JP2017017058A - Lid body for optical device and optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lid body for an optical device that has reduced a stress to be applied to a glass plate.SOLUTION: A lid body for an optical device comprises: a frame body 32 that includes an upper face and a lower face each having rectangular outer periphery and inner periphery in a perspective view of the upper face; and a glass plate 33 that includes a rectangular lower face and has an outer peripheral part of the lower face joined to the upper face of the frame body 32. The upper face of the frame body 32 is an inclined surface inclined downward from one side 321 to the other side 322 of a pair of corners located respectively on one diagonal line.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a lid for an optical device for sealing an optical element such as a mirror device used in a projector or the like, and an optical device.

  In general, for example, in an optical apparatus having an optical element such as a mirror device, high airtightness is required in order to stably operate a minute mirror. Therefore, a lid for an optical device in which the lower surface of a glass plate is bonded to the upper surface of a rectangular frame such as a rectangular shape is used.

  As a material for forming the frame, a material having a relatively high rigidity such as a ceramic sintered body may be used in consideration of suppressing deformation such as elastic deformation of the frame. In general, the outer peripheral portion of the lower surface of the glass plate is bonded to the upper surface of the frame body by a bonding material such as a glass bonding material on the planar upper surface of the frame body. The optical device lid is bonded onto the substrate on which the optical element is mounted by a bonding method such as bonding using a bonding material or a welding method, and the optical element is sealed to manufacture an optical device. In this case, a member such as a metal frame is disposed between the frame and the substrate as necessary.

JP 2003-282754 A

  However, the conventional structure as described in Patent Document 1, for example, has the following problems with respect to the characteristics of the optical device lid and the optical device. That is, since the frame body has a structure that maintains the airtightness by compressing the glass plate from the side, stress tends to remain inside the glass plate. Further, for example, when the metal frame is deformed by sealing by seam weld bonding as a welding method, a stress is directly applied to the glass plate, and the stress tends to remain inside the glass plate. And in the part to which the stress was added, the phenomenon of birefringence in which the refractive index deviates from the refractive index of the original glass plate tends to occur. As described above, when birefringence occurs in the glass plate, the diffraction angle of the image transmitted through the glass plate varies depending on the part, and thus there is a problem that distortion is likely to occur in the projected image.

  Further, in the conventional lid for an optical device and the optical device, there is the following possibility regarding the above birefringence. That is, in order to avoid the so-called ghost phenomenon in which the light reflected on the surface of the optical element is reflected again on the glass plate and enters the optical element to deteriorate the image, the surface of the optical element and the surface of the glass plate (the lower surface facing the optical element) May be a non-parallel structure. In the case of this structure, in order to incline the upper surface on which the glass plate of the frame is mounted, the frame has a high (thick) portion and a low (thin) portion. Since the rigidity of the portion having a relatively small thickness is lowered, the stress is easily concentrated and the birefringence is increased. For this reason, it may be difficult to reduce the thickness of the device.

The lid for an optical device according to one aspect of the present invention has a frame body having an upper surface and a lower surface each having an outer periphery and an inner periphery that are rectangular when viewed from above, and a rectangular lower surface. The outer peripheral part has the glass plate joined to the said upper surface of the said frame. The upper surface of the frame is an inclined surface that is inclined downward from one to the other of a pair of corners located on one diagonal line.

  An optical device according to one aspect of the present invention has an optical device lid having the above-described configuration and an upper surface including a mounting portion for an optical element, and the optical device lid surrounds the mounting portion on the upper surface. A substrate on which the body is disposed, and an optical element mounted on the mounting portion.

  According to the lid for an optical device according to one aspect of the present invention, since it has the above-described configuration, it is difficult to apply the stress such as the compressive stress as described above to the glass plate, and the residual stress is effective. Reduced. Therefore, it is possible to provide a lid for an optical device that can reduce the possibility of birefringence due to residual stress and can easily form an optical device having excellent characteristics such as an image.

  The reduction of the stress applied to the glass plate is as follows. That is, since the upper surface of the frame body is inclined as described above, the distance between the outer periphery of the upper surface of the frame body and the outer periphery of the glass plate is the portion where the upper surface of the frame body is the lowest (the thinnest portion). The other corner is larger than the other corner. In other words, the distance from the outer periphery of the frame to the glass plate is larger at the portion where the stress generated in the frame is larger. Therefore, it is suppressed that stress is added to a glass plate. Therefore, birefringence in the glass plate is effectively suppressed.

  Moreover, according to the optical device according to one aspect of the present invention, since the optical device lid having the above-described configuration is provided, it is possible to provide an optical device in which problems such as birefringence are effectively suppressed. it can.

It is a perspective view which shows the cover body for optical devices of embodiment of this invention. (A) is a top view of the lid | cover for optical apparatuses shown in FIG. 1, (b) is sectional drawing in the AA of (a), (c) is in the BB line of (a). It is sectional drawing. It is the top view seen from the direction perpendicular | vertical to the upper surface of the frame of the cover for optical devices shown in FIG. It is a perspective view which shows the optical apparatus of embodiment of this invention. (A) is a top view of the optical apparatus shown in FIG. 4, (b) is sectional drawing in the AA of (a). 2A is a top view showing a first modification of FIG. 2A, FIG. 2B is a sectional view taken along line AA in FIG. 2A, and FIG. It is sectional drawing in a line. FIG. 2A is a top view showing a second modification of FIG. 2A, FIG. 2B is a cross-sectional view taken along the line AA in FIG. 2A, and FIG. It is sectional drawing in a line.

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. Note that the drawings used in the following description are schematic, and the dimensional ratios and the like on the drawings do not necessarily match the actual ones. For convenience of explanation, the optical device defines an orthogonal coordinate system xyz and uses the word “upper surface (front surface)” or “lower surface” with the positive side in the z direction as the upper side.

  In the description of the embodiments and the like, the same or similar configurations as those already described may be denoted by the same reference numerals and description thereof may be omitted.

An optical device lid and an optical device according to an embodiment of the present invention will be described with reference to FIGS. The optical device lid of the embodiment is shown in FIGS. 1 to 3, and the optical device including the optical device lid is shown in FIGS. In this embodiment, the optical element 2 is mounted on the optical device substrate 1, and the optical device lid 3 is bonded onto the optical device substrate 1 to seal the optical element 2. Thus, the optical device 4 according to the embodiment of the present invention is basically formed.

  As shown in FIGS. 1 and 2, the optical device lid 3 according to the embodiment includes a frame 32 in which a metal frame 31 is bonded to the outer periphery of the lower surface, and a glass bonding material 34 on the upper surface of the frame 32. It has the glass plate 33 joined. The frame body 32 and the metal frame 31 have a frame shape (rectangular frame shape) having a rectangular outer periphery and inner periphery when viewed from above (when viewed from a direction perpendicular to the upper surface of the metal frame 31). The glass plate 33 has a rectangular flat plate shape.

  As shown in FIG. 2, the metal frame 31 has a first opening 31a penetrating in the thickness direction, and has a frame-like portion 31b surrounding the first opening 31a. The frame 32 corresponds to the first opening 31a, and has a second opening 32a that is surrounded by side walls 32c on all sides. A glass bonding material 34 is formed by the outer peripheral portion of the lower main surface (lower surface) of the glass plate 33 and the inner peripheral portion of the upper surface of the frame 32 so as to close the first opening 31a and the second opening 32a. Are joined together.

  The optical device substrate 1 includes a substrate 11, a wiring conductor (not shown) provided on the upper surface, lower surface, or inside of the substrate 11, and a bonding metal ring 12 provided on the upper surface of the substrate 11. . The board | substrate 11 has the recessed part 11a on the upper surface. The recess 11a becomes a mounting area for the optical element 2.

  The substrate 11 is made of, for example, a ceramic material (ceramic sintered body). When the substrate 11 is made of a ceramic material, it is integrally formed by firing. As shown in FIG. 5, the optical element 2 is mounted on the bottom of the recess 11a and mounted on the optical device substrate 1 using a wire bonding method. Moreover, although the board | substrate 11 has provided the mounting area | region in the recessed part 11a, it is not restricted to this. The board | substrate 11 may provide a mounting area | region in the flat part of a center area | region, without forming a recessed part.

When the substrate 11 is made of, for example, a ceramic material, an example thereof is an aluminum oxide (alumina: Al ₂ O ₃ ) sintered body or an aluminum nitride (AlN) sintered body. On the substrate 11, the above-described wiring conductor, bonding metallization layer (not shown), and the like are formed.

If the substrate 11 is made of, for example, an aluminum oxide sintered body, first, raw material powder of alumina (Al ₂ O ₃ ) and silica (SiO ₂ ), calcia (CaO), magnesia (MgO) or the like is used. A suitable organic solvent and a solvent are added and mixed to form a slurry, which is formed into a sheet using a known doctor blade method or calender roll method or the like to obtain a ceramic green sheet (hereinafter also referred to as a green sheet).

  Next, a conductor paste layer to be a wiring conductor and a bonding metallization layer is formed to a thickness of about 10 (μm) to 20 (μm) at a predetermined position of the green sheet using a screen printing method or the like.

  The conductive paste is produced by kneading a metal powder having a high melting point such as tungsten (W), molybdenum (Mo), or molybdenum-manganese (Mo-Mn) alloy with an appropriate resin binder and solvent.

Next, a through-hole that becomes the recess 11a is formed at a predetermined position of the green sheet by using an appropriate punching process, and if necessary, these green sheets are stacked and pressure-bonded to produce a laminated body. Is fired at a high temperature of about 1600 (° C.) to produce a mother substrate in a multi-piece state. In this mother substrate, a plurality of substrate regions each serving as the substrate 11 are arranged in a vertical and horizontal arrangement or the like.

  Next, in the above-described mother board, a plating layer is provided on a metallized layer such as a wiring conductor and a bonding metallized layer as necessary. Note that the plating layer is formed of a metal material such as nickel, for example. The mother board is provided with a brazing material using, for example, a silver-copper eutectic alloy in a predetermined shape on the metallization layer for bonding using an assembly jig. And the metal ring 12 for joining is arrange | positioned on the brazing material of a silver copper eutectic alloy, for example. Further, the bonding metal ring 12 is produced, for example, by forming a FeNi29Co17 alloy into a predetermined shape using a known press working method or the like.

  In this case, for example, by maintaining the temperature exceeding the melting point of the brazing material in a reducing atmosphere, the joining metallized layer (not shown) on the substrate 11 and the joining metal ring 12 are joined via the brazing material. Has been. Further, if necessary, a nickel plating layer or a gold plating layer is formed on the bonding metal ring 12 or the like by using a plating method, and the mother substrate is divided into individual pieces, whereby the optical device base 1 and Become.

  The joining metal ring 12 is used for seam weld joining to the metal frame 31 of the optical device lid 3. The optical device lid 3 (the lower surface of the metal frame 31) is bonded onto the bonding metal ring 12 of the optical device substrate 1 via the bonding material 35, whereby the optical element 2 is hermetically sealed.

  When the substrate 11 is made of an aluminum oxide sintered body, since the substrate 11 has high mechanical strength, warpage or the like hardly occurs and the optical element 2 has an appropriate thermal conductivity. It becomes easy to dissipate the generated heat to the outside. Thus, when the substrate 11 is an aluminum oxide sintered body, it is excellent in terms of mechanical strength, thermal conductivity, or cost.

  The optical element 2 is, for example, a mirror device. For example, the optical element 2 reflects light incident on the mirror device to project an image or the like on a screen. The optical element 2 may be a light emitting element such as a light emitting diode.

  As described above, for example, in the example illustrated in FIGS. 1 and 2, the optical device lid 3 includes the metal frame 31, the frame 32 provided on the metal frame 31, and the glass bonding material 34 on the frame 32. And a glass plate 33 joined through the glass plate 33. The metal frame 31 and the frame body 32 are joined via a joining material 35.

  The metal frame 31 has a first opening 31a penetrating the upper surface (one main surface) and the lower surface (the other main surface), and the first opening 31a is surrounded by a frame-shaped portion 31b. Yes. Thus, the metal frame 31 has a rectangular shape in a top view, penetrates in the thickness direction, the first opening 31a is provided in the central portion, and the first opening 31a is the frame-shaped portion 31b. being surrounded. The first opening 31a has, for example, a rectangular shape. The metal frame 31 has a side length of, for example, 10 (mm) to 30 (mm), and the first opening 31a has a side length of, for example, 5 (mm) to It is opened at 20 (mm).

  Further, the metal frame 31 may have a thermal expansion coefficient similar to that of the frame body 32, the glass plate 33, and the substrate 11 joined to the upper surface of the frame-shaped portion 31b. The substrate 11 is made of a ceramic material such as an aluminum nitride sintered body or an alumina sintered body, which has excellent thermal conductivity and is excellent in terms of heat dissipation. Therefore, the metal frame 31 may have a thermal expansion coefficient similar to that of the aluminum nitride sintered body or the alumina sintered body.

For example, 42 alloy (thermal expansion coefficient is about 5.0 (× 10 ⁻⁶ / ° C.)) or FeNi29Co17 alloy (thermal expansion coefficient is about 4.8 (× 10 ⁻⁶ / ° C.)) is an aluminum nitride sintered body. Thermal expansion coefficient (linear thermal expansion coefficient is about 4.6 (× 10 ⁻⁶ / ° C.)) or thermal expansion coefficient of alumina sintered body (linear thermal expansion coefficient is about 7.2 (× 10 ⁻⁶ / ° C.) The metal frame 31 may be made of 42 alloy or FeNi29Co17 alloy.

  Moreover, the metal frame 31 can have the 1st opening part 31a in the area | region including a center part, for example by processing a metal plate using an etching method or a press work method.

  As shown in FIG. 1, the frame body 32 is surrounded by four side walls 32 c and has a second opening 32 a corresponding to the first opening 31 a of the metal frame 31. The outer shape is rectangular when viewed from above. The frame 32 is made of a material having higher rigidity than the glass plate 33, for example, the same ceramic material as the substrate 11. Further, the upper surface of the frame 32 has a rectangular shape with a side length of, for example, 8 (mm) to 27 (mm) when viewed from above (when viewed from a direction perpendicular to the upper surface of the substrate 11). A frame having an outer periphery. The inner periphery of the upper surface of the frame 32 is, for example, a rectangular shape having four sides parallel to the four sides of the outer periphery. Further, the lower surface of the frame body 32 has a rectangular frame shape having the same shape and dimensions as the upper surface in a top perspective view. That is, the frame 32 has an upper surface and a lower surface whose outer periphery and inner periphery are rectangular in top surface perspective. In other words, when viewed through in the z-axis direction, the upper surface and the lower surface of the frame 32 are both rectangular frame shapes.

The frame 32 is made of, for example, aluminum oxide (alumina: Al ₂ O ₃ , alumina Young's modulus: 370 (Gpa)) sintered body or aluminum nitride (AlN, aluminum nitride Young's modulus: 320 (Gpa)) sintered Thus, when a material having higher rigidity than the glass plate 33 (Young's modulus of D263 glass: 72 (Gpa)) is used, the stress applied to the glass plate 33 can be reduced.

  Further, the frame body 32 can be produced, for example, by forming a green sheet mainly composed of a ceramic material such as aluminum oxide or aluminum nitride into a predetermined shape and firing the same as the substrate 11. Alternatively, an unfired molded body having a predetermined shape to be the frame body 32 may be produced and fired by powder press molding using a mold.

  In the frame body 32, the lower surface of the side wall 32 c is joined to the frame-shaped portion 31 b of the metal frame 31. That is, the frame body 32 is joined to the frame-shaped portion 31 b on the upper surface of the metal frame 31 so that the second opening portion 32 a corresponds to the first opening portion 31 a of the metal frame 31.

  As described above, the glass plate 33 has a flat plate shape, and has a rectangular shape when viewed from a direction orthogonal to the main surface. In other words, the glass plate 33 has a rectangular parallelepiped shape (rectangular plate shape). As shown in FIG. 2, the glass plate 33 is provided so as to close the first opening 31 a and the second opening 32 a, and the outer peripheral portion of the lower main surface is framed via the glass bonding material 34. It is joined to the outer periphery of the upper surface of the body 32. As a result, the optical device lid 3 is formed which can exchange light between the optical element 2 and the outside via the glass plate 33 and can hermetically seal the optical element 2.

The glass plate 33, the frame 32, the metal frame 31, and the substrate 11 may be made of materials having similar thermal expansion coefficients. The glass plate 33 has a thermal expansion coefficient of, for example, 4 (× 10 ⁻⁶ / ° C.) in order to reduce the possibility of birefringence or breakage, and to improve the reliability of the temperature cycle and the like. A glass material having about ˜8 (× 10 ⁻⁶ / ° C.) may be used. The lid 3 for an optical device according to the embodiment has a configuration that reduces the possibility of birefringence and breakage of the glass plate 33 in addition to the similar thermal expansion coefficient, and details of this configuration will be described later. To do.

The glass plate 33 is, for example, BK7 (manufactured by HOYA, linear thermal expansion coefficient is approximately 7.5 (× 10 ⁻⁶ / ° C.)) or D263 (manufactured by Schott, linear thermal expansion coefficient is approximately 7.2 (× 10 Using a glass material such as ⁻⁶ / ° C.), a conventionally known dicing method or laser cutting method can be used to form a rectangular shape.

  In addition, the glass plate 33 has a shape in which chamfering of each cuboid ridge line is not performed in the figure, but by chamfering each cuboid ridge line on the C surface or the R surface, for example, When the glass plate 33 is formed into a predetermined shape by processing the glass plate 33, it is possible to reduce cracks and the like from microcracks.

  Further, an antireflection film (not shown) may be formed on the front and back surfaces of the glass plate 33. The reflectance with respect to the incident light by the surface of the glass plate 33 is about 1% or less when the antireflection film is formed, compared with about 5% when the antireflection film is formed. it can. In particular, when the optical element 2 is a mirror device, the incident light is reflected. Therefore, by forming antireflection films on both surfaces of the glass plate 33, the light transmittance can be increased by about 16%. As the antireflection film, a multilayer antireflection film in which a dielectric film having a higher refractive index and a lower refractive index than glass is formed on the surface of the glass plate 33, or a single layer film in which a low refractive index dielectric is formed. And an antireflection film in which minute projections called a moth-eye structure are formed on the glass plate 33 at intervals narrower than the wavelength of visible light.

  Here, a method of manufacturing the optical device lid 3 and the optical device 4 will be described.

  As shown in FIGS. 1 and 2, the frame body 32 is bonded onto the metal frame 31 via a bonding material 35 with the second opening 32 a corresponding to the first opening 31 a of the metal frame 31. The Note that the bonding material 35 is, for example, an active metal brazing material.

  When the bonding material 35 is an active metal brazing material, the paste is a silver brazing material composed of silver and copper powder, silver-copper alloy powder, or a mixed powder thereof (for example, silver: 72% by mass) Copper: 28 mass (%)) powder, active metal such as titanium, hafnium, zirconium or hydride thereof is added to and mixed with silver brazing filler in an amount of 2-5 mass (%). It is manufactured by adding and mixing a solvent and a solvent and kneading.

  When joining the metal frame 31 and the frame body 32 with the joining material 35 of the active metal brazing material, the active metal brazing paste is applied to at least one of the joining surfaces of each member by using well-known screen printing or the like, for example, 30 A predetermined pattern is printed and applied with a thickness of (μm) to 50 (μm).

  Then, after the metal frame 31 is placed on the frame body 32 so as to have a predetermined structure, the metal frame 31 is loaded in a non-oxidizing atmosphere such as a hydrogen gas atmosphere or a nitrogen gas atmosphere while applying a load. Joining by heating between 780 (° C) to 900 (° C), 10 (minutes) to 120 (minutes), changing the organic solvent, solvent, and dispersant of the brazing material paste into gas and releasing the gas and melting the brazing material Is done. Moreover, since the metal frame 31 can suppress corrosion by providing a plating layer of nickel or the like, for example, a nickel layer or the like may be provided using a plating method after joining to the frame body 32.

The metal frame 31 is not directly bonded to the frame 32 with the bonding material 35, but a soft metal (not shown) such as a copper plate is bonded to the frame 32 using an active metal, and the copper plate and the metal frame 3 are bonded.
1 may be joined with a brazing material. As a result, the stress applied to the glass can be further reduced.

  As shown in FIG. 2, the glass plate 33 is bonded to the upper surface of the frame 32 to which the metal frame 31 is bonded using a glass bonding material 34. Thus, the optical device lid 3 including the metal frame 31, the frame body 32, and the glass plate 33 is obtained. As the glass bonding material 34, for example, low melting point glass or the like can be used.

  As the glass bonding material 34, a material having a thermal expansion coefficient comparable to that of the frame body 32 or the glass plate 33 may be used. For example, when low melting glass is used as the glass bonding material 34, the low melting glass may have a thermal expansion coefficient comparable to that of the frame body 32 or the glass plate 33. As a result, the stress applied to the glass plate 33 is suppressed, and the glass plate 33 is bonded to the frame-shaped portion 32b of the frame body 32 with high bonding strength.

Further, when the thermal expansion coefficient of the low melting point glass is large, the glass bonding material 34 is obtained by adding a low thermal expansion material such as a cordierite compound as a filler to a thermal expansion coefficient of 4 to 8 (× 10 ^{− By controlling the} temperature to about ⁶ / ° C. or less, the stress applied to the glass plate 33 can be suppressed and the bonding strength can be improved.

  The low-melting glass may be lead-based low-melting glass, but may be made of lead-free glass because of its influence on the environment. The low melting point glass may be made of, for example, bismuth-based lead-free glass that can be bonded at a low temperature of about 450 (° C.) or vanadium pentoxide-based glass that can be bonded at a low temperature of about 400 (° C.).

  When low melting glass is used as the glass bonding material 34, a paste that becomes low melting glass is formed by screen printing over the outer peripheral edge of the lower main surface of the glass plate 33 and the entire periphery of the side surface. Then, after the paste is heated to evaporate the solvent, the glass plate 33 is placed on the frame-like portion 32b of the frame body 32 to which the metal frame 31 is bonded, and maintained at a temperature equal to or higher than the melting point of the low-melting glass. And what is necessary is just to melt-bond. Accordingly, the optical device lid 3 of the present invention including the metal frame 31, the frame body 32, and the glass plate 33 is obtained.

  On the other hand, as shown in FIG. 5, the optical device substrate 1 includes a substrate 11 and a bonding metal ring 12 bonded to the substrate 11. Note that the above-described bonding metallization layer may be provided on the upper surface of the substrate 11, and the substrate 11 and the bonding metal ring 12 may be bonded to each other via a brazing material bonded to the bonding metallization layer. In this case, for example, a brazing material made of a silver-copper eutectic alloy is disposed on the joining metallized layer using an assembly jig, and the joining metal ring 12 is disposed thereon, in a reducing atmosphere. Thus, the substrate 11 (joining metallization layer) and the joining metal ring 12 are joined by holding at a temperature exceeding the melting point of the brazing material.

  Thereafter, after the optical element 2 is mounted on the optical device substrate 1, for example, the optical element 2 is electrically connected to the wiring conductor by a bonding wire using a wire bonding method. Then, the outer peripheral portion of the entire circumference of the metal frame 31 of the optical device lid 3 and the bonding metal ring 12 of the optical device substrate 1 are bonded by seam weld bonding. The optical device base 1 and the optical device lid 3 may be bonded using direct seam bonding or electron beam bonding without using the bonding metal ring 12. Thus, the optical device 4 includes the optical device substrate 1, the optical element 2 mounted on the optical device substrate 1, and the optical device lid 3 bonded to the optical device substrate 1. It will be a thing.

In the optical device lid 3 and the optical device 4 of such an embodiment, the upper surface of the frame body 32 is inclined downward from a pair of one corner portion 321 located on one diagonal line to the other corner portion 322. It is an inclined surface. According to the inclination of the upper surface of the frame body 32, the glass plate 33 in which the outer peripheral portion of the lower surface is joined to the upper surface of the frame body 32 is also inclined. In the present embodiment, the inclination angle θ1 of the glass plate 33 is the same angle (θ1) with respect to the long side direction and the short side direction of the rectangular (rectangular) frame shape. The inclination angle of the glass plate 33 is an inclination angle of the lower surface of the glass plate 33 with respect to a virtual plane in the xy direction.

  Therefore, the upper surface of the frame 32 has a rectangular frame shape when viewed from a direction perpendicular to the upper surface of the substrate 11 (in top view), that is, when viewed from the positive side in the z direction to the negative direction. When viewed from a direction perpendicular to the upper surface of the body 32 (in a plan view), the length of the one diagonal line is longer than the length of the other diagonal line intersecting this. For example, if the upper surface of the frame 32 is a square frame shape in plan view, the frame body 32 has a rhombus shape when viewed from a direction perpendicular to the upper surface.

  For example, as in the example shown in FIG. 3, a rectangular glass plate 33 is bonded to the upper surface of such a frame 32. FIG. 3 is a plan view seen from a direction perpendicular to the upper surface of the frame 32 of the lid 3 for the optical device shown in FIG. That is, it is a view of the optical device lid 3 as viewed obliquely from above. Because of this configuration, the distance from the outer periphery of the frame 32 to the outer periphery of the glass plate 33 is greater than the one corner 321 in the other corner 322 of the pair of corners on the one diagonal L. Is also big. As a result, in the other corner portion 322 having the smallest height (dimension in the z direction, that is, thickness) of the frame body 32, that is, in the portion of the frame body 32 where stress is most likely to be concentrated in the manufacturing process or the like, The range of joining of the plate 33 and the frame body 32 can be minimized. In FIG. 3, the one diagonal line L is shown as an imaginary line (two-dot chain line).

  That is, according to the lid 3 for an optical device of the present embodiment, since it has the above-described configuration, it is difficult to apply a stress such as a compressive stress to the glass plate 33, and the residual stress is effectively reduced. Is done. Therefore, it is possible to provide the optical device lid 3 in which the possibility of birefringence due to the residual stress is reduced and the optical device 4 having excellent characteristics such as images can be easily formed.

  In FIG. 3, the thickness of the frame body 32 is reduced from the top to the bottom of the figure. Therefore, in the part below the left and right corners in FIG. 3, the cross section of the frame body 32 is observed radially from the center. In this case, the outer portion is formed thinner than the inner portion in the same cross section. When the metal frame 31 is joined to the frame 32 at the thin part of the outer part of the frame 32 and the glass plate 33 is joined to the inner part thicker than the part of the frame 32 where the metal frame 31 is joined. Since the stress is easily relieved by the frame body 32, the possibility of birefringence is further reduced.

  Further, as described above, the optical device cover 3 having the above-described configuration and the upper surface including the mounting portion (such as the recess 11a) of the optical element 2 are provided, and the optical device is used so as to surround the mounting portion on the upper surface. The board | substrate 11 with which the cover body 3 is arrange | positioned is included. According to such an optical device 4, since the optical device lid 3 having the above-described configuration is provided, the optical device 4 in which problems such as birefringence are effectively suppressed can be provided.

  The optical device lid 3 may be such that the width of the upper surface of the frame 32 is smaller on the short side than on the long side as in the example of FIG. 6. That is, the width of the upper surface of the frame 32 may be relatively large on the long side. 6A is a top view showing a first modification of FIG. 2A, FIG. 6B is a cross-sectional view taken along line AA of FIG. 6A, and FIG. (C) is sectional drawing in the BB line of Fig.6 (a). In FIG. 6, the same parts as those in FIG.

In this case, the rigidity on the long side of the frame 32 is further increased, and the rigidity on the long side is further increased in the lid 3 for the optical device. Thereby, the stress applied to the glass plate 33 is difficult to increase, and the glass plate 33 is difficult to break. Therefore, in this case, for example, it becomes easy to cope with an increase in size as the optical device lid 3. That is, the optical device lid 3 and the optical device 4 having the optical device lid 3 that can easily produce the optical device 4 having excellent optical characteristics in response to a further increase in stress applied to the glass plate 33 are provided. be able to.

  The optical device lid 3 further includes a metal frame 31 joined to the lower surface of the frame 32 as in the above example, and the outer periphery of the metal frame 31 is more than the outer periphery of the frame 32. It may be located outside.

  In this case, the outer peripheral portion of the metal frame 31 located outside the outer periphery of the frame body 32 can be used for joining to the joining metal ring 12. Moreover, it is suppressed more effectively that the stress at the time of the joining is added to the glass plate 33 from the frame 32. Therefore, it is possible to provide the optical device lid 3 that is more effective for reducing the possibility of birefringence and improving productivity, and the optical device 4 having the same.

  Further, the inclination angle of the upper surface of the frame 32 may be smaller in the long side direction of the glass plate 33 than in the short side direction as in the example of FIG. That is, θ1 <θ2 may be satisfied in the example shown in FIG. The inclination angle of the upper surface of the frame body 32 is an angle formed by the upper surface of the frame body 32 and a virtual plane in the xy direction as described above. If this virtual plane and the upper surface of the frame body 32 are parallel to each other (not shown), the angle of inclination of the upper surface of the frame body 32 is 0 degrees. In this embodiment, both θ1 and θ2 are used. Greater than 0 degrees. 7A is a top view showing a second modification of FIG. 2A, FIG. 7B is a cross-sectional view taken along line AA of FIG. 7A, and FIG. (C) is sectional drawing in the BB line of Fig.7 (a). In FIG. 6, the same parts as those in FIG.

  In this case, the inclination of the upper surface of the frame body 32 is smaller in the longer long side direction, that is, the change in the thickness of the frame body 32 is smaller. Therefore, for example, it becomes easier to reduce the height of the optical device lid 3 and the optical device 4.

DESCRIPTION OF SYMBOLS 1 Optical apparatus base | substrate 11 Board | substrate 12 Joining metal ring 2 Optical element 3 Optical apparatus cover body 31 Metal frame 31a 1st opening part 31b Frame-shaped part 32 Frame body 32a 2nd opening part 32c Side wall 321 One corner | angular part 322 The other corner 33 Glass plate 34 Glass bonding material 35 Bonding material 4 Optical device

Claims (5)

A frame having an upper surface and a lower surface each having a rectangular outer periphery and inner periphery in top perspective;
A rectangular lower surface, and an outer peripheral portion of the lower surface includes a glass plate bonded to the upper surface of the frame body,
The lid for an optical device, wherein the upper surface of the frame is an inclined surface that is inclined downward from one to the other of a pair of corners located on one diagonal line. 2. The optical device lid according to claim 1, wherein a width of the upper surface of the frame is smaller on a short side than on a long side. A metal frame joined to the lower surface of the frame body;
2. The lid for an optical device according to claim 1, wherein an outer periphery of the metal frame is located outside an outer periphery of the frame body. 2. The optical device lid according to claim 1, wherein an angle of inclination of the upper surface of the frame body is smaller than a short side direction in a long side direction of the glass plate. A lid for an optical device according to claim 1,
A substrate having an upper surface including a mounting portion of the optical element, and the optical device lid disposed on the upper surface so as to surround the mounting portion;
An optical device comprising: an optical element mounted on the mounting portion.

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