JP6971768B2 - Optical equipment and modules - Google Patents

Description

The present invention relates to an optical device and an optical module including a light emitting element and a reflector of laser light.

Optical modules are known by utilizing the reflection of light such as a laser beam that detects and measures an object. The optical module has a light emitting part such as a laser beam, a reflecting part that reflects the emitted light and guides it toward an object located outside the optical module, and a light receiving part that receives the light reflected by the object. Have. The light receiving unit receives the light radiated to the outside and reflected by the object, and the existence of the object, the distance to the object, and the like can be measured. As described in Patent Document 1, for example, the light emitting portion is arranged separately from the reflecting portion in consideration of effective irradiation of light on the object to be measured.

Japanese Unexamined Patent Publication No. 2001-108758

In the above optical module, it is required to reduce the number of components constituting the module and improve the workability of alignment between the components.

The optical device of one aspect of the present invention includes a radiation unit and a container unit having a positioning unit. The radiation unit includes a light emitting element of laser light, a MEMS element having a movable reflecting surface, and a plurality of reflectors each having a reflecting surface. Further, the reflective surface of the reflector is positioned so as to reflect the laser beam emitted from the light emitting element to the movable reflective surface of the MEMS element. The container portion includes a substrate having at least one recess and a lid for closing the recess, and has the radiation portion on the inner surface of the substrate and the lower surface of the lid in one recess. The light emitting element, the MEMS element, and the reflector are positioned and fixed in the vicinity of the positioning portion. The positioning unit includes a mark indicating a fixed position of the light emitting element, the MEMS element and the reflector, a protrusion and / or a groove portion, and the light emitting element, the MEMS element and the reflector are each included. , It is fixed to the container portion based on the corresponding fixing position.

The optical module according to one aspect of the present invention includes a light emitting unit including the optical device having the above configuration and a light receiving unit including a light receiving element that receives the laser beam.

According to the optical device of one aspect of the present invention, since the light emitting element, the MEMS element and the reflector are located in the container portion having the positioning portion in the above configuration, the light emitting element, the MEMS element and the reflector are combined. It is easy to align with each other. Further, since the light emitting element, the reflector, and the like are located in the container portion, the optical module can be configured only by the optical device and the light receiving portion. Therefore, it is also effective in reducing the number of parts.

According to the optical module in one aspect of the present invention, since the optical device having the above configuration is included, it is effective for reducing the number of parts and improving the workability of alignment between parts.

It is sectional drawing which shows the optical apparatus of embodiment of this invention. It is a top view which shows a part of the optical apparatus of embodiment of this invention. It is sectional drawing which shows the optical apparatus and optical module of embodiment of this invention. It is sectional drawing which shows the modification of the optical apparatus shown in FIG.

An optical device and an optical module according to an embodiment of the present invention will be described with reference to the drawings. The figures used in the following description are schematic. Further, the distinction between upper and lower in the following description is for convenience of explanation and does not regulate the upper and lower when the optical device and the optical module are actually used. Further, the "incident angle" in the following description is an angle formed by the surface of the object on which the light is incident and the optical axis of the light, and is 0 to 90 degrees for convenience of explanation. That is, the angle of incidence when light is incident along a perpendicular or normal to the surface of an object is defined as 90 degrees.

FIG. 1 is a cross-sectional view showing an optical device according to an embodiment of the present invention. FIG. 2 is a plan view showing a part of the optical device according to the embodiment of the present invention. Further, FIG. 3 is a cross-sectional view showing an optical device and an optical module according to an embodiment of the present invention.

In FIGS. 1 and 2, the optical device 10 includes a radiation unit A that emits laser light to the outside, and a container unit B that holds the radiation unit A in a predetermined positional relationship and seals the radiation unit A. In FIG. 2, the radiation portion is omitted in order to make the container portion easier to see. Further, as shown in FIG. 3, the optical module 20 is basically composed of a light emitting unit C including an optical device 10 and a light receiving unit D including a light receiving element 11 for receiving laser light. The optical module 20 receives the laser light emitted from the light emitting unit C to the outside by the object to be detected E and returned (hereinafter referred to as externally reflected light) by the light receiving unit C. Based on the information of the externally reflected light, information such as the presence / absence of the object to be detected E, the shape, the dimensions, the speed of movement, and the like are calculated and detected. The object to be detected E is, for example, a pedestrian E1 and a vehicle E2.

The radiation unit A includes a light emitting element 1 for laser light, a MEMS (Micro Electro Mechanical Systems) element 2 having a movable reflection surface 2a, and a plurality of reflectors 3 each having a reflection surface 3a. As shown in FIG. 3, the plurality of reflectors 3 are positioned so that the respective reflecting surfaces 3a reflect the laser beam L emitted from the light emitting element 1 on the movable reflecting surface 2a of the MEMS element 2. That is, the laser beam L emitted from the light emitting element 1 is reflected twice by the reflecting surface 3a of the reflector 3 and guided to the movable reflecting surface 2a of the MEMS element 2. The laser beam L is reflected by the movable reflecting surface at different angles in terms of diameter, and is radiated to the outside from the optical device 10 at a wide angle.

The container portion B includes a substrate 4 having at least one recess 4a and a lid 5 for closing the recess 4a. Further, the positioning portion 6 of the radiation portion A is provided on the inner surface of the substrate 4 and the lower surface of the lid 5 in one recess 4a. The light emitting element 1, the MEMS element 2, and the reflector 3 are positioned and fixed in the vicinity of these positioning portions 6. By this positioning, as described above, the laser beam L can be easily and accurately reflected from the light emitting element 1 to the movable reflecting surface 2a of the MEMS element 2 and guided.

The light emitting element 1 is a semiconductor element or the like that emits a laser beam L, and is, for example, a semiconductor laser (laser diode). The light emitting device 1 is configured by laminating compound semiconductor materials such as GaN (gallium nitride) or Ga-As (gallium-arsenide) to form a plurality of layers, p-layers and n-layers. In the example shown in FIG. 1 and the like, the interface between the p layer and the n layer is located on the side surface of the block-shaped light emitting element 1, and light is emitted from this portion. That is, the side surface of the light emitting element 1 can be regarded as a light emitting surface. The light emitting device 1 is not limited to the above-mentioned material, and may contain a compound semiconductor material appropriately selected from Al-Ga-As, In-Ga-Al-P, In-Ga-N, ZnO and the like.

The laser beam L emitted from the light emitting element 1 is not limited to visible light (for example, purple to blue or red), and may be ultraviolet rays or infrared rays. Further, the laser beam L is not limited to continuously emitted light (continuous light), and may be pulsed light. For example, if the optical device 10 and the optical module 20 measure the distance to the object to be detected E, a light emitting element 1 that emits modulated continuous light or pulsed light is used. The selection of these laser beams L can be appropriately determined according to conditions such as the use, function, type and quantity of the object E to be detected, and economic efficiency of the optical device 10 and the optical module 20.

The light emitting element 1 is joined to and fixed to the bottom portion of the recess 4a (the upper surface of the convex mount portion located on the bottom surface of the recess 4a in the example of FIG. 1) by a first bonding material 7 such as a gold-tin brazing material. ing. Since the light emitting element 1 is joined to the upper surface of the mount portion, the height position of the laser beam L radiated from the side surface thereof can be separated upward from the bottom surface of the recess 4a. Therefore, the height position of the laser beam L can be aligned with the substantially central portion of the reflecting surface 2a of the reflector 2, which will be described later.

The mount portion may be made of the same material as the substrate 1, or may have another component disposed on the bottom surface of the recess 4a. Examples of the separate parts include temperature control parts such as a Pelche element, heat transfer parts made of a metal material, and cushioning materials made of a resin material having a lower elastic modulus than the substrate 4.

The MEMS element 2 has a fine circuit conductor and a mechanically movable mechanism formed on the surface of a semiconductor substrate such as a silicon substrate. The MEMS element in the example of this embodiment has the above-mentioned movable reflecting surface 2a as a mechanically movable mechanism. The movable reflective surface 2a is a micromirror manufactured by applying the medical technique for forming a semiconductor integrated circuit. A micromirror is arranged on the upper surface of the MEMS element 2. The micromirror is held by a biaxial holding portion, a so-called beam, provided on the semiconductor substrate, and can be tilted according to the tilt of the shaft. In the micromirror, the reflection surface can move (change the reflection angle) as described above according to information such as an electric signal transmitted via a circuit conductor located on the upper surface of the MEMS element 2 or the like. That is, the incident laser beam L can be reflected by changing the reflection angle with time. In other words, the MEMS element 2 makes it possible to radiate the laser beam L so as to scan the outside of the optical device 10 at a wide angle.

The MEMS element 2 can be manufactured by applying a microfabrication technique such as a photolithography to an exposed surface such as the upper surface of a semiconductor substrate such as a silicon substrate as described above to form an integrated circuit. Further, the MEMS element 2 may be joined and fixed to the bottom portion (bottom surface in the example of FIG. 1) of the recess 4a by the second joining material 8 having a lower joining temperature than the first joining material 7. In this case, since the first bonding material 7 does not melt when the second bonding material 8 is used for bonding, misalignment of the previously fixed light emitting element 1 is unlikely to occur. That is, it is effective for improving the position accuracy of the radiation unit A. Examples of the second bonding material 8 include a bonding material in which fine particles (so-called nanoparticles) at the submicron level of metal are mixed with an organic binder. In addition, in FIG. 3 and FIG. 4 which will be referred to later, the first joining material 7 and the second joining material 8 are omitted for the sake of simplicity.

As described above, in the plurality of reflectors 3 having each reflecting surface 3a, the reflecting surface 3a reflects the laser beam L emitted from the light emitting element 1 on the movable reflecting surface 2a of the MEMS element 2. positioned. The position of the reflecting surface 3a that reflects the laser beam emitted from the light emitting element 1 to the movable reflecting surface 2a of the MEMS element 2 is, for example, as described below.

In the example shown in FIGS. 1 to 3, a first reflector having a plurality of reflectors 3 located adjacent to the light emitting element 1 and having a reflecting surface 3a for reflecting the laser beam L in the direction of the lid 5. 3 (3A) and a second reflector 3 (3B) having a reflecting surface 3a located on the lower surface of the lid 5 and diagonally facing the reflecting surface 3a of the first reflector 3 (3A). Includes. In the following, the first reflector 3 (3A) and the second reflector 3 (3B) are simply referred to as the first reflector 3A and the second reflector 3B. Further, these reflectors 3 (3A, 3B) are not particularly distinguished, and may be simply referred to as a reflector 3.

The first reflector 3A is located adjacent to the light emitting surface of the light emitting element 1. The reflective surface 3a of the first reflector 3A is slanted with respect to the light emitting surface and is obliquely opposed to the lid 5. As a result, the laser beam L emitted from the side surface of the light emitting element 1 can be reflected in the direction of the lid 5. The laser beam L is reflected from the first reflector 3A in the direction of the lid 5, and its optical axis is slanted with respect to the lid 5.

The second reflector 3B is obliquely opposed to the reflecting surface 3a of the first reflector 3A. As a result, the laser beam L that travels diagonally with respect to the lower surface of the lid 5 can be specularly reflected and reflected in the direction of the MEMS element 2 located diagonally below the second reflector 3B. That is, each reflecting surface 3a is positioned so as to reflect the laser beam L emitted from the light emitting element 1 on the movable reflecting surface 2a of the MEMS element 2.

The laser beam L reflected from the light emitting element 1 by the plurality of reflectors 3 and reaching the MEMS element 2 is reflected by the movable reflecting surface 2a and radiated to the outside of the light emitting device 10 and the light emitting module 20 as described above. .. Since the radiation angle of the emitted laser light L changes with time as described above, it is possible to scan the outside with the laser light L to obtain an external reflected light LB containing information on the object to be detected E. can.

The first reflector 3A is, for example, a mirror, and is fixed to the bottom of the recess 4a by a second bonding material 8. The mirror surface portion on the outermost surface of the mirror is the reflection surface 3a. As the second bonding material 8, the same material as the second bonding material 8 for bonding the MEMS element 8 can be used. Further, the second reflector 3B is a thin film layer (so-called thin film mirror) made of a metal material such as gold having a high reflection efficiency of the laser beam L, for example. The second reflector 3B can be provided on the lower surface of the lid 5 by a thin film method such as vapor deposition. The second reflector 3B, which is a thin film mirror, can be regarded as one in which the reflecting surface 3a and the main body are integrated.

The MEMS element 2 also has a function of reflecting the externally reflected light LB again and causing the light receiving element 11 located outside to receive the externally reflected light LB. That is, the externally reflected light LB is specularly reflected by the movable reflecting surface 2a, passes through the lid 5, and is received by the external light receiving element 11. Also in this case, since the reflecting surface of the MEMS element 2 is movable, the externally reflected light LB returning at different angles can be reflected in the direction of the light receiving element 11 at any time.

The substrate 4 has a recess 4a on the upper surface thereof, and has a function as a container body for accommodating the radiation portion A in the recess 4a. The substrate 4 is formed of a ceramic material such as an aluminum oxide sintered body, an aluminum nitride material sintered body, a silicon nitride material sintered body, a mullite material sintered body, or a glass ceramic sintered body. The substrate 4 can be manufactured as follows, for example, if it is made of an aluminum oxide sintered body. first. Raw material powders such as aluminum oxide, silicon oxide and calcium oxide are kneaded with a suitable organic solvent and binder to prepare a slurry. Next, this slurry is formed into a sheet by a method such as a doctor blade method, and then cut into a predetermined shape (a shape having an opening to be a recess 4a, etc.) and dimensions to prepare a plurality of sheets. After that, the substrate 1 can be manufactured by laminating these sheets and firing them.

Further, the substrate 4 can also be manufactured by a method of molding the above-mentioned ceramic raw material into a predetermined shape of the substrate 4 by a method such as press working and firing. Further, the substrate 4 may be made of an organic resin such as an epoxy resin. In this case, the substrate 4 can be manufactured by a method in which a resin material such as an uncured epoxy resin is molded into a predetermined shape by means such as a molding die and then heat-cured.

The substrate 1 may have other recesses (not shown) in addition to the one recess 4a on which the radiation portion A is mounted. Examples of the other recesses include those located on the lower surface of the substrate 4 for accommodating various electronic components such as a chip capacitor, a resistance element, or an antenna element. The opening size of such other recesses is smaller than the opening size of the recess 4a.

The lid 5 has a function of closing the recess 4a and airtightly sealing the radiation portion A (particularly, the light emitting element 1 and the MEMS element 2). Further, the lid 5 is made of a material capable of transmitting the laser beam L in order to allow the laser beam L to be emitted from the radiating portion A to the outside while enabling such airtight sealing. In the examples shown in FIGS. 1 to 3, the lid 5 is formed of a translucent glass material. In FIGS. 1 to 3, the lid 5 made of a translucent material is not hatched.

As described above, the positioning portion 6 of the container portion B has a function of facilitating and highly accurate positioning of the radiation portion A in the container portion B. Examples of the positioning portion 6 include a mark 6a located on the bottom surface of the recess 4a, a groove portion 6b, and the like, as in the example shown in FIG. The mark 6a is, for example, a metal layer, and can be provided in the recess 4a, the lower surface of the lid 5, or the like in the form of a metallized layer, a plating layer, a metal foil, a thin film layer, or the like. The positioning portion 6 is not limited to these examples, and may be a protruding portion or a combination of a plurality of types.

The mark 6a indicates a position corresponding to a corner portion of the mounting range of the MEMS element 2 to be mounted. By aligning the four corners of the MEMS element 2 with the position of the mark 6a, the MEMS element 2 can be mounted at a predetermined position on the bottom surface of the recess 4a.

The groove portion 6b is provided so as to match the connection position of the mount of the light emitting element 1 and the mirror (first reflector). By fitting the mount and the mirror of the groove 6b, respectively, the light emitting element 1 and the first reflector 3A can be positioned and fixed in the recess 4a.

The lower surface of the lid 5 may also be provided with a positioning portion (not shown) such as a mark similar to the above. As a result, positioning of the thin layer layer to be the second reflector 3B with respect to the lower surface of the lid 5 is easily performed with high accuracy. Further, the second reflector 3B may be located on the upper surface of the lid 5, and in this case, a positioning portion may be provided on the upper surface of the lid 5. Even when the second reflector 3B is located on the upper surface of the lid 5, the laser beam L transmitted through the lid 5 is reflected in the direction of the MEMS element 2 and is transmitted through the lid 5 again to transmit the MEMS element 2. Can be sent to. Further, when the positioning portion 6 is located on the lower surface or the upper surface of the lid 5, the positioning portion 6 may be arranged on the opposite surface (upper surface or lower surface).

According to such an optical device 10, since the light emitting element 1, the MEMS element 2 and the reflector 3 are located in the container portion B having the positioning portion 6, the light emitting element 1, the MEMS element 2 and the reflector 3 are combined. It is easy to align with each other. Further, since the light emitting element 1 and the reflector 3 are located in the container portion B, the optical module 20 can be composed only of the optical device 10 and the light receiving portion D. Therefore, it is also effective in reducing the number of parts.

In the light emitting device 10 and the light emitting module 20, as in the above example, a plurality of reflectors 3 are located adjacent to the light emitting element 1 and the reflecting surface 3 reflects the laser beam L in the direction of the lid 5.
A first reflector 3A having a, and a second reflector 3B having a reflecting surface 3a located on the lower surface or the upper surface of the lid 5 and diagonally facing the reflecting surface 3a of the first reflector 3A. When the above is included, the following forms may be further provided. That is, in the above configuration, when the light emitting device 10 and the light emitting module 20 are viewed facing the upper surface of the lid 5, the central portion of the second reflector 3B is the movable reflecting surface 2a of the MEMS element 2 and the first reflection. It may be located between the reflecting surface 3a of the body 3A.

In this case, the difference in distance from each of the movable reflective surface 2a of the MEMS element 2 and the reflective surface 3a of the first reflector 3A to the central portion of the second reflector 3B can be effectively reduced. Therefore, the laser beam L that is specularly reflected by the reflecting surface 3a of the second reflector 3B reaches the movable reflecting surface 2a efficiently. Therefore, it is effective for improving the intensity of the laser beam L radiated to the outside.

Further, in this case, it is reduced that the second reflector 3B and the movable reflective surface 2a of the MEMS element 2 overlap each other when viewed facing the upper surface of the lid 5. Further, the apparent size of the second reflector 3B when viewed from the movable reflecting surface 2a is smaller than that when facing each other. Therefore, when the externally reflected light LB reflected by the object to be detected E and returned is reflected again by the movable reflecting surface 2a and emitted from the lid 5 in the direction of the light receiving portion D, the emission is emitted from the second reflector. The possibility of being hindered by 3B can be effectively reduced.

Further, when viewed facing the upper surface of the lid 5, the central portion of the second reflector 3B is located between the movable reflecting surface 2a of the MEMS element 2 and the reflecting surface 3a of the first reflector 3A. In this case, when the outer edge of the second reflector 3B is located outside the outer peripheral portion of the movable reflecting surface 2a of the MEMS element 2, the external reflected light LB as described above is easily emitted to the outside. Moreover, it is possible to obtain the effect of efficiently performing the effect more reliably.

FIG. 4 is a cross-sectional view showing a modified example of the optical device 10 shown in FIG. In FIG. 4, the same parts as those in FIGS. 1 to 3 are designated by the same reference numerals. Using this optical device 10, the optical module 20 can be manufactured in the same manner as described above. In the optical device 10 of this modification, the MEMS element 2 is located at the bottom of the recess 4a so that the movable reflective surface 2a is inclined toward the reflective surface 3a of the second reflector 3B. Tilt in the direction of the reflective surface 3a of the second reflector 3B means that the end portion of the movable reflective surface 2a farther from the second reflector is located above the end portion closer to the second reflector. Is tilted.

In the example shown in FIG. 4, a part of the bottom surface of the recess 4a is an inclined surface, and the MEMS element 2 is mounted on the inclined surface, and the movable reflective surface 2a is inclined in the direction of the second reflector 3B. .. Not limited to this, a mounting material that inclines the MEMS element may be arranged on the bottom surface of the flat concave portion 4a, or the inclined surface may be slightly curved. In FIG. 4, the position when the movable reflection surface 2a is tilted around one axis (one of the above-mentioned “beams”) is schematically shown by a broken line.

In such a case, the projected area when the MEMS element 2 is projected onto the bottom surface of the recess 4a is smaller than that when the MEMS element 2 is not tilted. Further, the scanning range of the reflected light (hereinafter, also simply referred to as the reflected light L), which is the laser light L reflected by the movable reflecting surface 2a and incident on the lid 5, is displaced toward the center in the plan view of the lid 5. Can be done. Therefore, the reflected light L (for example, L1 in FIG. 4) reflected at a small angle with respect to the movable reflecting surface 2a can be delivered to the lid 5 within the range of the lid 5 and radiated to the outside. In other words, it is not necessary to widen the lid 5 outward in a plan view with respect to the MEMS element 2 for the purpose of allowing the reflected light L to pass through the lid 5. Therefore, it is advantageous for the miniaturization of the lid 5 in a plan view, that is, the optical device 10.

In the example shown in FIG. 4, the incident angle Lθ of the reflected light L1 with respect to the lid 5 is about 30 degrees. Further, the incident angle Lθ with respect to the lid 5 of the reflected light L (for example, L2 in FIG. 4) reflected at a relatively deep angle with respect to the movable reflecting surface 2a is about 90 degrees. That is, even if the distance between the movable reflecting surface 2a and the lid 5 is smaller than that shown in FIG. 1, for example (that is, even if the thickness of the optical device 10 is reduced), the lid of the reflected light L is covered. The incident angle Lθ with respect to 5 can be secured up to 90 degrees, and the amount of radiated light to the outside can be easily secured. Therefore, the optical device 10 of this modification is also effective for thinning.

Further, in the example shown in FIG. 4, the incident angle LBθ of the externally reflected light LB with respect to the lid 5 is 30 to 90 degrees, which is the same as the incident angle Lθ of the laser light (reflected light) L. Such externally reflected light LB is re-reflected by the movable reflecting surface 2a, passes through the lid 5, reaches the light receiving portion (not shown in FIG. 4), and is received by the light receiving element.

As described above, the light emitting module 20 of the embodiment includes a light emitting unit C including an optical device 10 having any of the above configurations, and a light receiving unit including a light receiving element 11 for receiving laser light (external reflected light LB). ing. The laser beam emitted from the outside by the light emitting unit C is reflected by the object to be detected E and returned, and is detected by the light receiving unit D. The presence / absence of the object to be detected E, the presence / absence position, and the presence / absence of the detected object E based on the presence / absence of the return of the laser beam, the reflected position (presence / absence of the return of the laser beam depending on the direction of radiation), the time required from the radiation to the light reception, and the like. Information such as the shape and the distance to the object to be detected E is calculated and measured.

In this case, the optical module may include an arithmetic unit (semiconductor integrated circuit element or the like) necessary for arithmetic processing of the light receiving information in the light receiving unit D. Further, an electric circuit capable of transmitting and receiving an electric signal may be arranged between the light emitting unit C and the light receiving unit D. Terminals 12 for such electrical connections may be arranged.

Further, in the optical device 10, a wiring conductor (not shown) for supplying electric power and electric signals necessary for operation such as supply of electric power to the light emitting element 10 and tilting of the movable reflective surface 2a (micromirror) of the MEMS element 2. ) May be provided on the substrate 4 or the like. Wiring conductors are provided in a predetermined pattern at predetermined positions such as the surface (inner surface of the recess 4a) located in the recess 4a and the inside of the substrate 4 in the substrate 4.

As an example of the wiring conductor, a conductor located from the bottom surface of the recess 4a to the bottom surface or the outer surface of the substrate 4 can be mentioned. The MEMS element 2 and the light emitting element 1 are electrically connected to the portion of the wiring conductor located on the bottom surface of the recess 4a by a conductive connecting material such as a bonding wire or solder. A portion of the wiring conductor located on the lower surface or the outer surface of the substrate 4 is electrically connected to the external electric circuit by a conductive connecting material such as solder or a conductive adhesive. As a result, the MEMS element 2 and the light emitting element 1 are electrically connected to each other in an external electric circuit, and electric power or an electric signal can be transmitted and received.

The wiring conductor can be formed of, for example, a metal material such as tungsten, molybdenum, manganese, copper, silver, palladium, gold, platinum, titanium, nickel and cobalt, or a metal material of an alloy containing these as a main component. Further, the wiring conductor can be formed in various forms such as a metallized layer, a plating layer and a thin film layer. If the wiring conductor is made of a metallized layer of tungsten, for example, a method of printing a metal paste prepared by kneading tungsten powder with an organic solvent and a binder on a predetermined portion of a sheet to be a substrate 4 and firing it. Can be formed with. The exposed surface of the metallized layer may be covered with a plating layer such as nickel and gold.

The object to be detected E detected by the optical module 20 is, for example, a pedestrian E1 and a vehicle E2 as described above. The optical module 20 in this case is a so-called LIDAR (Light Detect).
Ion and Ranging), which can be mounted on a vehicle to detect and measure information such as the presence or absence of pedestrians, the positions of other vehicles and obstacles, and the position of white lines on the road, which are necessary for driving. Such information can be used for vehicle driving assistance and autonomous driving.

The present invention is not limited to the above embodiments, and various modifications can be made within the gist of the present invention. For example, the optical device 10 and the optical module 20 can be used not only for vehicle driving support and automatic driving, but also for detecting non-metal objects that are difficult to detect by radar (radio waves). For example, the light emitting device 10 and the optical module 20 can be used for observing terrain, vegetation, etc. from an aircraft, a drone, or the like.

Further, a light emitting device and an optical module in which the reflecting portion is composed of three or more reflectors may be used, and the reflector may be formed on a portion other than the bottom of the recess 4a and the lower surface of the lid 5, for example, the inner surface of the recess 4a. It may be a light emitting device and an optical module located.

1 ... Light emitting element 2 ... MEMS element 2a ... Movable reflective surface 3 ... Reflector 3A ... First reflector 3B ... Second reflector 3a ... Reflective surface 4 ...・ Base 4a ・ ・ ・ Recessed part 5 ・ ・ ・ Cover body 6 ・ ・ ・ Positioning part 6a ・ ・ ・ Mark 6b ・ ・ ・ Groove part 7 ・ ・ ・ First joint material 8 ・ ・ ・ Second joint material
10 ・ ・ ・ Optical device
11 ・ ・ ・ Light receiving element
12 ・ ・ ・ Terminal
20 ... Optical module A ... Radiation part B ... Container part C ... Light emitting part D ... Light receiving part E ... Detected object E1 ... Pedestrian E2 ... Vehicle L ...・ ・ Laser light (reflected light)
L1, L2 ... Reflected light LB ... External reflected light

Claims (6)

The movable reflection of the MEMS element includes a light emitting element of laser light, a MEMS element having a movable reflecting surface, and a plurality of reflectors each having a reflecting surface, and the reflecting surface emits laser light from the light emitting element. The radiator, which is located to reflect on the surface,
A substrate having at least one recess and a lid for closing the recess are included, and the positioning portion of the radiation portion is provided on the inner surface of the substrate and the lower surface of the lid in the recess. In close proximity to the portion, the light emitting element, the MEMS element, and the container portion in which the reflector is positioned and fixed are provided.
The positioning portion includes marks, protrusions and / or grooves indicating the fixed positions of the light emitting element, the MEMS element and the reflector.
An optical device in which the light emitting element, the MEMS element, and the reflector are fixed to the container portion based on the corresponding fixed positions, respectively. The plurality of reflectors are located adjacent to the light emitting element and have a reflecting surface for reflecting the laser beam in the direction of the lid, and are located on the lower surface or the upper surface of the lid. A second reflector having a reflective surface diagonally opposed to the reflective surface of the first reflector is included.
Claim 1 in which the central portion of the second reflector is located between the movable reflective surface of the MEMS element and the reflective surface of the first reflector when viewed facing the upper surface of the lid. The optical device of the description. The optical device according to claim 2, wherein the outer edge of the second reflector is located outside the outer peripheral portion of the movable reflecting surface of the MEMS element when viewed facing the upper surface of the lid. The light emitting element is bonded to the bottom of the recess via the first bonding material.
2. Claim 2 in which the MEMS element and the first reflector are bonded to the bottom of the recess via a second bonding material having a bonding temperature lower than the bonding temperature of the first bonding material. Or the optical device according to claim 3. The optical device according to any one of claims 2 to 4 , wherein the MEMS element is located at the bottom of the recess so that the movable reflective surface is inclined toward the reflective surface of the second reflector. .. A light emitting unit including the optical device according to any one of claims 1 to 5.
An optical module including a light receiving unit including a light receiving element that receives the laser beam.

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