Power Monitoring in Fiber-Coupled Laser Systems

Abstract

Some embodiments can include a power monitor for measuring the power of laser light propagating in a core of the optical fiber, the power monitor using an optical sensor having a light sensitive section with no line of sight to the portion of the optical fiber to generate a sensor signal, the sensor signal being obtained from light emerging laterally from the portion of the optical fiber. Other embodiments may be disclosed and / or claimed.

Description

[Technical field]

[0001]

[0001] This application is a nonprovisional application of, and claims the benefit of priority to, U.S. Provisional Application Serial No. 63 / 336950, filed April 29, 2022, which is incorporated herein by reference in its entirety.

[0002] This disclosure relates to fiber-coupled laser systems, and some embodiments relate to power monitoring in laser systems. [Background technology]

[0003]

[0003] Laser systems are widely used in industrial processes (e.g., cutting, welding, cladding, heat treatment, etc.). In some laser systems (e.g., fiber lasers), the optical gain medium includes one or more active optical fibers having a core doped with rare earth element(s). The rare earth element(s) can be optically excited ("pumped") by light from one or more semiconductor laser sources.

[0004]

[0004] Various applications may benefit from monitoring one or more characteristics of the laser light, such as by using a photodetector to generate an electrical signal representative of the power of the laser light. US Patent No. 6,265,710 describes power monitoring based on capturing light emerging laterally from a glass fiber with a photodetector disposed next to the side of the glass fiber. This is done by configuring the photodetector so that its light-sensitive surface is located in a plane that is next to the glass fiber and extends parallel to the longitudinal direction of the glass fiber. In other words, the photodetector faces the fiber such that a line of sight (LOS) to the fiber (e.g., to a first side of the fiber) is provided.

[0005]

[0005] A photodetector positioned with an LOS to the fiber can directly capture light emerging laterally from the glass fiber, i.e., "laterally emerging direct light," which travels unobstructed along an optical path extending directly from a first side of the fiber to the photodetector facing the fiber. If the amount of laterally emerging direct light is not sufficient, the '710 patent provides that light emerging laterally from a second, opposite side of the glass fiber can also be captured with a photodetector facing the fiber by placing a reflector, such as a polished metal plate or a mirror-coated glass plate, on the opposite side of the fiber.

[0006]

[0006] U.S. Patent No. 8,988,669 teaches a photodetector placed "close" to the fiber to capture the laterally exiting light. Like the '710 patent, the '669 patent teaches a photodetector configuration with LOS to the fiber. This is illustrated in Figure 4 of the '669 patent.

[0007]

[0007] The accompanying drawings, in which like reference numerals represent like elements, are incorporated in and constitute a part of this specification and together with the description, explain the advantages and principles of the technology disclosed herein. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic cross-sectional view of a power monitor for a fiber-coupled laser system, in accordance with various embodiments. [Diagram 2] FIG. 2 is a schematic plan view of the interior of the power monitor of FIG. [Diagram 3] FIG. 3 is another schematic cross-sectional view of the power monitor of FIG. 1 illustrating the light path during operation of the fiber-coupled laser system. [Figure 4] FIG. 4 is a schematic cross-sectional view of another power monitor in which the enclosure can be an integrated volume. [Diagram 5] FIG. 5 is a schematic plan view of the interior of a power monitor having an optical obstruction providing lateral clearance, according to various embodiments. [Figure 6] FIG. 6 is a schematic cross-sectional view of a power monitor having a translucent optical obstruction completely separating the enclosure, in accordance with various embodiments. [Figure 7] FIG. 7 is a schematic cross-sectional view of another power monitor using the semi-transparent light obstruction of FIG. 6, in accordance with various embodiments. [Figure 8] FIG. 8 illustrates a process of generating one or more measurements of laser light emitted from at least one laser source of a fiber-coupled laser system using any power monitor or other fiber-encapsulated measurement system employing any of the principles described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009]

[0016] As used in this specification and claims, the singular forms "a," "an," and "the" include the plural unless the context clearly indicates otherwise. Furthermore, the term "comprises" means "comprising." Furthermore, the term "combined" does not exclude intermediate elements between the combined items. The systems, apparatus, and methods described herein should not be construed as limiting in any way. Rather, the present disclosure is directed to all novel and non-obvious features and configurations of the various disclosed embodiments, either alone or in combination and subcombination with each other. The term "or" refers to "and / or" and not to "exclusive or" (unless specifically indicated).

[0010]

[0017] The disclosed systems, methods, and apparatus are not limited to any particular configurations or features or combinations thereof, nor are the disclosed systems, methods, and apparatuses required to exhibit any particular advantage or solve any particular problem. Any theory of operation is for ease of explanation, and the disclosed systems, methods, and apparatuses are not limited to such theory of operation. Although operations of some of the disclosed methods are described in a particular order for ease of illustration, it should be understood that such description includes rearrangements, unless a particular order is required by specific descriptions below. For example, operations described in a sequence may be rearranged or performed simultaneously in some cases. Moreover, for simplicity, the accompanying drawings may not show various ways in which the disclosed systems, methods, and apparatuses can be used in conjunction with other systems, methods, and apparatuses.

[0011]

[0018] Moreover, the description sometimes uses terms such as "make" and "provide" to describe the disclosed methods. These terms are high-level abstractions of actual operations that are performed. The actual operations that correspond to these terms will vary depending on the particular implementation and are readily discernible to one of ordinary skill in the art. In some instances, values, procedures, or devices are described as being "lowest," "best," "minimum," etc. It will be understood that such descriptions are intended to indicate that selections may be made among the many functional alternatives employed, and that such selections are not necessarily preferred over better, lesser, or other selections.

[0012]

[0019] The examples are described with reference to orientations such as "top," "bottom," "upper," "lower," etc. These terms are used for ease of description and do not imply any particular spatial orientation.

[0013]

[0020] The fiber-enclosing measurement systems (e.g., power monitors) described herein can measure one or more characteristics (e.g., power) of laser light of a laser system more accurately than some known power monitors. Some fiber-enclosing measurement systems described herein can include an integrating volume or other enclosure for spatially homogenizing light exiting a surface (e.g., from a side of an optical fiber coupled to a laser system) of an optical fiber coupled to the laser system. The interior of the integrating volume or other enclosure can define one or more light processing surfaces for processing the exiting light and for directing the processed light to a light-sensitive section of an optical sensor (e.g., a photosensor). Sensing the processed light (e.g., spatially homogenized light) can reduce sensitivity to polarization compared to some known power monitors that monitor power using light exiting a surface (e.g., unprocessed light).

[0014]

[0021] In various embodiments, the fiber-encapsulated measurement system can be configured such that there is no line of sight from the light-sensitive section of the optical sensor to the surface of the optical fiber, which prevents light emerging from the surface (unprocessed light) from reaching the light-sensitive section of the optical sensor. Also, the power monitor can be placed in an enclosure (e.g., a light-tight enclosure) that prevents external light (e.g., ambient light) from reaching the light-sensitive section of the optical sensor. Thus, the light-sensitive section can accurately measure the power of the laser light using processed light provided by the light-processing surface(s).

[0015]

[0022] In some embodiments, one or more walls or other light obstructions including a non-transparent material may be provided in the enclosure to block the line of sight from the light-sensitive section to the surface of the optical fiber. In various embodiments, the light obstruction may include a wall or other baffle that may be formed at least in part of a non-transparent plastic such as polytetrafluoroethylene (PTFE). In some embodiments, the light obstruction(s) may divide the enclosure into a first section that includes a portion of the optical fiber and a second section that includes the light sensor, which may act to limit the light received at the light-sensitive section of the light sensor to light that has been redirected two or more times.

[0016]

[0023] Any power monitor described herein: A fiber-coupled laser system that may use one or more fiber lasers (wherein the source of the laser light is an optical fiber doped with a rare earth element); any other laser source now known or later developed, such as a fiber-coupled laser system that may use one or more lasers having any optical gain medium; It can be used in any fiber-coupled laser system, including

[0017]

[0024] A fiber-coupled laser system can use an optical fiber coupled to a fiber-based or other laser source to propagate laser light generated by a laser source downstream. In any fiber-coupled laser system, a housing can enclose at least a portion of the optical fiber coupled to the fiber-based or other laser source, and the housing can include at least one light processing surface for processing light exiting a lateral side of the coupled optical fiber. In some embodiments, the laser source can include more than one individual laser source, each of which can have a downstream optical fiber and a power monitor coupled thereto.

[0018]

[0025] Figure 1 is a schematic cross-sectional view of a power monitor 100 for a laser system, according to various embodiments. Figure 2 is a schematic plan view of the interior of the power monitor 100 of Figure 1. Figure 3 is another schematic cross-sectional view of the power monitor 100 of Figure 1, illustrating the light path during operation of the laser system.

[0019]

[0026] 1, the power monitor 100 can include an enclosure 10 that contains a portion of the active optical fiber 18 of the laser system. In some embodiments, the enclosure 10 can be an integrated volume, as described below with reference to FIGURE 4. Referring again to FIGS. 1-3, when the laser system is in operation, light 31 (FIG. 3) emerges laterally from the side of the active optical fiber 18.

[0020]

[0027] The enclosure 10 may further include an optical sensor 15 (e.g., a photosensor), which may be any optical sensor now known or developed in the future. The optical sensor 15 may generate an electrical signal indicative of one or more characteristics of the laser light in the core 19 of the optical fiber 18. The electrical signal is interpreted by processing circuitry 99 coupled to the optical sensor 15 (to derive measurement data from the sensor signal), and the measurement data may then be stored and / or used to adjust the laser system to the needs of the application.

[0021]

[0028] In contrast to some known power monitors, in power monitor 100, there is no line of sight from light sensitive section 16 (e.g., light sensitive surface, volume, etc.) of optical sensor 15 to the side of the enclosed portion of optical fiber 18. In this embodiment, light sensitive section 16 does not face optical fiber 18, although this facing arrangement may not be required in other embodiments.

[0022]

[0029] To obstruct the line of sight, in this embodiment, one or more light obstructions 12 (e.g., non-transparent walls in this example) may be positioned laterally adjacent to the optical fiber 18, for example, between the light sensor 15 and the optical fiber 18. The light obstruction 12 may be a non-transparent structure that may block the line of sight from the light sensitive section 16 of the light sensor 15 to the side of the optical fiber 18. In another embodiment, it may be possible and practical to block the line of sight based on the placement of the light sensor 15 in the enclosure and / or the shape of the cavity, so a light obstruction(s) may not be necessary in such an embodiment.

[0023]

[0030] Light obstruction 12 can be formed from a single material or a combination of materials. In various embodiments, the material(s) of light obstruction 12 can include a translucent or opaque material, such as a non-transparent plastic, e.g., polytetrafluoroethylene (PTFE), etc. In some embodiments, any material (non-transparent or otherwise) may be coated with a non-transparent coating (e.g., a translucent coating) that can redirect and / or process the raw light 31 (FIG. 3) emerging from the side of optical fiber 18.

[0024]

[0031] In this embodiment, a gap 14 is provided between a portion of the light obstruction 12 (e.g., in this embodiment, the top of the light obstruction 12) and a light processing surface 11 within the enclosure 10 (e.g., at least a portion of an interior surface of the enclosure 10). The gap 14 allows processed light 32 (FIG. 3) to reach a portion of the enclosure where a light sensor 15 may be located.

[0025]

[0032] In various embodiments, the light obstruction 12 may divide the interior cavity of the enclosure 10 into a first section and a second distinct section. The first original light emerging from a portion of the optical fiber may be provided only in the first section of the first and second sections. All the light in the second section may be second light emerging from the gap (e.g., second light derived from the first light). In some embodiments, the second section may be larger (e.g., have a larger volume) than the first section, although of course this is not required.

[0026]

[0033] The light processing surface 11 may be a diffuse reflecting surface. In contrast to a specular reflecting surface (e.g., a polished metal plate or a mirror-coated glass plate used in some known power monitors), the diffuse reflecting surface may be ground or roughened. Figure 3 illustrates the diffuse reflection by the light processing surface 11 to produce processed light 32.

[0027]

[0034] 4 is a schematic cross-sectional view of another power monitor 400 in which the enclosure 410 can be an integrating volume. An integrating volume is an optical device that includes a hollow cavity having a diffusely reflective interior. While some known integrating volumes are spherical and have a diffusely reflective coating covering the entire interior of the sphere, the integrating volumes described herein can be of any shape (spherical or otherwise) in which at least a portion of the interior of the integrating volume can be a diffusely reflective surface.

[0028]

[0035] 4 illustrates that power monitor 400 can include more than one diffuse reflective surface. For example, as illustrated, at least one surface of light obstruction 412 can be diffuse reflective surface 414 for processing the exiting light. Also, as illustrated, the interior of enclosure 410 can include diffuse reflective surface 416.

[0029]

[0036] The diffuse reflective surface 416 can redirect the processed light exiting the gap 14. As illustrated, the diffuse reflective surface 416 can further process the processed light 32 exiting the gap 14. Due to the section 416 on the opposite side of the optical fiber 18 in the cavity and the lack of line of sight (made so in this embodiment by the optical obstruction 412), in this embodiment the light sensitive section 16 can be exposed only to the processed light more than once. This can be beneficial in some applications compared to power monitoring where the light sensitive section is exposed to an unprocessed portion of the exiting light and / or only processed light once.

[0030]

[0037] In one embodiment, the enclosure cavity may have the shape of a spherical segment to optimize the amount of diffusely reflected light reaching the light-sensitive section 16 of the light sensor 15 using a minimum volume of space. In those embodiments, at least a portion of the dome interior (e.g., some or all of the dome interior) may be a diffusely reflective surface. In other embodiments, it may be practical and possible to have a faceted dome interior or some other interior that has one or more flat surfaces, and at least a portion of at least some of the flat surfaces may be a diffusely reflective surface.

[0031]

[0038] In one embodiment, some of the advantages of the spherical segments are that a low profile can be provided by using a stadium segment shape for the dome interior. This is shown in the cross-sectional view illustrated in the '950 provisional application, where the dome interior has one flat surface extending from the first section to the second section, and two curved surfaces (e.g., arcs such as 90 degree arcs or any other linear or non-linear slope) corresponding to the first and second sections of the cavity, respectively.

[0032]

[0039] 5 is a schematic plan view of the interior of a power monitor 500 having a light obstruction 512 providing side gaps 514A and 514B, according to various embodiments. As illustrated, in various embodiments, side gap(s) 514A and / or 514B can be provided between a side of the enclosure and a side of the light obstruction 512. The gap(s) 514A and / or 514B can be provided in addition to, or instead of, a gap similar to gap 14 (FIG. 1). Providing gaps to the sides and above the enclosure can increase the amount of light sampled by light sensor 15, which can be advantageous in some embodiments.

[0033]

[0040] To further increase the amount of light sampled by the light sensor 15, in this embodiment the light sensor 15 is placed on the side of the enclosure rather than on the bottom of the enclosure as in the previously described embodiment, such that the light sensitive section 16 of the light sensor 15 faces the optical fiber 18. When so positioned, the light obstruction 512, the dimensions of the enclosure, and / or the size of the light sensitive section 16 may be selected, if required for a given application, to ensure that all light received by the light sensitive section 16 does not have a single bounce path.

[0034]

[0041] Figure 6 is a schematic cross-sectional view of a power monitor 600 having a translucent optical obstruction 612 that completely separates the enclosure (e.g., has no gaps), according to various embodiments. Figure 7 is a schematic cross-sectional view of another power monitor 700 that uses the translucent optical obstruction of Figure 6, according to various embodiments.

[0035]

[0042] In the embodiment illustrated in Figures 6 and 7, all light (not shown) reaching the light sensor 15 passes through the diffusely transmitting translucent material of the translucent light obstruction 612. Because there is no gap, the light sensor 15 does not have a line of sight to the optical fiber 18 at any sensor location in the second section of the enclosure (e.g., the bottom of the enclosure illustrated in Figure 6 or the side of the enclosure illustrated in Figure 7). In both the embodiments illustrated in Figures 6 and 7, all light reaching the light sensor 15 is scattered inside the diffuser (e.g., the translucent light obstruction 612) and may be processed more than once.

[0036]

[0043] In the embodiments described herein, the light emerging from the side of the optical fiber may have a polarization / direction that varies over time. One or more light processing surfaces within the enclosure may be arranged to process the light, which may remove its spatial information, making it less sensitive to polarization than some known power monitors. The processing by the light processing surfaces within the enclosure may be diffusive (e.g., diffuse reflection), although in other instances it may be possible and practical to arrange the light processing surface(s) to provide some other form of light processing instead of or in addition to diffuse reflection.

[0037]

[0044] In any power monitor, the processing circuitry may include a general purpose processor and hardware memory for storing instructions executable by the general purpose processor, or some other circuitry, such as an application specific processor. The processing circuitry may consume raw data (e.g., sensor signal) output by the light sensor and may output data derived from the raw data. The output data may be generated using any laser system monitoring algorithm now known or later developed, and in some embodiments may include a control signal for adjusting operation of the laser system based on the measured output power of light sampled by the light sensor (e.g., processed light reaching a light sensitive section of the light sensor).

[0038]

[0045] It should be understood that a fiber-coupled laser system may have any number of individual laser sources. For example, in some fiber-coupled laser systems, a combiner receives the laser light generated from the different individual laser sources and outputs a combined laser light. Various embodiments of the power monitor described herein may be used anywhere downstream of the individual laser sources, such as upstream of the combiner (where the power monitor may generate measurements corresponding to each of the individual laser sources) and / or downstream of the combiner (where the power monitor may generate measurements corresponding to the combined laser light). In some embodiments, a cladding light stripper may be provided upstream of the power monitor enclosure (e.g., outside of the enclosure) to remove light carried in the cladding of the optical fiber, such that light emerging from the portion of the optical fiber enclosed by the power monitor originates from the core of the optical fiber.

[0039]

[0046] 8 illustrates a process 800 for generating one or more measurements of laser light emitted from at least one laser source of a fiber-coupled laser system using any power monitor or other fiber-encapsulated measurement system employing any of the principles described herein. In block 801, laser light is caused to propagate within a core of an optical fiber of the fiber-coupled laser system, and a first light is caused to exit laterally from an outer surface of a portion of the optical fiber encapsulated by the measurement system.

[0040]

[0047] At block 802, a light sensor included in the measurement system receives the second light. A light sensitive section of the light sensor does not have line of sight to the enclosed portion of the optical fiber, and the second light is derived from the first light. In some embodiments, the second light may be processed more than once by a light processing surface within the enclosure.

[0041]

[0048] At block 803, the light sensor can generate a sensor signal in response to receiving the second light. At block 804, the light sensor can output the sensor signal to a processing circuit coupled to the light sensor. At block 805, the processing circuit can generate one or more measurements of the laser light using the processing circuit. In various embodiments, the one or more measurements can be stored in hardware memory of the processing circuit, sent to a remote processor, used to generate a control signal to adjust one or more operating parameters of the fiber coupled laser system, and / or the like.

[0042]

[0049] The housing with an internal cavity can collect or integrate the scattered light from the fiber while preventing the photodiode from seeing the first bounce from the fiber. Various embodiments have the following features associated with producing a higher signal-to-noise ratio (signal-to-noise ratio = the amount of signal received by the sensor relative to stray ambient light leaking into the integration volume, or noise generated in the wire from electric fields): The housing can have a higher view-to-scatter ratio (the amount of surface area the sensor is positioned to view compared to the surface area illuminated by scattered light from the fiber) than previous approaches. Allows for a larger photodiode surface area than power monitors, which may have a requirement for "proximity" of the optical sensor to the optical fiber Both light shielded and fully encapsulated designs can contribute to blocking a high percentage of ambient light. The present invention may have one or more of the following:

[0043]

[0050] Some embodiments have the following features: Exposed fiber length = 7-9mm (some previous approaches may have exposed fiber lengths of 12.7mm) Cavity volume of approximately 560mm^3 (some previous approaches can have exposed cavity volume of approximately 1177mm^3) Upper dome surface area = 285.3mm^2 to minimize cavity volume requirements (some previous approaches may have an area for view of approximately 20mm^3) Total integrated area of ​​about 600mm^2 (some previous approaches may have a total integrated area of ​​about 477mm^2) View ratio = 23-45% depending on baffle design (some earlier approaches have a view ratio of 4%) The present invention may have one or more of the following:

[0044]

[0051] Any of the power monitors described here a fiber-coupled laser system that may use one or more fiber lasers, in which the source of laser light is an optical fiber doped with a rare earth element; and Any other laser source now known or later developed, such as a fiber-coupled laser system that may use one or more lasers having any optical gain medium. It can be used in any fiber-coupled laser system, including

[0045]

[0052] A fiber-coupled laser system can use an optical fiber coupled to a fiber-based or other laser source to propagate laser light generated by a laser source downstream. In any fiber-coupled laser system, a housing can enclose at least a portion of the optical fiber coupled to the fiber-based or other laser source, and the housing can include at least one light processing surface for processing light exiting a lateral side of the coupled optical fiber. In some embodiments, the laser source can include more than one individual laser source, each of which can have a downstream optical fiber and a power monitor coupled thereto.

[0046]

[0053] In view of the many possible embodiments to which the principles of the disclosed technology can be applied, it should be recognized that the illustrated embodiments are merely preferred examples and should not be treated as limiting the scope of this disclosure.

Claims

1. An apparatus comprising:

1. A power monitor for measuring the power of laser light propagating through a core of an optical fiber, comprising: a power monitor for generating a sensor signal using an optical sensor having a light sensitive section with no line of sight to a portion of the optical fiber; An apparatus wherein the sensor signal is derived from light emerging laterally from the portion of the optical fiber.

2. 2. The apparatus of claim 1, wherein the power monitor outputs the sensor signal to a processing circuit coupled to the optical sensor.

3. 3. A fiber coupled laser system using the power monitor of claim 2, wherein the optical fiber is coupled to a laser source that generates the laser light.

4. 4. The apparatus of claim 3, wherein the processing circuitry generates a control signal for adjusting one or more operating characteristics of the fiber coupled laser system based on the measured power.

5. 2. The apparatus of claim 1, wherein the optical sensor is positioned such that the light sensitive section does not face the portion of the optical fiber; or the power monitor comprising a non-transparent optical obstruction having a surface facing the portion of the optical fiber, the non-transparent optical obstruction being positioned between the portion of the optical fiber and the light-sensitive section of the light sensor.

6. 1. A method for measuring power or one or more other characteristics of laser light propagating in a core of an optical fiber of a fiber-coupled laser system based on a first light emerging laterally from a portion of the optical fiber, comprising: receiving a second light by a light sensor, the light sensitive section of the light sensor having no line of sight to the portion of the optical fiber, the received second light being derived from the first light; generating a sensor signal by the optical sensor in response to receiving the second laser light; outputting the sensor signal to a processing circuit coupled to the optical sensor; A method comprising:

7. 7. The method of claim 6, further comprising the step of generating a control signal for the fiber coupled laser system using the processing circuitry.

8. 7. The method of claim 6, further comprising the step of storing an output of the processing circuitry in a hardware memory.

9. 7. The method of claim 6, further comprising at least partially dividing an enclosure into a first section and a second section, the portion of the optical fiber being located in the first section of the enclosure and the optical sensor being located in the second section of the enclosure.

10. 7. The method of claim 6, further comprising at least partially dividing an integrated volume into a first section and a second section, the portion of the optical fiber being located in the first section of the integrated volume and the optical sensor being located in the second section of the integrated volume.

11. 1. A power monitor for measuring the power of laser light propagating through a core of an optical fiber, comprising: an enclosure, the optical fiber disposed through the enclosure, the first light exiting laterally from an enclosed portion of the optical fiber; 1. A light sensor comprising a light sensitive section, an optical sensor, the optical sensitive section having no line of sight to the optical fiber, the optical sensor receiving a second light derived from the first light and generating a sensor signal in response to the received second light; a processor coupled to the optical sensor, receiving the sensor signal; Deriving measurement data from the sensor signals; a processor, wherein the measurement data includes the power measured for the laser light propagating through the core of the optical fiber; and A power monitor comprising:

12. 12. The power monitor of claim 11, further comprising: an optical obstruction disposed within the enclosure between the portion of the optical fiber and the optical sensor; the optical obstruction divides the enclosure into a first section including the optical fiber and a second section including the optical sensor; The power monitor, wherein the optical obstruction receives a portion of the first light, thereby preventing the line of sight from the light sensitive section to the portion of the optical fiber.

13. 12. The power monitor of claim 11 further comprising: the enclosure includes a first section including the portion of the optical fiber and a second section including the optical sensor; the light sensitive section of the light sensor does not face the portion of the optical fiber, thereby preventing the line of sight from the light sensitive section to the portion of the optical fiber.

4. A power monitor comprising:

14. 12. The power monitor of claim 11, further comprising: A power monitor comprising at least one light processing surface for processing said first light and transmitting said second light, said at least one light processing surface being ground or roughened.

15. 12. The power monitor of claim 11, further comprising: A power monitor comprising at least one light processing surface for processing the first light and directing the second light, the at least one light processing surface comprising a diffusely reflective surface.

16. 16. The power monitor of claim 15, wherein the at least one optical processing surface comprises an interior portion of the enclosure.

17. 17. The power monitor of claim 16, wherein the at least one light processing surface includes a plurality of light processing surfaces including the portion of the interior of the enclosure and a portion of an optical obstruction disposed within the enclosure between the portion of the optical fiber and the optical sensor.

18. 13. The power monitor of claim 12, wherein the optical obstruction comprises: A translucent wall or other translucent object, or a non-transparent wall or other non-transparent object, Including, A power monitor wherein the optical obstruction is formed from a translucent plastic or other non-transparent material or includes a translucent or other non-transparent surface facing the portion of the optical fiber.

19. 13. The power monitor of claim 12, further comprising a gap between a portion of the light obstruction and a portion of an interior of the enclosure, the second light being received through the gap.

20. 16. The power monitor of claim 15, wherein the at least one optical processing surface is disposed on an internal planar surface of the enclosure.

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