Optical Assembly

Abstract

A method for connecting an optical element to a mount, the method including: attaching a connector to the optical element with a first solder and heating the first solder with an ultrasonic heater to form a first soldered joint between the connector and the optical element; aligning the optical element within an inner opening of the mount; and attaching the connector to the mount with a second joint, wherein the first soldered joint is a polymer-free joint.

Description

[Technical Field]

[0001] This application claims the benefit of priority to U.S. Provisional Application No. 63 / 423,203, filed November 7, 2022, the contents of which are relied upon and incorporated by reference herein in their entirety.

[0002] The present disclosure relates to optical element assemblies, and more particularly to optical mounts that are coupled to optical elements using polymer-free joints. [Background technology]

[0003] Optical elements, such as precision lenses, are secured in optical mounts for use in lithography equipment. Compliant materials are typically used to provide a joint between the optical element and the optical mount, securing the two components together. The compliant material should be flexible enough to reduce deformations induced on the optical element by the optical mount. More specifically, deformations caused by mechanical stress or thermal strain in the optical mount. Traditionally, compliant materials are organic polymers due to their ability to bond to both the optical element and the optical mount. Some traditional organic polymers include organic adhesives, such as epoxy resins or cyanoacrylate resins.

[0004] However, the use of organic polymers creates contamination problems that degrade the performance of the optical elements over time. In some conventional systems, the optical elements and optical mounts are maintained at special atmospheric conditions to reduce the degradation of the organic polymers. However, the requirement for such special atmospheric conditions can be very expensive. Summary of the Invention

[0005] Therefore, a need exists for reliably attaching an optical element to an optical mount without relying on polymer-based joints. Embodiments of the present disclosure are directed to a polymer-free joint between an optical element and an optical mount. In particular, embodiments of the present disclosure create a solder joint between the optical element and the optical mount, thus allowing the two components to be reliably fastened while avoiding any such contamination issues associated with polymer-based joints. Furthermore, a connector may be used to provide the link connecting the optical element and the optical mount.

[0006] According to an aspect of the disclosure, a method for connecting an optical element to a mount is disclosed. The method includes attaching a connector to the optical element with a first solder and heating the first solder with an ultrasonic heater to form a first solder joint between the connector and the optical element, aligning the optical element within an inner opening of the mount, and attaching the connector to the mount with a second joint. The first solder joint is a polymer-free joint.

[0007] According to an aspect of the disclosure, an optical assembly is disclosed, the assembly comprising: a mount; an optical element disposed within an inner opening of the mount; and one or more connectors attached to the optical element via solder joints, the solder joints being polymer-free joints constructed from one or more metal alloys. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a schematic diagram of an optical assembly according to an embodiment of the present disclosure. [Figure 2] FIG. 1 is a top view of a schematic diagram of an optical assembly according to an embodiment of the present disclosure. [Figure 3A] FIG. 2 is a close-up view of an optical element, a connector, and a mount according to an embodiment of the present disclosure. [Figure 3B] FIG. 10 is another enlarged view showing the interface between the optical element, the connector, and the mount, according to an embodiment of the present disclosure. [Figure 4] FIG. 10 is another perspective view of a schematic diagram of an optical assembly according to an embodiment of the present disclosure. [Figure 5A] 1A-1C are schematic diagrams of a process for forming a bond using an ultrasonic heater according to an embodiment of the present disclosure. [Figure 5B] FIG. 1 is a schematic diagram of a bond formed using an ultrasonic heater according to an embodiment of the present disclosure. [Figure 5C] 1 is a schematic diagram illustrating an adhesion-promoting coating on a surface of an optical element, connector, or mount according to an embodiment of the present disclosure. [Figure 6] 1 illustrates a process for forming an optical assembly according to an embodiment of the present disclosure. [Figure 7] FIG. 1 is a schematic diagram of multiple connectors attached to an optical element, according to an embodiment of the present disclosure. [Figure 8] FIG. 1 is a top view of a schematic diagram of an optical assembly and alignment device according to an embodiment of the present disclosure. [Figure 9] A and B are images of the solder joint formed between the optical element and the connector. DETAILED DESCRIPTION OF THE INVENTION

[0009] Additional features and advantages of the present disclosure will be set forth in the following detailed description, and will become apparent to those skilled in the art from the description, or may be learned by practicing the invention as set forth in the following description, taken in conjunction with the claims and accompanying drawings.

[0010] As used herein, the term "and / or," when used in a list of two or more items, means that any one of the listed items can be employed alone, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and / or C, the composition can contain A only, B only, C only, a combination of A and B, a combination of A and C, a combination of B and C, or a combination of A, B, and C.

[0011] In this document, relational terms such as first and second, top and bottom, etc. are used solely to distinguish one entity or action from another, without necessarily requiring or implying any such actual relationship or order between such entities or actions.

[0012] It will be understood by those skilled in the art that the structures of the disclosures and other components described are not limited to any particular materials. Other exemplary embodiments of the disclosures disclosed herein may be formed from a variety of materials unless otherwise described herein.

[0013] It is also important to note that the structure and arrangement of elements of the present disclosure as shown in the exemplary embodiments are merely illustrative. While only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that numerous modifications (e.g., size, dimensions, structure, shape, and proportions of various elements, parameter values, mounting configurations, use of materials, color, orientation, etc.) are possible without materially departing from the novel and unobvious teachings and advantages of the recited subject matter. For example, elements shown as integrally formed may be constructed of multiple pieces, or elements shown as multiple pieces may be integrally formed, interface operation may be reversed or otherwise altered, the structure and / or members of the system, or the length or width of connectors or other elements, may be altered, and the nature or number of adjustment positions provided between elements may be changed. It should be noted that the elements and / or assemblies of the system may be constructed from any of a variety of materials that provide sufficient strength or durability in any of a variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be within the scope of the present disclosure. Other substitutions, modifications, changes, and omissions may be made to the desired design, operating conditions, and arrangements, as well as other exemplary embodiments, without departing from the spirit of the present disclosure.

[0014] Reference will now be made in detail to the exemplary embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[0015] 1 , an optical assembly 10 is shown that includes an optical element 20 secured to a mount 30. A plurality of connectors 40 may connect the optical element 20 to the mount 30. In an embodiment, the optical assembly 10 does not include a polymer joint for connecting the optical element 20 with the mount 30. Thus, the connection between the optical element 20 and the mount 30 is polymer-free. Instead, the connectors 40 may connect to each of the optical element 20 and the mount 30 through an ultrasonic soldering process.

[0016] In embodiments, optical element 20 may be a lens, a mirror, or a prism. In embodiments, optical element 20 is composed of glass, glass ceramic, or ceramic. Glass and glass-ceramic materials include, for example, silicate glass, aluminosilicate glass, alkali aluminosilicate glass, alkali aluminosilicate glass, borosilicate glass, boroaluminosilicate glass, alkali aluminoborosilicate glass, alkali aluminoborosilicate glass, soda-lime glass, fused silica, or other types of glass. Exemplary glass materials include, but are not limited to, high-purity fused silica HPFS® sold by Corning Incorporated of Corning, New York, and EAGLE XG® boroaluminosilicate glass, also sold by Corning Incorporated of Corning, New York. Other glass substrates include, but are not limited to, ultra-low expansion ULE® glass, Lotus™ NXT glass, Iris™ glass, WILLOW® glass, GORILLA® glass, VALOR® glass, Vycor™ glass, or PYREX® glass, all sold by Corning Incorporated of Corning, New York. In some embodiments, optical element 20 is made of float glass, such as soda-lime glass. In some embodiments, optical element 20 is made of magnesium fluoride and / or calcium fluoride. In still other embodiments, optical element 20 is made of silica glass having 80% or more by weight silica, or 85% or more by weight silica, or 90% or more by weight silica, or 95% or more by weight silica, or 99% or more by weight silica.

[0017] Exemplary glass-ceramics include, for example, lithium disilicate, nepheline, beta-spodumene, and beta-quartz. Exemplary commercially available materials include, for example, Macor® and Pyroceram®, sold by Corning Incorporated, Corning, New York.

[0018] 1-3B, the optical element includes a top surface 21, a bottom surface 23, and at least one side surface 25. Furthermore, an outer diameter 22 of the optical element 20 (formed by the side surface 25) is less than an inner diameter 34 of the mount 30. Thus, when the optical assembly 10 is assembled, the optical element 20 is configured to fit within and be disposed within an interior portion of the mount 30. As discussed further below, when the optical assembly 10 is assembled, a gap may be provided between the side surface 25 of the optical element 20 and the mount 30. Furthermore, the optical element 20 and the mount 30 are concentric when the optical assembly 10 is assembled, as shown in FIG.

[0019] 1, the optical assembly 10 includes three connectors 40 equally spaced (e.g., by a 180° separation angle) around the optical element 20. However, it is contemplated that the optical assembly 10 may include more or fewer connectors 40, and that the connectors 40 may be spaced in a different configuration than that shown in FIG.

[0020] Mount 30 may form a donut shape having an inner diameter 34 and an outer diameter 32. Thus, mount 30 may be a ring-shaped member. In embodiments, mount 30 is constructed from a metal such as, for example, a stainless steel alloy, nickel steel, titanium, aluminum, or brass. In some embodiments, mount 30 is constructed from a glass, glass-ceramic, or ceramic, such as those described above in connection with optical element 20. As shown in FIG. 1 , a hole 36 may be formed on mount 30 for attachment to an alignment device, as discussed further below.

[0021] Mount 30 may further be assembled into an optical system, including an imaging and illumination system, such as, for example, a photolithography system, a semiconductor inspection system, a microscope assembly, or a polarization system.

[0022] 1 depicts optical element 20 and mount 30 as circular, it should be noted that one or both of these components may have other shapes. For example, in some embodiments, the periphery of mount 30 may be square.

[0023] 1 and 2, connector 40 provides an attachment between optical element 20 and mount 30. Thus, as discussed further below, connector 40 may be separately secured to both optical element 20 and mount 30. In embodiments, connector 40 may be constructed from metal, glass, glass-ceramic, or ceramic. Thus, connector 40 may be constructed from any of the materials described above in connection with optical element 20 and / or mount 30. Connector 40 may be disposed within well 38 formed in mount 30, as discussed further below.

[0024] FIG. 3A shows an enlarged view of the connector 40 before attachment to either the optical element 20 or the mount 30. FIG. 3B shows an enlarged view of the connector 40 after attachment to both the optical element 20 and the mount 30 via ultrasonic soldering. Referring to FIG. 3A, the connector 40 includes an arm 50 connected to a retainer 60. The arm 50 may form a cantilever member extending from the retainer 60. The arm 50 may further include a first end 52 connected to the retainer 60 and a second end 54. Before attachment to the optical element 20, the second end 54 of the arm 50 is a free end. The second end 54 of the arm 50 may further form a bearing surface for supporting the optical element 20. As discussed further below, the second end 54 of the arm 50 is attached to the optical element 20 via an ultrasonic soldering process. The first end 52 of the arm may be connected to the retainer 60 via any known attachment means. In some other embodiments, first end 52 and retainer 60 are a single, integral member.

[0025] Retainer 60 may include vertical openings 62 and / or horizontal openings 64 that are used for fastening to mount 30, as discussed further below. Also, as discussed below, retainer 60 may be disposed within a recess in mount 30 when optical assembly 10 is fully assembled.

[0026] Connectors 40 are sized and configured to provide a load-bearing surface for optical element 20 and to isolate optical element 20 from any mechanical stress and / or thermal strain imparted to mount 30. Thus, connectors 40 each act as a buffer to absorb any stress or strain imparted to mount 30, preventing it from reaching or affecting optical element 20. When optical assembly 10 is assembled, connectors 40 should be spaced a sufficient distance around the periphery of optical element 20 to provide such load-bearing and stress-absorbing characteristics.

[0027] While Figure 3A depicts the arm 50 of the connector 40 as a straight, rectangular member, it is contemplated that the arm 50 may have other shapes and configurations. For example, Figure 4 depicts an embodiment in which the arm 50 forms an inverted U-shaped profile between the first end 52 and the second end 54. In yet other embodiments, the arm 50 may form an L-shaped profile, an S-shaped profile, or a serpentine-shaped profile between the first end 52 and the second end 54.

[0028] 3A and 3B , the connector 40 may be attached to the optical element 20 and / or the mount 30 through one or more solder joints 70. As discussed further below, the solder joints 70 provide mechanical attachment and may be formed through an ultrasonic soldering process. In particular, the second end 54 of the arm 50 of the connector 40 may be attached to the optical element 20 through a first solder joint 72. As shown in FIG. 3B , the first solder joint 72 may directly attach the optical element 20 to the second end 54 of the arm 50 such that no other components are disposed between the optical element 20 and the arm 50 (other than the first solder joint 72 itself). In embodiments, the first solder joint 72 specifically attaches the second end 54 of the arm 50 to the side surface 25 of the optical element 20. Thus, in some embodiments, only the second end 54 of the arm 50 is directly attached to the optical element 20 via the solder joint 70. It is also contemplated that in some other embodiments, the length of arm 50 greater than second end 54 is directly attached to optical element 20 via solder joint 70 .

[0029] The retainer 60 of the connector 40 may be attached to the mount 30 through a second solder joint 74. As discussed further below, to attach the retainer 60 to the mount 30, the retainer 60 may be disposed within the recess 39 of the mount 30, and the arm 50 may be disposed within the well 38. As shown in FIGS. 3A and 3B , the recess 39 connects to the well 38 through a passage 37. The second solder joint 74 may be disposed within the vertical and horizontal openings 62, 64 to provide a direct attachment between the mount 30 and the retainer 60 of the connector 40, such that no other components (other than the second solder joint 74 itself) are disposed between the mount 30 and the retainer 60. In an embodiment, the second solder joint 74 specifically attaches the retainer 60 of the connector 40 to the bottom surface 33 of the recess 39 of the mount 30. In yet other embodiments, retainer 60 may be connected to mount 30 through different attachment means other than soldered joints. For example, retainer 60 may be attached to mount 30 through ceramic-based or polymer-based attachments.

[0030] The solder joints 70 (e.g., first solder joint 72, second solder joint 74) may be formed from solder 80 melted or heated by an ultrasonic heater 90, as shown in FIG. 5A . For example, the solder 80 may be disposed on at least a portion of a first surface 85, which may be one of the connector 40, the optical element 20, and the mount 30. Once the solder 80 is melted on the first surface 85 by the ultrasonic heater 90, a second surface 87 may be applied to the solder 80 to attach the first and second surfaces 85, 87. The solder 80 may then solidify to create the solder joint 70, thus forming an attachment between the first surface 85 and the second surface 87 through the solder joint 70 (as shown in FIG. 5B ). The second surface 87 may be one of the connector 70, the optical element 20, and the mount 30. Thus, for example, first surface 85 is connector 40 and second surface 87 is optical element 20. In other embodiments, first surface 85 is connector 40 and second surface 87 is mount 30.

[0031] It should be noted that solder 80 may be used to create a secure attachment between components formed of the same or different materials. Thus, for example, first surface 85 may be formed of a different material than second surface 87. In some embodiments, first surface 85 is formed of glass and second surface 87 is formed of metal.

[0032] The solder 80 may be composed of one or more metal alloys including, for example, tin (Sn), silver (Ag), copper (Cu), titanium (Ti), cerium (Ce), and gallium (Ga). In some embodiments, the solder 80 comprises a majority of tin (i.e., greater than about 50% by weight, or greater than about 60% by weight, or greater than about 70% by weight, or greater than about 80% by weight, or greater than about 90% by weight). Without wishing to be bound by theory, it is believed that the inclusion of titanium in the solder 80 helps bond the solder 80 to the glass, and the inclusion of cerium in the solder 80 helps prevent oxidation of the soldered joint 70. In some embodiments, the solder 80 is pre-formed into a desired shape to mate with a mating component on the connector 40.

[0033] In embodiments, the solder joints 70 may have sufficient surface area on the first and / or second surfaces 85, 87 to provide a secure attachment between the first surface 85 and the second surface 87. Note that the surface area of ​​the solder joints 70 is related to the number of connectors 40 used, with fewer connectors 40 resulting in a greater surface area per connector. The solder joints 70 in the assembled optical assembly 10 exhibit a velocity of approximately 10×9.81 m / s over a period of approximately 1 millisecond. 2 ~Approx. 50x9.81m / s 2 , or about 20 x 9.81 m / s over a period of about 1 millisecond. 2 ~About 40x9.81m / s 2 , or about 30 x 9.81 m / s over a period of about 1 millisecond. 2 ~Approx. 35x9.81m / s 2Therefore, the solder joints 70 must not break when subjected to such shock loads.

[0034] The solder joint 70 may create a bond between the first surface 85 and the second surface 87 such that the joint itself is stronger than either the first surface 85 or the second surface 87. Thus, when the assembled optical assembly 10 is subjected to, for example, torsional forces, the connector 40 will fail first before the solder joint 70. In embodiments, the solder joint 70, when attached to the glass connector 40, may withstand pressure loads of from about 1 pound per square inch (psi) to about 2,000 psi, or from about 10 psi to about 1,500 psi, or from about 100 psi to about 1,000 psi, or greater than about 100 psi, or greater than about 500 psi, or greater than about 1,000 psi, or greater than about 1,500 psi, or greater than about 2,000 psi. In embodiments, solder joint 70, when attached to metal connector 40, can withstand pressure loads of from about 1 psi to about 200,000 psi, or from about 10 psi to about 150,000 psi, or from about 100 psi to about 100,000 psi, or greater than about 100 psi, or greater than about 1,000 psi, or greater than about 10,000 psi, or greater than about 100,000 psi, or greater than about 200,000 psi.

[0035] 5A , the ultrasonic heater 90 can heat the solder 80 such that a reaction layer 82 is formed between the solder 80 and the solder 85. The reaction layer 82 can be a transition region that forms a gradient between the material of the first surface 85 and the material of the solder 80. Thus, the interface between the first surface 85 and the solder 80 can not have a clear boundary. Instead, within the reaction layer 82, the materials of the solder 80 and the first surface 82 can be interwoven with each other.

[0036] The ultrasonic heater 90 may include an oscillator that converts high-frequency electrical current into vibrational ultrasonic waves. In some embodiments, the ultrasonic heater 90 is a piezoelectric transducer. The ultrasonic heater 90 may operate at an oscillation frequency of about 10 kHz to about 100 kHz, or about 20 kHz to about 60 kHz, and may have an output power of about 10 watts to about 1,000 watts. As known in the art, the ultrasonic heater 90 may include a transducer and oscillator attached to a horn to generate the oscillation frequency. Although not shown in FIG. 5A , the tip of the ultrasonic heater 90 may include an open passage through which air can flow to cool the transducer. The ultrasonic heater 90 applies ultrasonic waves to a material (e.g., solder 80) to attach the material to the first surface 85 or the second surface 87, relying on the phenomenon of cavitation, thus forming the soldered joint 70.

[0037] Cavitation is the formation and subsequent collapse of gas bubbles in a material with a rapidly changing pressure field. More specifically, an ultrasonic heater 90 induces ultrasonic vibrations on a material (e.g., solder 80) such that the vibrations pass through the material. Specifically, these vibrations pass through the material as a series of compression and expansion waves. The compression and expansion waves create regions of relatively low and relatively high pressure within the material, thereby forming cavities within the material. The cavities are in the form of gas bubbles, which grow within the material with continued application of ultrasonic vibrations. The gas bubbles continue to grow until they reach a critical size, at which point they collapse, releasing high levels of energy and pressure, thus forming microjets. The microjets impact the surface to which the material is being attached. When the microjets impact the surface, they do so with such force that they disrupt the oxide layer on the surface. By disrupting the oxide layer, the material can bond and securely attach to the surface. In embodiments disclosed herein, the material that forms the microjet is solder 80, and the surface where the microjet breaks down the oxide layer is first surface 85 or second surface 87. In some specific embodiments, when ultrasonic waves are applied to solder 80, the solder 80 forms a microjet that breaks down the oxide layer on connector 40 made of glass. Furthermore, in some specific embodiments, when ultrasonic waves are applied to solder 80, the solder forms a microjet that breaks down the oxide layer on connector 40 made of metal. It should be noted that without the break down of the oxide layer on the glass or metal connector 40, the metal solder 80 cannot bond and attach to the glass or metal material of connector 40.

[0038] Once the material (e.g., solder 80) is secured to the surface (e.g., connector 40), the ultrasonic application is terminated, allowing the material to solidify and harden, thus forming a soldered joint 70 between the material and the surface. During ultrasonic application, the ultrasonic heater 90 may be heated to a temperature range of about 450°C or less, or about 400°C or less, or about 350°C or less, or about 100°C to about 450°C, or about 150°C to about 450°C, or about 200°C to about 450°C, or about 100°C to about 400°C, or about 150°C to about 400°C, or about 200°C to about 400°C, or about 250°C to about 400°C.

[0039] It is also contemplated that in some embodiments, the material (e.g., solder 80) may first be subjected to a preheat treatment prior to ultrasonic application. The preheat treatment may include heating the material to melt and liquefy (or at least partially liquefy) the material. Liquefying the material allows the material to more efficiently pass ultrasonic vibrations (induced by ultrasonic heater 90) throughout the material, which helps to initiate the cavitation process, as discussed above. In some embodiments, the preheat treatment includes heating the material to a temperature of about 100°C to about 300°C, or about 150°C to about 250°C, or about 200°C to about 250°C.

[0040] In some embodiments, the ultrasonic heater 90 also comprises a resistive heater that applies a preheating treatment to the material, while in other embodiments, the preheating treatment is accomplished using a heating device separate and distinct from the ultrasonic heater 90, such as, for example, conductive heating (e.g., a hot plate), convection heating, radiant heating, or induction heating.

[0041] 5C, an adhesion-promoting coating 89 may be disposed on at least one of the first surface 85 and / or the second surface 87 to promote adhesion of the surface(s) with the solder 80. The adhesion-promoting coating 89 may include, for example, a titanate (such as, for example, Tyzor 131 available from DuPont), a zirconate (such as, for example, Tyzor 217 available from DuPont), a silane (such as, for example, SIB1824 and SIB1821 available from Gelest), or a thin film metal such as, for example, nickel, stainless steel, aluminum, and / or indium.

[0042] Furthermore, prior to applying the solder 80, the first surface 85 and / or the second surface 87 may be prepared by stripping organic materials (such as the oxide layer discussed above) using a detergent or chemical application. This may be in addition to the ultrasonic application of the ultrasonic heater 90, as discussed above. Additionally or alternatively, prior to applying the solder 80, the first surface 85 and / or the second surface 87 may be cleaned of contaminants by applying a mild acid or by using ultraviolet (UV) ozone cleaning techniques.

[0043] A process 100 for forming the optical assembly 10 is shown in Figure 6. The process 100 includes, in step 110, attaching one or more connectors 40 to the optical element 20. As discussed above and shown in Figure 7, the connectors 40 may be attached to the side 25 of the optical element 20 during step 110. Note that Figure 7 shows an embodiment in which all three connectors 40 have the same configuration, and connector 40' has a different configuration.

[0044] Attaching each connector 40 to the optical element 20 during step 110 may include applying solder 80 to the second end 54 of each connector 40 and then heating the solder 80 using an ultrasonic heater 90, as discussed above. Thus, the ultrasonic heater 90 may apply ultrasonic waves to the solder 80. Additionally, the solder 80 may be preheated prior to ultrasonic application. The connector 40 with the attached solder joints is then attached to the optical element 20 such that the solder 80 contacts both the connector 40 and the optical element 20. The connector 40 and the optical element 20 may be held in a specific, precise position relative to one another (such as with an alignment device 200, as discussed below) when attaching the connector 40 with the attached solder joints to the optical element 20. In an embodiment, as shown in FIG. 7 , the solder 80 is applied to the side 25 of the optical element 20. However, as discussed above, it is also contemplated that one or more connectors 40 may be attached to other surfaces of the optical element 20. Once the solder 80 contacts both the connector 40 and the optical element 20 and the ultrasonic application is terminated, the solder 80 solidifies and hardens to form the solder joint 70 (e.g., first solder joint 72). As discussed above, the cavitation process (as induced by the ultrasonic application) causes the optical element 20 and the connector 40 to bond and attach together via the solder joint 70.

[0045] In some embodiments, additional heat may be applied once the solder 80 is in contact with both the connector 40 and the optical element 20. This additional heat may be applied to slow the solidification of the solder 80. Such may provide additional time to further align the connector 40 and the optical element 20 before they are joined and relatively fixed by the solidification and hardening of the solder 80.

[0046] Referring again to process 100, in step 120, optical element 20, with one or more connectors 40 attached, is positioned within the ring-like structure of mount 30. Thus, optical element 20 is positioned within the interior opening of mount 30 formed by inner diameter 34 (as shown in FIG. 1 ). Furthermore, an alignment device 200, such as that shown in FIG. 8 , may be used to align optical element 20 relative to mount 30. FIG. 8 shows a top view of optical element 20 secured and bonded to connectors 40. However, in FIG. 8 , connectors 40 have not yet been secured to mount 30. Alignment device 200 is used to properly position and align optical element 20 relative to mount 30 prior to securing these components together via solder joints 70.

[0047] In some embodiments, the alignment device 200 moves the optical element 20 relative to the mount 30, while the mount 30 is held stationary during the positioning and alignment process. Thus, the optical element 20 can be oriented in various directions relative to the mount 30 during the positioning and alignment process. The optical element 20 can move horizontally (e.g., left and right) and vertically (e.g., up and down), and the optical element 20 can be tilted at an angle relative to the mount 30 to achieve the desired positioning and alignment with the mount 30. In other embodiments, the mount 30 moves relative to the optical element 20, while the optical element 20 is held stationary during the positioning and alignment process. Thus, the mount 30 can move horizontally and vertically and can be tilted at an angle relative to the optical element 20. In yet some other embodiments, both the optical element 20 and the mount 30 move during the positioning and alignment process.

[0048] It should be noted that alignment device 200 may be attached to holes 36 on mount 30 to move and position mount 30 during the positioning and alignment process. Additionally, a gap 220 may be disposed between optical element 20 and mount 30 during the positioning and alignment process of these components. Gap 220 may remain even after optical element 20 is secured to mount 30 via solder joints 70. Thus, when fully assembled into optical assembly 10, optical element 20 and mount 30 may still be separated by gap 220. In embodiments, gap 220 is between about 0.20 mm and about 2.00 mm, or between about 0.25 mm and about 1.75 mm, or between about 0.50 mm and about 1.50 mm, or between about 0.75 mm and about 1.25 mm, or between about 1.00 mm and about 1.50 mm, or between about 0.50 mm and about 1.00 mm.

[0049] In some embodiments, as described above, alignment device 200 may also be used to align the relative positions of connector 40 and optical element 20 when securing these components together via solder joint 70. However, it is contemplated that another device other than alignment device 200 may align the relative positions of connector 40 and optical element 20.

[0050] 3A and 3B , during the positioning and alignment process of the optical element 20 and the mount 30, the connectors 40 may each be disposed in a well 38 of the mount 30. In particular, at least a portion of the arm 50 (including at least an intermediate portion of the arm 50 between the first end 52 and the second end 54) is positioned within the well 38 to facilitate movement of the optical element 20 and the mount 30 relative to one another. The well 38 provides clearance for the connector 40 during the positioning and alignment process of the optical element 20 and the mount 30.

[0051] Also, as shown in Figures 3A and 3B, during the positioning and alignment process of the optical element 20 and the mount 30, the retainer 60 of the connector 40 is disposed within the recess 39 and the first end 52 of the arm 50 is disposed within the passage 37.

[0052] Once the optical element 20 and mount 30 are properly positioned and aligned, the connector 40 may be secured to the mount 30 via the solder joint 70 (e.g., second solder joint 74), as shown in step 130 of process 100. Note that during this connection, the optical element 20 and / or mount 30 continue to be held in the desired positioning and alignment via the alignment device 220. Furthermore, during this connection, the connector 40 is already secured to the optical element 20. Attaching each connector 40 to the mount 30 during step 130 may include applying solder 80 to the horizontal and vertical openings 62, 64 of each retainer 60, as discussed above, and then heating the solder 80 using an ultrasonic heater 90. The connector 40, with the attached solder joint, is then attached to the bottom surface 33 of the recess 39 of the mount 30 such that the solder 80 contacts both the connector 40 and the bottom surface 33. Once connector 40 is attached to mount 30 via solder 80, solder 80 solidifies and hardens to form solder joint 70 (eg, second solder joint 74).

[0053] However, it should also be noted that the connector 40 may be attached to the mount 30 via a ceramic-based or polymer-based attachment instead of the second solder joint 74. When using such a ceramic-based or polymer-based attachment, ultrasonic application from the ultrasonic heater 90 is not required.

[0054] The optical assembly 10 may be formed after the attachment of the connector 40 to the mount 30 (and the attachment of the optical element 20 to the mount 30). However, it is contemplated that the process 100 may first attach and secure the connector 40 to the mount 30 prior to attachment to the optical element 20. Furthermore, in still some other embodiments, the connector 40 may be secured and attached to both the mount 30 and the optical element 20 simultaneously.

[0055] As shown in step 140 of process 100, after connector 40 is secured to mount 30, a filler material may be disposed within well 38 of mount 30 to firmly position connector 40 relative to mount 30. Thus, the filler material bonds to both well 38 and connector 40 (specifically, arms 50) to anchor connector 40. Once the filler material hardens, connector 40 may not be able to move independently of mount 30. Thus, connector 40 is firmly anchored to mount 30. Exemplary filler materials include, for example, inorganic materials such as glass, sand, or metal, or polymeric materials.

[0056] It is also contemplated that in some embodiments, no such filler material is added to well 39 (or mount 30 does not even include such a well). Instead, solder joint 70 may provide the only attachment between connector 40 and mount 30. Such allows for some flexibility of connector 40, and therefore some relative movement between optical element 20 and mount 30.

[0057] It should be noted that in conventional assemblies utilizing polymer joints to fasten the optical element to the mount, the polymer joints can deteriorate or become contaminated over time. Therefore, the joints must be removed and replaced after a certain period of time. Therefore, the optical element and mount could not be securely anchored to one another (as with the filler material disclosed above). Instead, a more temporary, less permanent attachment is required due to the unstable nature of the polymer joint. In contrast to conventional assemblies, the embodiments disclosed herein do not utilize polymer joints to secure the optical element 20 in the mount 30 via the connector 40. Instead, as discussed above, the soldered joint 70 creates a strong, polymer-free joint between these components. Due to the polymer-free aspect of the joint 70, the components can be more permanently secured together via the filler material, thus creating a very stable and sturdy assembly.

[0058] 9A and 9B illustrate an embodiment of a solder joint 70 formed between a glass connector 40 and a side surface 25 of a glass optical element 20. In the embodiment of FIGS. 9A and 9B, a solder material was placed on the surface of the glass connector, and a solder material was placed on the surface of the glass optical element. The solder material was then heated by an ultrasonic heater operating at an oscillation frequency of 65 kHz. The tip of the ultrasonic heater was set to 165°C. Next, the glass connector and the glass optical element were aligned using an alignment device, and the two solder materials were brought into contact. The combined solder materials were then preheated by a hot plate operating at a temperature of 140°C. Finally, the ultrasonic heater applied an ultrasonic wave to the combined solder materials, while the ultrasonic heater was operated at an oscillation frequency of 65 kHz and the tip of the ultrasonic heater was set to 165°C. The ultrasonic wave application was then terminated, and the solder was solidified within the soldered joint.

[0059] Unless otherwise indicated, it is contemplated that any feature of any embodiment may be used in any other embodiment unless incompatible. Optical elements that may be employed include lenses, mirrors, and prisms.

[0060] The described embodiments are preferred and / or illustrative, but not limiting, and various modifications are contemplated within the scope and spirit of the appended claims.

Claims

1. 1. A method of connecting an optical element to a mount, the method comprising: attaching the connector to the optical element with a first solder and heating the first solder with an ultrasonic heater to form a first soldered joint between the connector and the optical element; aligning the optical element within an inner opening of a mount; and attaching the connector to the mount using a second joint; The method, wherein the first solder joint is a polymer-free joint.

2. The method of claim 1 , further comprising applying an oscillation frequency of about 10 kHz to about 100 kHz with the ultrasonic heater.

3. The method of claim 1 or 2, further comprising aligning the optical element within the inner opening of the mount using an alignment device.

4. The method of claim 3 , wherein the alignment device moves the optical element relative to the mount to align the optical element with the mount.

5. 5. The method of claim 1, wherein the method comprises forming the first soldered joint between the connector and the optical element before forming the second joint between the connector and the mount.

6. The method of any one of claims 1 to 5, further comprising positioning the connector within a well in the mount.

7. The method of claim 6 , further comprising filling the well with a filler material to securely fasten the connector to the mount.

8. The method according to any one of claims 1 to 7, wherein the optical element is securely fixed to the mount via the connector.

9. 9. The method of claim 1, wherein the first solder joint comprises one or more of tin (Sn), silver (Ag), copper (Cu), titanium (Ti), cerium (Ce), and gallium (Ga).

10. The method of any one of claims 1 to 9, wherein the second joint is a soldered joint that is a polymer-free joint.

11. 11. The method of claim 10, wherein the second solder joint comprises one or more of tin (Sn), silver (Ag), copper (Cu), titanium (Ti), cerium (Ce), and gallium (Ga).

12. The method according to any one of claims 1 to 11, wherein the optical element is a lens.

13. The method according to any one of claims 1 to 12, wherein the optical element comprises glass and the connector is made of metal and / or glass.

14. The method of any one of claims 1 to 13, wherein the first solder joint between the connector and the optical element is capable of withstanding a pressure load of about 500 psi or more.

15. 1. An optical assembly comprising: Mount and an optical element disposed within the inner opening of the mount; one or more connectors, each connector attached to the optical element via a solder joint, the solder joint being a polymer-free joint constructed from one or more metal alloys.

16. 16. The optical assembly of claim 15, wherein the mount is a ring-shaped member having an inner diameter and an outer diameter, the inner diameter forming the interior opening of the mount.

17. 17. The optical assembly of claim 15 or 16, wherein the optical element comprises a top surface, a bottom surface, and a side surface, and the solder joint is attached directly to the side surface of the optical element.

18. 18. The optical assembly of claim 15, wherein the one or more metal alloys comprise one or more of tin (Sn), silver (Ag), copper (Cu), titanium (Ti), cerium (Ce), and gallium (Ga).

19. The optical assembly of any one of claims 15 to 18, wherein the soldered joint between the connector and the optical element is capable of withstanding a pressure load of about 500 psi or more.

20. An optical assembly according to any one of claims 15 to 19, wherein the connector comprises a cantilever arm.

21. 21. The optical assembly of claim 20, wherein the solder joint is connected to an end of the cantilever arm.

22. 22. The optical assembly of claim 15, wherein the soldered joint comprises a first soldered joint, and the optical assembly further comprises a second soldered joint between the connector and the mount.

23. 23. The optical assembly of claim 15, wherein the connector is made of glass, the optical element is made of glass, and the mount is made of metal.

24. An optical assembly according to any one of claims 15 to 23, further comprising a gap between the optical element and the mount.

25. 25. The optical assembly of claim 24, wherein the gap has a length of about 0.20 mm to about 2.00 mm.

26. An optical assembly according to any one of claims 15 to 25, wherein the optical element is a lens.

27. 27. The assembly of any one of claims 15 to 26, wherein the optical element comprises glass and the connector is constructed from metal and / or glass.

Images