element.

45. The optical assembly of claim 33 further comprising an output polarization adjuster that adjusts the polarization of the adjusted beam that exits the first resonant element to be an output polarization.

46. The optical assembly of claim 45 further comprising an output polarization filter that receives the beam that exits the output polarization adjuster, wherein the output polarization filter transmits light at the output polarization and blocks other polarizations.

47. The optical assembly of claim 33 further comprising an input polarization adjuster that adjusts the polarization of the input beam that enters the resonant element assembly.

48. The optical assembly of claim 47 wherein the input beam has an input polarization, and further comprising an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the input polarization and blocks other polarizations.

49. The optical assembly of claim 33 further comprising an output fiber assembly that receives the adjusted beam, wherein the output fiber assembly includes an optical fiber having a fiber inlet facet that receives the adjusted beam, and a fiber cap that covers the inlet facet.

50. The optical assembly of claim 33 further comprising an input fiber assembly that launches the laser beam, wherein the input fiber assembly includes an optical fiber having a fiber outlet facet that launches the laser beam, and a fiber cap that covers the fiber outlet facet.

51. The optical assembly of claim 33 further comprising an integrated measurement system that receives a measurement beam that exits the resonant element assembly.

52. The optical assembly of claim 33 wherein the resonant element assembly further comprises an element mounting assembly that retains the first resonant element in a symmetrical fashion.

53. The optical assembly of claim 33 wherein the resonant element assembly includes a reflector side that reflects vibration energy in a symmetrical fashion.

54. The optical assembly of claim 33 further comprising a beam trap that receives unwanted light, wherein the beam trap is designed to repeatedly scatter the received unwanted light in a spiral channel.

55. An optical assembly that receives an input beam and selectively provides an adjusted beam, the optical assembly comprising: a resonant element assembly that receives the input beam, the resonant element assembly including a first resonant element; and a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly, wherein the frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly; wherein the beam makes at least two passes through the resonant element assembly to form the adjusted beam; and wherein the adjusted beam that exits the resonant element assembly is collimated.

56. The optical assembly of claim 55 wherein the input beam is collimated.

57. The optical assembly of claim 55 further comprising an input lens assembly that collimates the input beam to create a collimated input beam that is directed at the first resonant element.

58. The optical assembly of claim 55 wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width is at least forty percent of the element width.

59. The optical assembly of claim 55 having an extinction-ratio of at least eighty decibels.

60. The optical assembly of claim 55 wherein the input beam exits the first resonant element as a first pass, element adjusted beam, and wherein the optical assembly includes a redirector assembly which redirects the first pass, adjusted beam back into the first resonant element, and wherein a second pass, adjusted beam exits the first resonant element.

61. The optical assembly of claim 60 wherein the input beam has a first polarization, and the redirector assembly includes a polarization adjuster that adjusts the polarization of the first pass, adjusted beam to be a second polarization prior to being redirected back into the first resonant element to create the second pass, adjusted beam.

62. The optical assembly of claim 61 further comprising an output polarization filter that receives the second pass, adjusted beam, wherein the output polarization filter transmits light at the second polarization and blocks light at the first polarization.

63. The optical assembly of claim 62 further comprising an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the first polarization and blocks light at the second polarization.

64. The optical assembly of claim 55 wherein the input beam exits the first resonant element as a first pass, adjusted beam, and wherein the resonant element assembly includes a second resonant element that receives the first pass, adjusted beam to create a second pass adjusted beam when the second resonant element is vibrated.

65. The optical assembly of claim 64 wherein the orientation of the second resonant element is inverted from the orientation of the first resonant element.

66. The optical assembly of claim 55 further comprising an output polarization adjuster that adjusts the polarization of the adjusted beam that exits the first resonant element to be an output polarization.

67. The optical assembly of claim 66 further comprising an output polarization filter that receives the beam that exits the output polarization adjuster, wherein the output polarization filter transmits light at the output polarization and blocks other polarizations.

68. The optical assembly of claim 55 further comprising an input polarization adjuster that adjusts the polarization of the input beam that enters the resonant element assembly.

69. The optical assembly of claim 68 wherein the input beam has an input polarization, and further comprising an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the input polarization and blocks other polarizations.

70. The optical assembly of claim 55 further comprising an output fiber assembly that receives the adjusted beam, wherein the output fiber assembly includes an optical fiber having a fiber inlet facet that receives the adjusted beam, and a fiber cap that covers the inlet facet.

71. The optical assembly of claim 55 further comprising an input fiber assembly that launches the laser beam, wherein the input fiber assembly includes an optical fiber having a fiber outlet facet that launches the laser beam, and a fiber cap that covers the fiber outlet facet.

72. The optical assembly of claim 55 further comprising an integrated measurement system that receives a measurement beam that exits the resonant element assembly.

73. The optical assembly of claim 55 wherein the resonant element assembly further comprises an element mounting assembly that retains the first resonant element in a symmetrical fashion.

74. The optical assembly of claim 55 wherein the resonant element assembly includes a reflector side that reflects vibration energy in a symmetrical fashion.

75. The optical assembly of claim 55 further comprising a beam trap that receives unwanted light, wherein the beam trap is designed to repeatedly scatter the received unwanted light in a spiral channel.

76. An optical assembly that receives an input beam having an input polarization, and selectively provides an adjusted beam having a second polarization, the optical assembly comprising: a resonant element assembly that receives the input beam, the resonant element assembly including a first resonant element; a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly, wherein the frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly; and an output polarization adjuster that adjusts the polarization of an element adjusted beam that exits the resonant element assembly to be the second polarization.

77. The optical assembly of claim 76 wherein the input beam is collimated.

78. The optical assembly of claim 76 further comprising an input lens assembly that collimates the input beam to create a collimated input beam that is directed at the first resonant element.

79. The optical assembly of claim 76 wherein the beam makes at least two passes through the first resonant element to form the adjusted beam.

80. The optical assembly of claim 76 wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width is at least forty percent of the element width.

81. The optical assembly of claim 76 having an extinction-ratio of at least eighty decibels.

82. The optical assembly of claim 76 wherein the input beam exits the first resonant element as a first pass, element adjusted beam, and wherein the optical assembly includes a redirector assembly which redirects the first pass, adjusted beam back into the first resonant element, and wherein a second pass, adjusted beam exits the first resonant element.

83. The optical assembly of claim 82 wherein the input beam has a first polarization, and the redirector assembly includes a polarization adjuster that adjusts the polarization of the first pass, adjusted beam to be a second polarization prior to being redirected back into the first resonant element to create the second pass, adjusted beam.

84. The optical assembly of claim 83 further comprising an output polarization filter that receives the second pass, adjusted beam, wherein the output polarization filter transmits light at the second polarization and blocks light at the first polarization.

85. The optical assembly of claim 84 further comprising an input polarization filter that receives the input beam, wherein the input polarization filter transmits light at the first polarization and blocks light at the second polarization.

86. The optical assembly of claim 76 wherein the input beam exits the first resonant element as a first pass, adjusted beam, and wherein the resonant element assembly includes a second resonant element that receives the first pass, adjusted beam to create a second pass adjusted beam when the second resonant element is vibrated.

87. The optical assembly of claim 86 wherein the orientation of the second resonant element is inverted from the orientation of the first resonant element.

88. The optical assembly of claim 76 further comprising an output polarization filter that receives the beam that exits the output polarization adjuster, wherein the output polarization filter transmits light at the output polarization and blocks other polarizations.

89. The optical assembly of claim 76 further comprising an output fiber assembly that receives the adjusted beam, wherein the output fiber assembly includes an optical fiber having a fiber inlet facet that receives the adjusted beam, and a fiber cap that covers the inlet facet.

90. The optical assembly of claim 76 further comprising an input fiber assembly that launches the laser beam, wherein the input fiber assembly includes an optical fiber having a fiber outlet facet that launches the laser beam, and a fiber cap that covers the fiber outlet facet.

91. The optical assembly of claim 76 further comprising an integrated measurement system that receives a measurement beam that exits the resonant element assembly.

92. The optical assembly of claim 76 wherein the resonant element assembly further comprises an element mounting assembly that retains the first resonant element in a symmetrical fashion.

93. The optical assembly of claim 76 wherein the resonant element assembly includes a reflector side that reflects vibration energy in a symmetrical fashion.

94. The optical assembly of claim 76 further comprising a beam trap that receives unwanted light, wherein the beam trap is designed to repeatedly scatter the received unwanted light in a spiral channel.

95. An optical assembly that receives an input beam, and selectively provides an adjusted beam, the optical assembly comprising: a resonant element assembly that receives the input beam, the resonant element assembly including a first resonant element; a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly, wherein the frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly; and an integrated measurement system that receives a measurement beam that exits the first resonant element.

96. The optical assembly of claim 95 wherein the input beam is collimated.

97. The optical assembly of claim 95 further comprising an input lens assembly that collimates the input beam to create a collimated input beam that is directed at the first resonant element.

98. The optical assembly of claim 95 wherein the beam makes at least two passes through the first resonant element to form the adjusted beam.

99. The optical assembly of claim 95 wherein the first transducer has a transducer width, and the first resonant element has an element width, and wherein the transducer width is at least forty percent of the element width.

100. The optical assembly of claim 95 having an extinction-ratio of at least eighty decibels.101 . The optical assembly of claim 95 wherein the input beam exits the first resonant element as a first pass, element adjusted beam, and wherein the optical assembly includes a redirector assembly which redirects the first pass, adjusted beam back into the first resonant element, and wherein a second pass, adjusted beam exits the first resonant element.

102. The optical assembly of claim 95 wherein the measurement system includes a frequency discriminator that compares two different order beams that exit the first resonant element.

103. The optical assembly of claim 95 wherein the measurement system determines a first characteristic of the measurement beam.

104. The optical assembly of claim 103 wherein the first characteristic is selected from the group including power, frequency, and polarization of the measurement beam.

105. An optical assembly that receives an input beam, and selectively provides an adjusted beam, the optical assembly comprising: a resonant element assembly that receives the input beam, the resonant element assembly including a first resonant element, and an element mounting assembly that retains the first resonant element in a symmetrical fashion; a frequency generator that selectively directs a frequency through the resonant element assembly to selectively adjust the characteristics of the adjusted beam that exits the resonant element assembly, wherein the frequency generator includes a first transducer that is coupled to the first resonant element, and a signal generator that directs an electric signal to the first transducer to selectively vibrate the resonant element assembly.

106. A beam trap that receives unwanted light, the beam trap comprising: a trap housing that forms a spiral channel that receives the unwanted light and repeatedly scatters the unwanted light, wherein the beam trap has no surfaces at normal incidence.

Images