Low-tension optical bench with thermal decoupling

Abstract

The present invention relates to a device for arranging optical components in a thermally decoupled housing (LH), in particular an optical bench (OB) which is suspended with low tension, is thermally decoupled from a laser housing, and is suitable for mobile and satellite-based applications for example in quantum information technology. A device according to the invention for arranging optical components in a housing (LH) comprises a housing; an optical bench (OB) formed monolithically from a rigid material with high thermal conductivity and yield strength; at least two spring elements (SE), acting in the plane of the optical bench (OB), at the outer edges of the optical bench (OB), wherein the optical bench (OB) is fastened to pedestal elements (PE) of the housing (LH) only via the spring elements (SE) and the optical bench (OB) is retained in the housing (LH) in a self-supporting manner via the pedestal elements (PE); clamping bars (CB) beneath the spring elements (SE); thermal insulators (TI) beneath the clamping bars (CB), wherein the clamping bars (CB) rest at least in part on the thermal insulators (TI) and the clamping bars (CB) can be supported stably thereby with respect to the pedestal elements (PE) of the housing (LH); and a thermally conductive strip (TS), wherein a first end of the thermally conductive strip (TS) is fastened in a self-supporting region of the optical bench (OB) and a second end of the thermally conductive strip (TS) is fastened between a pedestal element (PE) and a clamping bar (CB) next to a thermal insulator (TI).

Description

[0001] Title Low-strain optical bench with thermal decoupling Description The present invention relates to a device for arranging optical components in a thermally decoupled housing, in particular a low-strain suspended micro-optical bench that is thermally decoupled from a laser housing, which is suitable for mobile and satellite-based applications, for example in quantum information technology and quantum sensing. State of the art For a variety of applications, for example in quantum information technology, quantum sensing, optical clocks, and coherent satellite communications, laser modules are required that can realize and provide an ultra-stable frequency reference with a narrow linewidth. For the operation of laser modules outside of optical laboratories, such asIn field operation for applications in quantum computing, and particularly for use on a satellite platform, the laser modules must meet particularly high technical requirements. The laser modules must, among other things: ^ be small, lightweight, and compact, ^ exhibit high intrinsic mechanical stability, particularly during launch on a space mission, ^ enable temperature control of the opto-mechanical structure, and ^ be able to ensure very high thermal stability of the entire opto-mechanical structure during operation. Since there are currently no suitable laser modules in the state of the art that can meet all of these technical requirements simultaneously, a low-strain (micro)optical bench is required that is thermally decoupled from a housing but coupled to a dynamically controllable environment for temperature stabilization.In the state of the art, temperature-stabilized housing solutions for particularly compact (diode) laser modules are usually designed as butterfly housings (see, for example, Lyakh, Arkadiy, et al. “1.6 W high wall plug efficiency, continuous-wave room temperature quantum cascade laser emitting at 4.6 μm.” Applied Physics Letters 92.11 (2008): 111110.). These usually use an electro-thermal converter (also known as a Peltier element, or thermo-electric cooler, TEC) located within the laser housing and usually supporting the laser chip and associated collimation optics. The TEC generally has an upper ceramic substrate, which can be considered an optical bench (OB) and acts as a support for all active and passive optical components of the laser setup. However, the floor area of ​​the OB is limited to the maximum floor area of ​​the TEC used, which is limited upwards by technical restrictions.In the prior art, a lens is typically used to collimate the output facet of the laser chip. However, this lens is usually not mounted on the upper ceramic substrate of the TEC and is therefore not considered part of the OB and temperature stabilization. A disadvantage of such butterfly packages is their size limitation. The footprint (length x width) of the OB is limited to the maximum size of the TEC used. The footprint of the TEC in such assemblies is typically only approximately 20 x 20 mm. 2 up to 25 x 25 mm 2available to prevent damage during assembly and operation due to thermo-mechanical expansion of the upper (commonly referred to as cold) ceramic substrate relative to the lower (commonly referred to as hot) ceramic substrate and of the lower (hot) ceramic substrate relative to the housing. Furthermore, it should be noted that if the housing is mechanically deformed by external forces, this can have a direct impact on the OB and cause misalignment of the optical components. DE 102022101921 A1 relates to a holding arrangement with a carrier platform to which at least one optical element is fixed, wherein the holding arrangement is intended to ensure improved beam position stability with the least possible effort. US 6,771,437 B1 discloses optical bench assemblies and thermal management techniques that are intended to enable increased stability.CN 115799973 A shows a packaging structure for heat dissipation for a semiconductor laser. Another temperature-stabilized housing solution for compact satellite-compatible (diode) laser modules is disclosed, for example, in Kürbis et al. (Kürbis, Ch. et al. “Extended cavity diode laser master-oscillator-power-amplifier for operation of an iodine frequency reference on a sounding rocket.” Applied Optics 59.2 (2020): 253-262.) (see FIG. 1). It is known that the OB of a satellite-compatible laser module should be mechanically robust and have the lowest possible coefficient of thermal expansion. To avoid thermo-mechanically induced optical misalignment, precise temperature stabilization using a TEC is typically also implemented in satellite-compatible laser systems. In the laser structure shown in FIG. 1, the OB is made of aluminum nitride for mechanical stabilization and is provided with a housing.The OB is firmly connected to the LH using a Kovar (“laser housing” (LH)) using a thermally conductive adhesive (TCA). The OB is thus firmly connected to the LH. All electrical and optical components and the diode laser chip are integrated on top of the ceramic body of the OB. The LH is screwed to a mounting plate (MP; not shown), which also functions as a heat sink. The distance between the LH and the MP is determined by a module spacer (MS), which serves both as mechanical positioning (of the LH to the MP) and as thermal insulation (between the LH and the MP). A TEC is arranged between the LH and the MP (centered under the LH); this TEC is therefore located outside the LH. To improve heat conduction, thermally conductive and flexible thermal pads (MS) can be used.A thermal interface material (TIM) can be placed between the LH and the TEC, as well as between the TEC and the MP. The TEC serves to precisely control the temperature of the OB. For example, the TEC enables heat dissipation and temperature stabilization of the OB if the temperature of the LH or the thermal load on the OB changes. The footprint of the OB of such a laser module can be significantly larger than that of a butterfly package. For example, the OB shown in FIG. 1 has a footprint of typically approximately 30 x 80 mm. 2 Other laser modules of this type also have OBs with an area of ​​approximately 60 x 95 mm 2However, even with this type of housing solution, mechanical deformation of the LH due to external forces directly affects the OB. This can lead to misalignment of the optical components. Furthermore, a temperature change in the LH also directly affects the temperature of the OB, causing thermal expansion, which can lead to a shift in the laser frequency. In addition, relatively large shear stresses can occur at the OB during strong temperature fluctuations.if the thermal expansion coefficients of the LH and the OB do not match. Therefore, the OB can be stretched and bent, and this in turn can lead to optical misalignment. Finally, the temperature control of the OB by the TEC below the LH requires the stabilization of a non-negligible total thermal mass by the material volume of the LH. In addition, the TEC offers only a narrow control bandwidth (slow temperature control) due to the relatively large thermal resistance of the control loop and the relatively large thermal resistance along the heat flow path via TIM, TCA, and LH. Disclosure of the Invention It is therefore an object of the present invention to provide a low-stress optical bench with good thermal coupling to the environment, which avoids or at least significantly reduces the disadvantages of the prior art. In particular, a low-stress suspended,A micro-optical bench is provided that is thermally well decoupled from a housing and is suitable for mobile and satellite-based applications, for example in quantum information technology and quantum sensor technology. These objects are achieved according to the invention by the features of the independent patent claim. Expedient embodiments of the invention are contained in the associated dependent claims. The features listed individually in the patent claims can be combined with one another in a technologically expedient manner and can be supplemented by explanatory facts from the description and / or details from the figures, whereby further embodiments of the invention are shown. A device according to the invention for arranging optical components in a housing comprises a housing; an optical bench,Monolithically formed from a rigid material with high thermal conductivity and yield strength; at least two spring elements acting in the plane of the optical bench on the outer edges of the optical bench, wherein the optical bench is fastened to the base elements of the housing exclusively via the spring elements and the optical bench is held in the housing in a self-supporting manner via the base elements; Clamping rails below the spring elements; Thermal insulators below the clamping rails, wherein the clamping rails rest at least partially on the thermal insulators (also referred to as thermal insulators) and the clamping rails are stably supported by these against the base elements of the housing; and a thermally conductive strip,wherein a first end of the heat-conducting tape is fixed to a cantilevered region of the optical bench, and a second end of the heat-conducting tape is fixed between a base element and a clamping rail next to a heat insulator. The housing can, in particular, be a laser housing for accommodating a (diode) laser array on the optical bench. However, the present invention is not limited to such applications and can, for example, also relate to a detector housing for accommodating a pure detector array on the optical bench. The housing can, for example, be made of stainless steel, Kovar, or aluminum. The material of the optical bench should be rigid, i.e., have the highest possible elastic modulus E. Preferably, the material has an elastic modulus E of over 70 GPa, more preferably over 100 GPa, even more preferably over 200 GPa. The thermal conductivity κ should also be as high as possible.Preferred values ​​are above 75 W / (m·K), more preferably above 150 W / (m·K), and even more preferably above 200 W / (m·K). The yield strength Re (English: "yield strength") denotes the mechanical stress up to which a material is elastically deformable. Therefore, this value should also be as high as possible. For technical materials, the more precisely determined so-called 0.2% yield strength (also known as elastic limit Rp0.2) is usually specified instead of the yield strength. Preferred values ​​for the 0.2% yield strength are above 200 MPa, more preferably above 300 MPa, and even more preferably above 500 MPa. A particularly high yield strength (or 0.2% yield strength) is preferred,Because the material of the optical bench can be used to mechanically decouple the optical bench from the environment, and plastic deformation under mechanical stress must be avoided at all costs. The optical bench is preferably a micro-optical bench. For the purposes of this application, micro-optical benches are optical benches with a maximum area of ​​up to approximately 10,000 mm. 2 (e.g. an optical bench with an area of ​​60 x 95 mm 2). However, the present invention is not limited to such micro-optical benches. The spring elements on the outer edges of the optical bench are intended to act in particular in the plane of the optical bench. This makes it possible to compensate for different expansions of the optical bench and the housing. In addition, however, the spring elements can also have a spring component acting perpendicular to the plane of the optical bench. In addition to the aforementioned expansion compensation, this also makes it possible to compensate for any bending between the housing and the optical bench. The spring elements can thus be designed to act in different directions. The base elements of the housing have the task of providing support and support points for a self-supporting holder of the optical bench.The base elements should be sufficiently high relative to the housing base to keep both the optical bench and the heat-conducting strips, which are preferably arranged on the underside, away from the housing floor. The invention solves the technical problem of mounting the optical bench in the housing in such a way that mechanical and thermomechanical stress and deformation are kept away from the optical bench while simultaneously enabling good thermal decoupling of the optical bench from the housing. In particular, the optical bench can also be decoupled from mechanical stress from the environment.Mechanical stresses that may arise from the mechanical deformation of the laser housing or from relative thermal expansion or contraction of the optical bench and / or the housing are not transferred to the optical bench because the flexible and mechanically stress-carrying solid structures can absorb all stresses and deformations that occur due to changes in the environment. This means that the material of the housing can also be different from the material of the optical bench. The spring elements are preferably solid-state joint structures arranged in the same plane as the optical bench. The solid-state joint structures can be designed to act in different directions. The solid-state joint structures can preferably act in the plane of the optical bench as well as perpendicular to this plane.For this purpose, the spring elements can comprise narrow webs and tapered areas, through which a substantial mechanical decoupling can be achieved between the self-supporting optical bench and the sections of the individual spring elements that are firmly connected to the base elements of the housing. In particular, stresses occurring between the housing and the optical bench can be absorbed via the spring elements so that they cannot affect the optical bench. Preferably, the spring elements are formed monolithically in the material of the optical bench. This enables a homogeneous formation of the structures and increases their reliability. Alternatively, however, the spring elements can also be formed independently of the optical bench from the same or a different material as the optical bench and connected to it. Connection can be achieved, for example, by soldering, welding, gluing, screwing or a combination thereof.Preferably, the optical bench is made of a Mo. 70 Cu 30 alloy, Kovar or another metallic or ceramic material. The use of Mo 70 Cu 30 alloy is particularly preferred because the material Mo 70 Cu 30 It has the properties of being non-magnetic, low gas content, high thermal conductivity, and a low coefficient of thermal expansion, is suitable for vacuum applications, and is easy to process. Furthermore, it has a coefficient of thermal expansion that is largely consistent with that of GaAs (a material typically used for laser chips). 70 Cu 30 -alloy for forming an optical bench is not yet known in the state of the art. Instead of a particularly preferred mo 70 Cu 30 -alloy, however, a different Mo x Cu 100-x- alloy with x between 50 and 90, more preferably between 60 and 80 can be used. A suitable ceramic material can be, for example, aluminum oxide or aluminum nitride. Preferably, the optical bench is connected to the base elements in the housing via a screw connection, a soldered connection, a welded connection, a clamped connection, an adhesive connection or a combination thereof. In addition to easy detachability of the connection, a screw connection offers the advantage of particular reliability and simplicity. Preferably, the first end of the thermally conductive strip is attached to the optical bench via a soldered connection, a welded connection, an adhesive connection or a clamped connection. To improve heat transfer, a thermally conductive pad can be arranged between the first end of the thermally conductive strip and the optical bench.Preferably, an electro-thermal transducer is arranged between the second end of the heat-conducting strip and the base element. Alternatively or additionally, a resistance heater can also be arranged between the second end of the heat-conducting strip and the base element. For example, in particularly cold environments (Arctic, space), the resistance heater can be used alongside the electro-thermal transducer to heat the optical bench, thus providing a "thermal offset" to provide basic heat even without the need for rapid control via an electro-thermal transducer. However, if rapid temperature control is not required, the resistance heaters can also be used without additional electro-thermal transducers.Preferably, an electro-thermal converter or resistance heater arranged between the second end of the heat-conducting strip and the base element contacts the second end of the heat-conducting strip at its top and / or bottom, directly or via a heat-conducting pad. Fixing can be achieved, for example, by soldering, welding, gluing, clamping, or a combination thereof. An optical bench according to the invention offers significant advantages over the solutions known from the prior art. The optical bench according to the invention can be fastened to the housing using screws. The optical bench can contain, for example, lenses, mirrors, polarization optics (retardation plates, polarizers), electro-optical or acousto-optical modulators, laser chips, gas cells, and / or discrete electronics (temperature sensors, TEC, photodiodes, etc.) as optical components.) to function as a laser, spectroscopy device, beam switching, beam splitting, or beam combining module, laser pulse generation, or a combination thereof. The spring elements can be provided by cutting out some portions of a material used to provide the optical bench to create flexible and resilient mechanical structures (including bends, tapers, and joints). The electrothermal transducers or resistive heaters, the thermal pads, and the thermal insulators can be housed entirely inside the housing and positioned between the optical bench and the housing. Therefore, the heating or cooling of the optical bench can be controlled by the operation of the electrothermal transducers or resistive heaters, and the optical bench and the housing are thermally decoupled from each other.A change in the temperature of the housing therefore does not affect the temperature of the optical bench, since the electro-thermal transducers or resistive heaters, the thermal pads and the thermal insulators between the optical bench and the laser housing make it possible to regulate the temperature of the optical bench independently of the temperature of the housing. Flexible thermal tapes can connect the underside of the optical bench to the electro-thermal transducers or resistive heaters to create specific paths for heat transfer. The thermal tapes can be glued to the optical bench at one end using a thermally conductive adhesive and attached to the electro-thermal transducers or resistive heaters at the other end. The thermal tapes enable thermal contact between the optical bench and the electro-thermal transducers or resistive heaters.Resistance heaters, without creating a strong mechanical coupling between the optical bench and the electrothermal transducers or resistance heaters. Compared to the prior art, the electrothermal transducers or resistance heaters can be arranged significantly closer to the optical bench, thereby reducing the thermal resistance between the housing and the optical bench and enabling improved and accelerated temperature regulation of the optical bench. Compared to prior art devices, the present invention is also significantly more robust against vibrations, mechanical deformations and stresses, as well as against temperature fluctuations, since the optical bench is not rigidly connected to the housing due to the spring elements and is thermally decoupled from the housing due to the specific design of the heat paths.In some embodiments of the present invention, the spring elements can be designed in particular such that they are not flexible in all directions, and their arrangement and properties are selected such that the optical bench assumes a defined position. However, the optical bench should not be freely "floating" in the housing via the spring elements; rather, the spring elements should be adapted accordingly to simply follow deformations of the housing and absorb the resulting mechanical forces and stresses without deforming the optical bench.The present invention can be used, for example, as: ^ an ultrastable clock laser in an optical atomic clock system, ^ a local oscillator for coherent (inter-)satellite communication, ^ a laser system for neutral atom- or ion-based quantum calculations, and ^ a laser system for atom-interferometric inertial navigation or for gravitational gradiometry. The present invention can further be used to implement photonic modules and systems that enable laser beam control, e.g., for pulse generation, beam combining and distribution, and the like. In general, the invention supports the miniaturization of both photonic and electro-optical solutions. Further preferred embodiments of the invention emerge from the features recited in the respective subclaims.The various embodiments of the invention mentioned in this application can be advantageously combined with one another, unless stated otherwise in individual cases. Brief description of the drawings The invention and the technical background are explained in more detail below with reference to the accompanying figures. It should be noted that the invention is not intended to be limited by the exemplary embodiments cited. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and combine them with other components and findings from the present description. They show: Fig. 1 a schematic representation of a device for arranging optical components according to the prior art; Fig. 2 a schematic representation of an embodiment of a device for arranging optical components according to the invention; and Fig.3 shows a schematic representation of the device according to the invention for arranging optical components according to FIG. 2 in cross section. Detailed description of the drawings Figure 1 shows a schematic representation of a device for arranging optical components according to the prior art. The device shown is a housing for compact satellite-compatible (diode) laser modules according to Kürbis (Kürbis, Ch. et al. “Extended cavity diode laser master-oscillator-power-amplifier for operation of an iodine frequency reference on a sounding rocket.” Applied Optics 59.2 (2020): 253-262.), in which the optical bench OB is made of aluminum nitride for mechanical stabilization and is bonded to a housing LH made of Kovar using a thermally conductive adhesive TCA. The optical bench OB is thus firmly connected to the housing LH.All electrical and optical components and the diode laser chip are integrated on top of the ceramic body of the optical bench OB. The housing LH is screwed to a mounting plate (MP; not shown), which also functions as a heat sink. The distance between the housing LH and the mounting plate MP is determined by a module spacer (MS), which serves both for mechanical positioning (of the housing LH on the mounting plate MP) and thermal insulation (between the housing LH and the mounting plate MP). An electro-thermal converter (Peltier element) TEC is arranged between the housing LH and the mounting plate MP (centered under the housing LH); it is thus located outside the housing LH. To improve heat conduction, thermally conductive and flexible thermal pads (MS) can be used."thermal interface material, TIM") between the housing LH and the electro-thermal converter TEC as well as between the electro-thermal converter TEC and the mounting plate MP. The electro-thermal converter TEC serves for the precise temperature control of the optical bench OB, e.g., the electro-thermal converter TEC enables the dissipation of heat and temperature stabilization of the optical bench OB if the temperature of the housing LH or the thermal load of the optical bench OB changes. Figure 2 shows a schematic representation of an embodiment of a device according to the invention for arranging optical components. The device comprises a housing LH (not shown in the illustration); an optical bench OB, monolithically formed from a rigid material with high thermal conductivity and yield strength; at least two in the plane of the optical bench OB (ieagainst the outer edges) on the outer edges of the optical bench OB, wherein the optical bench OB is fastened to base elements PE of the housing LH exclusively via the spring elements SE and the optical bench OB is held in a self-supporting manner via the base elements PE in the housing LH; clamping rails CB below the spring elements SE; heat insulators TI below the clamping rails CB, wherein the clamping rails CB rest at least in sections on the heat insulators TI and the clamping rails CB are stably supported by these with respect to the base elements PE of the housing LH, and a heat conducting strip TS, wherein a first end of the heat conducting strip TS is fixed to a self-supporting area of ​​the optical bench OB and a second end of the heat conducting strip TS is fixed between a base element PE and a clamping rail CB next to a heat insulator TI.The housing LH can, in particular, be a laser housing for accommodating a (diode) laser arrangement on the optical bench OB. However, the present invention is not limited to such applications and can, for example, also relate to a detector housing for accommodating a detector arrangement on the optical bench OB. The spring elements SE are solid-state joint structures arranged in a plane with the optical bench OB. The solid-state joint structures can be designed to act in different directions. The solid-state joint structures can preferably act in the plane of the optical bench OB as well as perpendicular to this plane.For this purpose, the spring elements SE can, as shown, comprise narrow webs (effect in the plane of the optical bench OB) and tapered regions (effect perpendicular to the plane of the optical bench OB), by means of which a substantial mechanical decoupling is achieved between the self-supporting optical bench OB and the sections of the individual spring elements SE that are firmly connected to the base elements PE of the housing LH. In particular, stresses occurring due to different expansion or bending between the housing LH and the optical bench OB can be absorbed via the spring elements SE, so that these stresses cannot affect the optical bench OB. However, the present invention is not limited to the solid-state joint structures shown only as examples in the illustration. In the illustration, the spring elements SE are formed monolithically in the material of the optical bench OB.However, the spring elements SE can also be formed independently of the optical bench OB and made of the same or a different material as the optical bench OB and connected to it. The optical bench OB is preferably made of a Mo. 70 Cu 30-alloy, Kovar or another metallic or ceramic material. The optical bench OB shown is connected to the base elements PE in the housing LH via a screw connection. Alternatively, however, a soldered connection, a welded connection, a clamped connection, an adhesive connection or a combination thereof can also be used. The first end of the heat-conducting strip TS is preferably attached to the optical bench OB via a soldered connection, an adhesive connection, a welded connection or a clamped connection. An electro-thermal converter (Peltier element) TEC is arranged between the second end of the heat-conducting strip TS and the base element PE. Instead of the electro-thermal converter TEC or in addition to it, a resistance heater can also be arranged between the second end of the heat-conducting strip TS and the base element PE.An electrothermal transducer TEC or resistance heater arranged between the second end of the thermally conductive strip TS and the base element PE can contact the second end of the thermally conductive strip TS on its top and / or bottom side directly or via a thermally conductive pad TIM. In particular, the device shown comprises six stainless steel screws SSS for fastening in a housing LH with two base elements PE (the housing is not shown in the illustration), twelve stainless steel washers SSW, six PEEK washers PW made of polyetheretherketone (PEEK), an optical bench OB, four spring elements SE, two clamping rails CB (one clamping rail CB each as a support for two adjacent spring elements SE), six thermal insulators TI made of polyetheretherketone (PEEK), thermally conductive adhesive TCA, four thermal strips TS, thermal thermal pads TIM, and four electrothermal transducers TEC.The assembly of such an exemplary preferred embodiment comprises a combination of gluing, pressing, and screwing between the optical bench OB and the laser housing LH. The optical bench OB is preferably made of a material new for this purpose, consisting of (pure) molybdenum and an (oxygen-free) copper alloy (Mo70Cu30). Alternatively, a ceramic material such as aluminum nitride or another metallic material such as Kovar can be used to manufacture the optical bench OB. However, the ceramic material (aluminum nitride) used by Kürbis et al. is not suitable for the described embodiment of the present invention with screw connections, since its strength makes it unsuitable for screwing. A Mo. 70 Cu 30 -alloy for forming an optical bench is not yet known in the state of the art. Instead of a particularly preferred mo 70 Cu 30-alloy, however, a different Mo x Cu 100-x-alloy with x between 50 and 90, more preferably between 60 and 80 can be used. In the embodiment shown, four spring elements SE acting in the plane of the optical bench OB (i.e. against the outer edges) and perpendicular to this (i.e. with respect to bending upwards or downwards) are arranged at the outer edges of the optical bench OB at the corners of the rectangular optical bench OB. The four spring elements SE each contain a screw hole. In the screw holes there are four stainless steel screws SSS with which the optical bench OB can be firmly connected to a base element PE of the housing LH. However, the optical bench OB is not attached directly to the base elements PE of the housing LH but via two clamping rails CB (arranged parallel on two opposite edges of the optical bench) and four heat insulators TI arranged underneath.The clamping rails CB, which can also be made of Mo70Cu30 or another alloy corresponding to the material of the optical bench OB, are used to clamp all thermal-mechanical components, such as the thermal insulators TI, the thermally conductive strips TS, the thermally conductive pads TIM, and the electro-thermal converters TEC. Each terminal block CB and each thermal insulator TI also contains appropriately arranged screw holes to enable the screw connection between a spring element SE and the corresponding base element PE of the housing LH. The central part of the optical bench OB, on which the optical components are arranged, is suspended inside the housing LH on mechanical flexure hinge structures and does not touch the floor of the housing LH. The flexure hinge structures are aligned and positioned to ensure isostatic support of the optical bench OB relative to the housing LH.The flexible and mechanically stress-absorbing solid-state joint structures shown can ensure isostatic support, especially when the joints are freely rotatable, can bend / deform freely in the intended direction, and are approximately infinitely stiff for any other deformation. With the help of this isostatic or nearly isostatic support, the deformation of the optical bench OB resulting from mechanical deformation of the housing LH or deformation due to thermally induced expansion or contraction of the housing LH or the optical bench OB, or both, can be significantly reduced compared to previous state-of-the-art solutions. The stainless steel screws SSS (including the stainless steel washers SSW) do not have direct contact with the surface of the optical bench OB, but are thermally decoupled by interposed PEEK washers PW.The PEEK washers PW are used to reduce direct heat transfer between the housing LH and the optical bench OB along the stainless steel screws SSS and stainless steel washers SSW. In addition, the PEEK washers SSW provide high mechanical strength. The use of thermal insulators TI prevents direct heat flow between the housing LH and the spring elements SE via the fastening areas of the stainless steel screws SSS, while simultaneously providing vertical space for the central part of the optical bench OB to prevent contact with the bottom of the housing LH. Four thermally conductive strips TS are attached beneath the optical bench OB. A first end of each of the thermally conductive strips TS can be attached to a central, lower part of the optical bench OB using a thermally conductive adhesive TCA.The second end can also be attached to a clamping rail CB using a thermally conductive adhesive TCA. Four electro-thermal transducers TEC are mounted below the second ends of the thermally conductive strips TS and connected to them via optional intermediate thermal pads TIM on the top side of the TEC. The underside of the electro-thermal transducers TEC is connected to the bottom of the housing LH or to the base elements PE arranged therein, whereby a connection can also be made via optional intermediate thermal pads TIM. The thermally conductive strips TS are used to define the path for heat transfer from the optical bench OB to the electro-thermal transducers TEC. The thermal insulators TI prevent or suppress a thermal short circuit between the edges of the optical bench OB, which are supported by the spring elements SE, and the corresponding corners of the housing LH.The TIM thermal pads are preferably used to ensure good thermal conductivity between the TEC electrothermal transducers and the LH housing, as well as between the TEC electrothermal transducers and the TS thermal conduction strips. An additional combination of MS module spacers and MP mounting plates, as in the prior art, is not required, since the TEC electrothermal transducers are arranged within the LH housing in the illustrated embodiment of the invention. The CB clamping rails evenly distribute the forces applied via the stainless steel screws across the assembly consisting of the TEC electrothermal transducers, the TS thermal conduction strips, and the TIM thermal pads, firmly securing them to one another within the LH housing.Furthermore, as shown in the illustration, two additional sets of stainless steel screws SSS and stainless steel washers SSW, PEEK washers PW and thermal insulators in the middle of the two clamping rails CB can be used via additional screw holes in the clamping rails CB. This prevents uneven compression of the clamping rails on the underlying components, which can cause bending and large horizontal displacement (in the event of shock and vibration) of the TEC, thermal strips TS and thermal insulators TIM. Figure 3 shows a schematic representation of the device according to the invention for arranging optical components according to FIG. 2 in cross-section. The individual reference numerals and their respectively assigned features apply accordingly. Like reference numerals belong to the same features. A detailed description of the individual features shown is therefore omitted. Reference is made to the description of FIG. 2.Both the self-supporting structure of the optical bench OB and the spring elements SE resting on the respective base elements PE can be seen at the outer edges of the optical bench OB. Thermal coupling of the optical bench OB with the environment or the housing LH is achieved via thermally conductive strips TS.

[0002] List of reference symbols MS module spacer MP mounting plate TIM thermal interface material TEC thermo-electric cooler LH laser housing TCA thermally conductive adhesive OB optical bench TS thermal strap TI thermal insulator CB clamping bar SSS stainless-steel screw SSW stainless-steel washer PW PEEK washer PE pedestal element SE spring element spring element

Claims

Patent claims 1. Device for arranging optical components in a housing (LH), comprising: a housing; an optical bench (OB), monolithically formed from a rigid material with high thermal conductivity and yield strength; at least two spring elements (SE) acting in the plane of the optical bench (OB) on the outer edges of the optical bench (OB), wherein the optical bench (OB) is fastened to base elements (PE) of the housing (LH) exclusively via the spring elements (SE) and the optical bench (OB) is held in the housing (LH) in a self-supporting manner via the base elements (PE); clamping rails (CB) below the spring elements (SE); heat insulators (TI) below the clamping rails (CB), wherein the clamping rails (CB) rest at least in sections on the heat insulators (TI) and the clamping rails (CB) can be stably supported by these against the base elements (PE) of the housing (LH);and a heat-conducting strip (TS), wherein a first end of the heat-conducting strip (TS) is fixed to a self-supporting region of the optical bench (OB) and a second end of the heat-conducting strip (TS) is fixed between a base element (PE) and a clamping rail (CB) next to a heat insulator (TI).

2. Device according to claim 1, wherein the spring elements (SE) are solid-state joint structures arranged in a plane with the optical bench (OB).

3. Device according to claim 1 or 2, wherein the spring elements (SE) are formed monolithically in the material of the optical bench (OB).

4. Device according to claim 1 or 2, wherein the spring elements (SE) are formed independently of the optical bench (OB) from the same or a different material as the optical bench (OB) and are connected to it.

5. Device according to one of the preceding claims, wherein the optical bench (OB) is made of a Mo; 70 Cu 30alloy, Kovar, or another metallic or ceramic material. 1 6. Device according to one of the preceding claims, wherein the optical bench (OB) is connected to the base elements (PE) in the housing (LH) via a screw connection, a soldered connection, a welded connection, a clamped connection, or an adhesive connection.

7. Device according to one of the preceding claims, wherein the first end of the heat-conducting strip (TS) is attached to the optical bench (OB) via a soldered connection, a welded connection, an adhesive connection, or a clamped connection.

8. Device according to one of the preceding claims, wherein an electrothermal converter (TEC) is arranged between the second end of the heat-conducting strip (TS) and the base element (PE).

9. Device according to one of the preceding claims, wherein a resistance heater is arranged between the second end of the heat-conducting strip (TS) and the base element (PE). 10.Device according to one of the preceding claims, wherein an electrothermal converter (TEC) or resistance heater arranged between the second end of the thermally conductive strip (TS) and the base element (PE) contacts the second end of the thermally conductive strip (TS) at its top and / or bottom side directly or via a thermally conductive pad (TIM). FIG. 2

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