JP2023039772A - optical device - Google Patents

Abstract

To provide an optical device with which it is possible to detect with high accuracy the luminous energy of light emitted from each of a plurality of mounted light-emitting elements.SOLUTION: An optical device 1 comprises: a substrate; a first light-emitting element mounted to the substrate, for emitting first light having a first wavelength; a second light-emitting element for emitting second light having a second wavelength that is different from the first wavelength; an optical element for emitting emitted light from an other end in correspondence to the fact that light is entered from the first light-emitting element; a first photoelectric conversion element for outputting a current from the first light-emitting element that corresponds to the luminous energy of the first light; a second photoelectric conversion element for outputting a current from the second light-emitting element that corresponds to the luminous energy of the second light; and a first shield wall located between the first light-emitting element and first photoelectric conversion element and the second light-emitting element and second photoelectric conversion element, for preventing the first light from entering the second photoelectric conversion element and preventing the second light from entering the first photoelectric conversion element.SELECTED DRAWING: Figure 6

Description

The present invention relates to optical devices.

2. Description of the Related Art In an optical device using laser diodes that emit red, green, and blue light as light emitting elements, a technique for detecting the amount of light emitted from each of the laser diodes is known. For example, Patent Literature 1 describes a technique in which a part of emitted light is split by a mirror and the light intensity of the split light is detected by a photodiode. In the technique described in Patent Document 1, by adopting a photodiode having sensitivity characteristics capable of detecting wavelengths of red, green, and blue light from 440 nm to 640 nm, the light amount of combined light mixed with three colors is detected. It can be detected with high sensitivity.

JP 2016-15415 A

However, in the technique described in Patent Document 1, in order to detect the light intensity of the combined light in which the three colors are mixed, the light intensity of the light emitted from each of the laser diodes emitting red, green, and blue light is separately measured. Not easy to detect. By arranging the photodiodes in the vicinity of the respective laser diodes, it is possible to separately detect the amount of light emitted from each of the laser diodes. However, when laser diodes are arranged adjacently, light may enter from other laser diodes arranged adjacently, and the detection accuracy of the amount of light emitted from each of the laser diodes may decrease. .

SUMMARY OF THE INVENTION It is an object of the present invention to solve such problems and to provide an optical device capable of detecting with high accuracy the amount of light emitted from each of a plurality of mounted light emitting elements.

An optical device according to the present invention includes a substrate, a first light emitting element mounted on the substrate and emitting a first light having a first wavelength, and a first light emitting element arranged on the substrate side by side with the first light emitting element and emitting light having the first wavelength. a second light emitting element that emits a second light having a second wavelength different from the second light emitting element; and an optical element that emits emitted light from the other end in accordance with the light intensity of the first light emitting element. A first photoelectric conversion element for outputting a current and a surface of the second light emitting element opposite to the surface facing the optical element are arranged to face each other, and the second light emitting element outputs a current corresponding to the light amount of the second light. The second photoelectric conversion element is disposed between the first light emitting element and the first photoelectric conversion element and the second light emitting element and the second photoelectric conversion element to prevent the first light from entering the second photoelectric conversion element. and a first shielding wall for preventing the second light from entering the first photoelectric conversion element.

Further, the optical device according to the present invention includes: a first side plate portion; a second side plate portion arranged to face the first side plate portion; a third side plate portion connecting the first side plate portion and the second side plate portion; a fourth side plate portion arranged to face the third side plate portion; and an upper plate portion arranged to cover the first side plate portion, the second side plate portion, the third side plate portion, and the fourth side plate portion; The housing further includes a housing having a concave portion forming a housing space for housing the first light emitting element, the second light emitting element, the first photoelectric conversion element, and the second photoelectric conversion element together with the substrate. It is preferably joined to the part.

Further, in the optical device according to the present invention, the upper plate portion is lower than the position facing the first and second photoelectric conversion elements and the position facing the first and second light emitting elements. and has a reflecting surface that reflects the first light and the second light.

Further, in the optical device according to the present invention, the reflective surface is inclined from a position facing the first photoelectric conversion element and the second photoelectric conversion element toward a position facing the first light emitting element and the second light emitting element. A surface is preferred.

Further, in the optical device according to the present invention, the third wavelength different from the first wavelength and the second wavelength is arranged on the substrate side by side with the second light emitting element in a direction opposite to the first light emitting element. and a surface of the third light emitting element opposite to the surface facing the optical element, and the light amount of the third light from the third light emitting element a third photoelectric conversion element that outputs a corresponding current, and is arranged between the second light emitting element and the second photoelectric conversion element and the third light emitting element and the third photoelectric conversion element, and It is preferable to further include a third shielding wall that prevents the third light from entering the third photoelectric conversion element and prevents the third light from entering the second photoelectric conversion element.

Further, in the optical device according to the present invention, a first sub-substrate is arranged on a substrate, the first light-emitting element is mounted thereon, and the first sub-substrate supports one end of the optical element; a second sub-board on which the second light emitting element is mounted and which supports one end of the optical element; and a third sub-board on which the third light emitting element is mounted and which supports one end of the optical element. so as to be covered with a sub-board, a mount supporting the other end of the optical element, and the optical element supported by the first sub-board, the second sub-board, the third sub-board, and the mount, It is preferable to further have a temperature detection sensor mounted on the substrate.

The optical device according to the present invention can separately detect the amount of light emitted from each of the plurality of mounted light-emitting elements.

1 is a perspective view of an optical device according to a first embodiment; FIG. 2 is a perspective view of the optical device shown in FIG. 1 with the housing removed; FIG. 2 is an exploded perspective view of the optical device shown in FIG. 1; FIG. 2 is a bottom view of the optical device shown in FIG. 1; FIG. FIG. 2 is a cross-sectional view taken along line DD shown in FIG. 1; FIG. 2 is a cross-sectional view taken along line EE shown in FIG. 1; FIG. 2 is a rear view of the optical device shown in FIG. 1 with the housing removed; 2 is an enlarged side view of the optical device shown in FIG. 1; FIG. (a) is a perspective view (part 1) of the housing shown in FIG. 1, and (b) is a perspective view (part 2) of the housing shown in FIG. (a) is a perspective view of the first sub-board shown in FIG. 2, and (b) is an enlarged perspective view of a portion indicated by a dashed line A in (a). (a) is a perspective view of a second sub-board shown in FIG. 2, and (b) is an enlarged perspective view of a portion indicated by a dashed line B in (a). (a) is a perspective view of a third sub-board shown in FIG. 2, and (b) is an enlarged perspective view of a portion indicated by a dashed line C in (a). 3 is an internal block diagram of the optical element shown in FIG. 2; FIG. FIG. 10 is a diagram showing a method of manufacturing a sub-board according to a modification, in which (a) shows the first step, (b) shows the second step, (c) shows the third step, and (d) shows the second step. 4 steps are shown.

An optical device according to one aspect of the present disclosure will be described below with reference to the drawings. However, it should be noted that the technical scope of the present disclosure is not limited to those embodiments, but extends to the invention described in the claims and equivalents thereof.

(Structure and function of optical device according to embodiment)
1 is a perspective view of the optical device according to the first embodiment, FIG. 2 is a perspective view of the optical device shown in FIG. 1 with the housing removed, and FIG. 3 is an exploded perspective view of the optical device shown in FIG. , and FIG. 4 is a bottom view of the optical device shown in FIG. 5 is a cross-sectional view along line DD shown in FIG. 1, FIG. 6 is a cross-sectional view along line EE shown in FIG. 1, and FIG. 7 is a cross-sectional view of the optical device shown in FIG. 8 is an enlarged side view of the optical device shown in FIG. 1. FIG.

The optical device 1 includes a first substrate 2, a second substrate 3, a housing 4, a first photodiode 5, a second photodiode 6, a third photodiode 7, a first Zener diode 8, It has a second Zener diode 9 and a third Zener diode 10 . Further, the optical device 1 includes a first sub-substrate 11, a second sub-substrate 12, a third sub-substrate 13, a first light emitting element 14, a second light emitting element 15, a third light emitting element 16, an optical It further comprises an element 17 , a pedestal 18 , a lens 19 and a thermistor 20 . The optical device 1 emits white light in response to application of a predetermined voltage from the outside.

The first substrate 2 and the second substrate 3 are made of a material having high rigidity and heat dissipation, such as aluminum nitride. The first substrate 2 has a rectangular planar shape and forms the bottom surface of the optical device 1 . A second substrate 3 is arranged on the front surface of the first substrate 2, and a plurality of electrodes for electrically connecting a controller for controlling the optical device 1 and the optical device 1 on the rear surface of the first substrate 2. pairs are placed. The electrode pairs arranged on the back surface of the first substrate 2 include electrode pairs 2r1, 2g1 and 2b1 connected to the anode and cathode of the first photodiode 5, the second photodiode 6, and the third photodiode 7. . The electrode pairs arranged on the back surface of the first substrate 2 are electrode pairs 2r2, 2g2 and 2b2 connected to the front and back electrodes of the first light emitting element 14, the second light emitting element 15 and the third light emitting element. include. Furthermore, the electrode pairs arranged on the back surface of the first substrate 2 include an electrode pair 2 s connected to both ends of the thermistor 20 .

A bonding member 201 for bonding the first substrate 2 and the housing 4 is arranged on the outer edge of the first substrate 2 . The joining member 201 is a joining member such as a gold-tin alloy paste material that has a higher melting point than solder. Although the first substrate 2 and the second substrate 3 are separate substrates, in the optical device according to the embodiment, the first substrate 2 and the second substrate 3 may be a single substrate.

A first photodiode 5 to a third Zener diode 10, a first sub-substrate 11 to a third sub-substrate 13, a mount 18, and a thermistor 20 are mounted on the surface of the second substrate 3. FIG. The surface area other than the area where the first photodiode 5 to third Zener diode 10, first sub-board 11 to third sub-board 13, base 18 and thermistor 20 are mounted is covered with solder paste 301 as an insulating layer. will be Also, on the back surface of the second substrate 3, a bonding pattern that is bonded to the bonding pattern formed on the front surface of the first substrate 2 is formed. The bonding patterns formed on the front surface of the first substrate 2 and the back surface of the second substrate 3 are formed by a bonding member such as a gold-tin alloy paste material having a higher melting point than solder.

The housing 4 is a housing member made of a metal material such as alumina that is rigid and has high heat dissipation properties. At the same time, it forms a storage space that is highly airtight and into which impurities such as moisture and organic matter are less likely to enter. The first photodiode 5 to the thermistor 20 are accommodated in a hermetically sealed accommodation space formed by the housing 4 and the first substrate 2 .

A circular emission hole 401 through which white light is emitted is formed in one side plate portion in the longitudinal direction of the housing 4 . A light-transmitting sheet 402 formed of a light-transmitting material such as glass and sealing the housing space is arranged on one side plate portion of the housing 4 in the longitudinal direction so as to cover the emission hole 401 .

9A is a perspective view of the housing 4 (Part 1), and FIG. 9B is a perspective view of the housing 4 (Part 2).

The housing 4 has a first side plate portion 411 , a second side plate portion 412 , a third side plate portion 413 , a fourth side plate portion 414 and an upper plate portion 415 . The housing 4 is formed with a concave portion 416 forming an accommodation space for accommodating the first photodiode 5 to the thermistor 20 together with the first substrate 2 and the second substrate 3 .

The first side plate portion 411 has a rectangular shape and is arranged at the longitudinal end portion of the upper plate portion 415 so that when the housing 4 is bonded to the first substrate 2 and the second substrate 3, the first side plate portion 411 has a rectangular shape. It is arranged near the first photodiode 5 to the third photodiode 7 . The second side plate portion 412 has the same shape as the first side plate portion 411, and is arranged at the end opposite to the longitudinal end of the upper plate portion 415 where the first side plate portion 411 is arranged. 401 is formed.

The third side plate portion 413 has a rectangular shape, is arranged at an end portion in the short direction of the upper plate portion 415 , and connects the first side plate portion 411 and the second side plate portion 412 . The fourth side plate portion 414 has a rectangular shape and is arranged at the end of the upper plate portion 415 in the short direction so as to face the third side plate portion 413. The first side plate portion 411 and the second side plate portion 412.

The upper plate portion 415 has a rectangular planar shape and is arranged so as to cover the upper ends of the first side plate portion 411 to the fourth side plate portion 414 . The upper plate portion 415 has a reflecting surface 417 that reflects the first to third lights emitted from the first light emitting element 14, the second light emitting element 15, and the third light emitting element 16, respectively. The reflecting surface 417 is formed as an inclined surface arranged so that the position facing the first photodiode 5 to the third photodiode 7 is lower than the position facing the first light emitting element 14 to the third light emitting element 16. be. The reflecting surface 417 reflects the first light emitted from the first light emitting element 14 to the first photodiode 5, reflects the second light emitted from the second light emitting element 15 to the second photodiode 6, and reflects the second light emitted from the second light emitting element 15 to the second photodiode 6. 3 The third light emitted from the light emitting element 16 is reflected to the third photodiode 7 .

The housing 4 further has a first shielding wall 421 and a second shielding wall 422 that are joined to the upper plate portion 415 and integrated with the housing 4 . The first shielding wall 421 has one end in contact with the first side plate portion 411 and is arranged to extend between the first light emitting element 14 and the first photodiode 5 and the second light emitting element 15 and the second photodiode 6 . be. The first shielding wall 421 prevents the first light emitted from the first light emitting element 14 from entering the second photodiode 6, and prevents the second light emitted from the second light emitting element 15 from entering the first photodiode. It prevents the diode 5 from being incident.

The second shielding wall 422 has one end in contact with the first side plate portion 411 , and the first shielding wall 421 separates the second light emitting element 15 and the second photodiode 6 from the third light emitting element 16 and the third photodiode 7 . arranged to extend in parallel. The second shielding wall 422 prevents the second light emitted from the second light emitting element 15 from entering the third photodiode 7 and prevents the third light emitted from the third light emitting element 16 from entering the second photodiode. It prevents the light from entering the diode 6 .

The first shielding wall 421 and the second shielding wall 422 may be formed by cutting the base material of the housing 4 , and after the recess 416 is formed in the housing 4 , metal powder It may be formed by applying injection molding (Metal Injection Molding, MIM).

The first photodiode 5, the second photodiode 6, and the third photodiode 7 are photodiodes made of silicon, germanium, or the like. A first photodiode 5 , a second photodiode 6 and a third photodiode 7 are arranged at the longitudinal ends of the second substrate 3 . The first photodiode 5, the second photodiode 6, and the third photodiode 7 are bonded to a bonding pattern formed on the surface of the second substrate 3 by a bonding material having a higher melting point than solder, such as a gold-tin alloy paste material. be.

The first photodiode 5 is arranged to face the surface of the first light emitting element 14 opposite to the surface facing the optical element 17 , and outputs a current corresponding to the light amount of the first light from the first light emitting element 14 . The first photodiode 5 is arranged so that the position of the second substrate 3 in the short direction coincides with the position of the first light emitting element 14 in the short direction. The anode and cathode of the first photodiode 5 are connected to a pair of electrode pairs 2r1 formed on the rear surface of the first substrate 2 via the first substrate 2 and the second substrate 3, respectively. The first photodiode 5 detects the light emitted from the first light emitting element 14, and transmits a current corresponding to the light intensity of the detected light through a pair of electrode pairs 2r1 formed on the back surface of the first substrate 2. Output to the controller.

The second photodiode 6 is arranged to face the surface of the second light emitting element 15 opposite to the surface facing the optical element 17 , and outputs a current corresponding to the amount of the second light from the second light emitting element 15 . The second photodiode 6 is arranged so that the position of the second substrate 3 in the widthwise direction coincides with the position of the second light emitting element 15 in the widthwise direction. The anode and cathode of the second photodiode 6 are connected to a pair of electrode pairs 2g1 formed on the rear surface of the first substrate 2 via the first substrate 2 and the second substrate 3, respectively. The second photodiode 6 detects the light emitted from the second light emitting element 15, and transmits a current corresponding to the light intensity of the detected light through a pair of electrode pairs 2g1 formed on the back surface of the first substrate 2. Output to the controller.

The third photodiode 7 is arranged to face the surface of the third light emitting element 16 opposite to the surface facing the optical element 17 , and outputs current from the third light emitting element 16 according to the amount of the third light. The third photodiode 7 is arranged so that the position of the second substrate 3 in the short direction coincides with the position of the third light emitting element 16 in the short direction. The anode and cathode of the third photodiode 7 are connected to a pair of electrode pairs 2b1 formed on the rear surface of the first substrate 2 via the first substrate 2 and the second substrate 3, respectively. The third photodiode 7 detects the light emitted from the third light emitting element 16, and transmits a current corresponding to the light intensity of the detected light through a pair of electrode pairs 2b1 formed on the back surface of the first substrate 2. Output to the controller.

The first zener diode 8, the second zener diode 9, and the third zener diode 10 are overvoltage protection devices that prevent overvoltage from being applied to the first light emitting element 14, the second light emitting element 15, and the third light emitting element 16, respectively. element. A first Zener diode 8 is arranged between the first photodiode 5 and the first sub-substrate 11 . A second Zener diode 9 is arranged between the second photodiode 6 and the second sub-substrate 12 . A third Zener diode 10 is arranged between the third photodiode 7 and the third sub-substrate 13 . The first Zener diode 8, the second Zener diode 9, and the third Zener diode 10 are bonded to a bonding pattern formed on the surface of the second substrate 3 by a bonding material having a higher melting point than solder, such as a gold-tin alloy paste material. be.

The first Zener diode 8 is connected in parallel to the first light emitting element 14, and applies a breakdown current to the first light emitting element 14 when an overvoltage is likely to be applied to the first light emitting element 14. to prevent

The second Zener diode 9 is connected in parallel to the second light emitting element 15, and applies a breakdown current to the second light emitting element 15 when an overvoltage is likely to be applied to the second light emitting element 15. to prevent

The third Zener diode 10 is connected in parallel to the third light emitting element 16, and applies a breakdown current to the third light emitting element 16 when overvoltage is likely to be applied to the third light emitting element 16. to prevent

10(a) is a perspective view of the first sub-board 11, and FIG. 10(b) is an enlarged perspective view of the portion indicated by the dashed line A in FIG. 10(a).

The first sub-board 11 has a first base 21 , a first light-emitting element pattern 22 and a first optical element pattern 23 and is mounted on the second substrate 3 . The first base 21 is a substantially rectangular parallelepiped member made of silicon. The first sub-substrate 11 is bonded to the surface of the second substrate 3 by a bonding member such as a gold-tin alloy paste material having a melting point higher than that of solder.

The first light emitting element pattern 22 is bonded to the first mounting surface 24 by surface activated bonding. Also, the first light emitting element pattern 22 may be formed of a bonding material such as a gold-tin alloy paste material having a melting point higher than that of solder, and may be arranged on the first mounting surface 24 . A plurality of microbumps are formed on the surface of the first light emitting device pattern 22 . The first light emitting element pattern 22 joins the back electrode of the first light emitting element 14 to the first sub-substrate 11 by surface activated bonding.

The first optical element pattern 23 is bonded to the second mounting surface 25 by surface activated bonding. Also, the first optical element pattern 23 may be formed of a bonding member such as a gold-tin alloy paste material having a melting point higher than that of solder, and may be arranged on the second mounting surface 25 . A plurality of microbumps are formed on the surface of the first optical element pattern 23 . The first optical element pattern 23 joins the optical element 17 to the first sub-substrate 11 by surface activated bonding.

Each of the first mounting surface 24 and the second mounting surface 25 has a rectangular planar shape. The height of the first mounting surface 24 from the bottom surface of the first sub-board 11 is lower than the height of the second mounting surface 25 from the bottom surface of the first sub-board 11 . The end of the second mounting surface 25 is positioned below the tip of the first light emitting element 14 by projecting the tip of the first light emitting element 14 from the first step 26 . A first recess 27 is formed extending to the opposite end. The first optical element pattern 23 is not arranged in the first concave portion 27 .

11(a) is a perspective view of the second sub-board 12, and FIG. 11(b) is an enlarged perspective view of the portion indicated by the dashed line B in FIG. 11(a).

The second sub-board 12 has a second base 31 , a second light-emitting element pattern 32 and a second optical element pattern 33 and is mounted on the second substrate 3 . The second base 31 is a substantially rectangular parallelepiped member made of silicon. The width and height of the second base 31 are substantially the same as the width and height of the first base 21 . On the other hand, the length of the second base 31 is shorter than that of the first base 21 . The second sub-substrate 12 is bonded to the surface of the second substrate 3 by a bonding member such as a gold-tin alloy paste material having a melting point higher than that of solder.

The second light emitting element pattern 32 is bonded to the third mounting surface 34 by surface activated bonding. Also, the second light emitting element pattern 32 may be formed of a bonding material such as a gold-tin alloy paste material having a melting point higher than that of solder, and may be arranged on the third mounting surface 34 . A plurality of microbumps are formed on the surface of the second light emitting device pattern 32 . The second light emitting element pattern 32 joins the back electrode of the second light emitting element 15 to the second sub-substrate 12 by surface activated bonding.

The second optical element pattern 33 is bonded to the fourth mounting surface 35 by surface activated bonding. It is also bonded to the fourth mounting surface 35 by surface activated bonding. It may be formed of a bonding member having a melting point higher than that of solder, such as a gold-tin alloy paste material, and may be arranged on the fourth mounting surface 35 . A plurality of microbumps are formed on the surface of the second optical element pattern 33 . The second optical element pattern 33 joins the optical element 17 to the second sub-substrate 12 by surface activated bonding.

Each of the third mounting surface 34 and the fourth mounting surface 35 has a rectangular planar shape. The height of the third mounting surface 34 from the bottom surface of the second sub-board 12 is lower than the height of the fourth mounting surface 35 from the bottom surface of the second sub-board 12 . The height of the fourth mounting surface 35 from the bottom surface of the first sub-board 11 is equal to the height of the second mounting surface 25 from the bottom surface of the first sub-board 11 . The end of the fourth mounting surface 35 is positioned below the tip of the second light emitting element 15 by protruding the tip of the second light emitting element 15 from the second step 36 . A second recess 37 is formed extending to one side of the . The second optical element pattern 33 is not arranged in the second concave portion 37 .

12(a) is a perspective view of the third sub-board 13, and FIG. 12(b) is an enlarged perspective view of the portion indicated by the dashed line C in FIG. 12(a).

The third sub-board 13 has a third base 41 , a third light emitting element pattern 42 and a third optical element pattern 43 and is mounted on the second substrate 3 . The third base 41 is a substantially rectangular parallelepiped member made of silicon, and has a surface on which a fifth mounting surface 44 and a sixth mounting surface 45 are formed via a third step 46 . The third base 41 has the same shape as the second base 31 . That is, the length, width and height of the third base 41 are substantially the same as the length, width and height of the second base 31 . The third sub-substrate 13 is bonded to the surface of the second substrate 3 by a bonding member such as a gold-tin alloy paste material having a higher melting point than solder.

The third light emitting element pattern 42 is bonded to the fifth mounting surface 44 by surface activated bonding. Also, the third light emitting element pattern 42 may be formed of a bonding material such as a gold-tin alloy paste material having a melting point higher than that of solder, and may be arranged on the fifth mounting surface 44 . A plurality of microbumps are formed on the surface of the third light emitting device pattern 42 . The third light emitting element pattern 42 joins the back electrode of the third light emitting element 16 to the third sub-substrate 13 by surface activated bonding.

The third optical element pattern 43 is formed of a bonding member such as a gold-tin alloy paste material having a melting point higher than that of solder, and is arranged on the sixth mounting surface 45 . A plurality of microbumps are formed on the surface of the third optical element pattern 43 . The third optical element pattern 43 joins the third light emitting element 16 to the third sub-substrate 13 by surface activated bonding.

Each of the fifth mounting surface 44 and the sixth mounting surface 45 has a rectangular planar shape. The height of the fifth mounting surface 44 from the bottom surface of the third sub-board 13 is lower than the height of the sixth mounting surface 45 from the bottom surface of the third sub-board 13 . The height of the sixth mounting surface 45 from the bottom surface of the first sub-board 11 is equal to the height of the second mounting surface 25 and the fourth mounting surface 35 from the bottom surface of the first sub-board 11 . The end of the sixth mounting surface 45 is located below the tip of the third light emitting element 16 by protruding the tip of the third light emitting element 16 from the third step 46, and the sixth mounting surface 45 is curved to form a pair of sides in the longitudinal direction. A third recess 47 extending to one side is formed. The third optical element pattern 43 is not arranged in the third concave portion 47 .

A first step 26 formed between the first mounting surface 24 and the second mounting surface 25 of the first sub-board 11 is formed by known etching techniques including wet etching and dry etching. The second step 36 of the second sub-board 12 and the third step 46 of the third sub-board 13 are formed by a known etching technique, like the first step 26 .

The first light emitting element 14 is a laser diode formed on a gallium arsenide substrate, and a forward voltage is applied between the front surface electrode and the rear surface electrode via an electrode pair 2r2 arranged on the rear surface of the first substrate 2. It emits red light in response to being turned on. The red light emitted from the first light emitting element 14 is an example of first light having a first wavelength.

The wavelength of the red light emitted from the first light emitting element 14 is within the range between 620 nm and 750 nm, and is 640 nm in one example. The first light emitting element 14 is mounted on a first mounting surface 24 via a first light emitting element pattern 22 having microbumps formed thereon. The surface electrode of the first light emitting element 14 is connected to one of the pair of electrodes 2r2 via a bonding wire (not shown), and the back electrode of the first light emitting element 14 is connected to the pair of electrodes via the first light emitting element pattern 22. 2r2.

The second light emitting element 15 is a laser diode formed on a gallium nitride substrate, and a forward voltage is applied between the front surface electrode and the rear surface electrode via an electrode pair arranged on the rear surface of the first substrate 2. Green light is emitted accordingly. Green light emitted from the second light emitting element 15 is an example of second light having a second wavelength different from the first wavelength.

The wavelength of green light emitted from the second light emitting element 15 is within the range between 490 nm and 570 nm, and is 520 nm in one example. The second light emitting element 15 is mounted on a third mounting surface 34 via a second light emitting element pattern 32 having microbumps formed thereon. The surface electrode of the second light emitting element 15 is connected to one of the pair of electrodes 2g2 via a bonding wire (not shown), and the back electrode of the second light emitting element 15 is connected to the pair of electrodes via the second light emitting element pattern 32. 2g2.

The third light emitting element 16 is a laser diode formed on a gallium nitride substrate, and a forward voltage is applied between the front electrode and the back electrode via an electrode pair arranged on the back surface of the first substrate 2. In response, it emits blue light. The blue light emitted from the third light emitting element 16 is an example of third light having a third wavelength different from the first wavelength and the second wavelength.

The wavelength of the blue light emitted from the third light emitting element 16 is within the range between 450 nm and 495 nm, and is 455 nm in one example. The third light emitting element 16 is mounted on a fifth mounting surface 44 via a third light emitting element pattern 42 having microbumps formed thereon. The surface electrode of the third light emitting element 16 is connected to one of the pair of electrodes 2r2 via a bonding wire (not shown), and the back electrode of the third light emitting element 16 is connected to the pair of electrodes via the third light emitting element pattern 42. 2r2.

The optical element 17 is an optical multiplexer formed on a silicon substrate, such as the optical multiplexer described in Patent Document 1, for example. The optical element 17 is formed of a base material 17a made of silicon and a clad layer 17b inside which is formed a core, which is an optical waveguide through which light is guided. The optical element 17 multiplexes the red light, the green light, and the blue light emitted from each of the first to third light emitting elements 14 to 16 and emits white light. The clad layer 17b is formed on the lower surface of the base material 17a.

FIG. 13 is an internal block diagram of the optical element 17. As shown in FIG.

The optical element 17 includes a first optical waveguide 51 , a second optical waveguide 52 , a third optical waveguide 53 , a first coupler 54 , a second coupler 55 , a third coupler 56 , and a phase controller 57 . have. The first optical waveguide 51, the second optical waveguide 52, the third optical waveguide 53, the first coupler 54, the second coupler 55, the third coupler 56, and the phase control section 57 are formed inside the clad layer 17b made of silicon oxide. is a core formed in Projections are formed below the first optical waveguide 51 , the second optical waveguide 52 and the third optical waveguide 53 . The convex portions formed below the first optical waveguide 51, the second optical waveguide 52, and the third optical waveguide 53 are inserted into the first concave portion 27, the second concave portion 37, and the third concave portion 47, respectively.

The first optical waveguide 51 is arranged such that a first incident port 51a at one end faces the output surface of the first light emitting element 14, and red light is incident from the first light emitting element 14 via the first incident port 51a. . The second optical waveguide 52 is arranged such that the second incident port 52a at one end faces the output surface of the second light emitting element 15, and the green light is incident from the second light emitting element 15 via the second incident port 52a. . The third optical waveguide 53 is arranged such that a third incident port 53a at one end faces the output surface of the third light emitting element 16, and blue light is incident from the third light emitting element 16 via the third incident port 53a. .

The first coupler 54 is, for example, a 3 dB coupler, and multiplexes the green light incident via the second optical waveguide 52 and the blue light incident via the third optical waveguide 53 and outputs the resultant to the second coupler 55 . At the same time, blue light is emitted to the phase control section 57 . The second coupler 55 is, for example, a 3 dB coupler, and multiplexes the combined light of the red light incident through the first optical waveguide 51 and the green light and blue light incident from the first coupler 54 , and the third coupler 56 to The third coupler 56 is, for example, a 3 dB coupler, and combines the combined light incident via the second coupler 55 and the blue light incident via the phase control unit 57 to generate white light, and generates white light. The light is emitted from the emission port 52b to the lens 19 as emitted light.

The mount 18 is made of alumina, supports the other end of the optical element 17 and holds the lens 19 . The bottom surface of the pedestal 18 is joined to the joint pattern formed on the surface of the second substrate 3 by a joint member such as a gold-tin alloy paste material having a higher melting point than solder. The upper surface of the pedestal 18 is joined to the optical element 17 by a joining member such as a gold-tin alloy paste material having a higher melting point than solder.

The lens 19 is a convex lens made of a light-transmitting member such as glass, and is held by the pedestal 18 by being arranged inside a through hole formed in the pedestal 18 . The lens 19 is arranged such that the end face on the optical element 17 side is located inside the opening of the through hole on the optical element 17 side. The space between the opening of the through hole and the end surface of the lens 19 functions as a diaphragm that adjusts the amount of light emitted from the output port 52b of the optical element 17. FIG. The lens 19 collimates the diameter of the emitted light that enters while diverging from the emission port 52 b of the optical element 17 to generate output light that is parallel light. emitted to the outside of

The thermistor 20 is a temperature detection sensor mounted on the second substrate 3 so as to be covered with the optical element 17 supported by the first sub-substrate 11, the second sub-substrate 12, the third sub-substrate 13, and the pedestal 18. be. The thermistor 20 is arranged below the optical element 17 . The thermistor 20 changes its resistance value according to the temperature change in the accommodation space formed by the first substrate and the housing 4 . Both ends of the thermistor 20 are connected to a pair of electrode pairs 2 s formed on the back surface of the first substrate 2 via the first substrate 2 and the second substrate 3 . The thermistor 20 outputs a voltage value or a current value corresponding to a resistance value indicating the temperature of the accommodation space to the control device via a pair of electrode pairs 2 s formed on the back surface of the first substrate 2 .

(Effects of the optical device according to the embodiment)
In the optical device 1, the first mounting is arranged via the first step 26 formed so that the height of the emission surface of the first light emitting element 14 and the height of the first optical waveguide 51 of the optical element 17 match. The first light emitting element 14 and the optical element 17 are mounted on the surface 24 and the second mounting surface 25, respectively. In the optical device 1 , the heights of the first light emitting element 14 and the optical element 17 are adjusted via the first step 26 . 51 height can be easily matched. In the optical device 1, the height of the output surface of the first light emitting element 14 can be easily matched with the height of the first optical waveguide 51 of the optical element 17. Therefore, the manufacturing cost is increased and the radiation characteristics are lowered without using a spacer. High-precision alignment can be achieved by the passive alignment method without incurring any problems.

Similarly, since the heights of the second light emitting element 15 and the optical element 17 are adjusted via the second step 36, the height of the output surface of the second light emitting element 15 is adjusted to the height of the second optical waveguide 52 of the optical element 17. Can be easily matched in height. Further, since the heights of the third light emitting element 16 and the optical element 17 are adjusted via the third step 46, the height of the output surface of the third light emitting element 16 is adjusted to the height of the third optical waveguide 53 of the optical element 17. can be easily matched.

In the optical device 1, the first light emitting element 14 to the third light emitting element 16 and the optical element 17 are formed on the surfaces of the first sub-substrate 11 to the third sub-substrate 13 with microbumps whose thickness can be finely adjusted. surface-activated bonding to the pattern. In the optical device 1, variations in core heights of the first light-emitting element 14 to the optical element 17 due to manufacturing conditions can be absorbed by surface-activated bonding of a pattern having microbumps formed on the surface.

In the optical device 1, only the first light enters the first photodiode 5, only the second light enters the second photodiode 6, and the third Only light enters the third photodiode 7 . In the optical device 1, each of the first photodiode 5 to the third photodiode 7 receives only one of the first light to the third light emitted from the first light emitting element 14 to the third light emitting element 16. Therefore, the first to third lights can be detected separately. Since the optical device 1 separately detects the first to third lights emitted from the first to third light emitting elements 14 to 16, light is incident from other light emitting elements and emitted from each of the light emitting elements. There is little possibility that the detection accuracy of the amount of light that is applied is lowered.

Further, in the optical device 1, the first shielding wall 421 and the second shielding wall 422 are integrated with the housing 4, so that the manufacturing cost can be reduced by installing the shielding walls without increasing the number of parts. It is possible to detect the amount of light emitted from the light emitting element with high accuracy while suppressing it. In the optical device 1, since the first shielding wall 421 and the second shielding wall 422 are integrated with the housing 4, the space for arranging the first shielding wall 421 and the second shielding wall 422 is provided on the second substrate. 3 is not formed, the area of the second substrate 3 is reduced, and miniaturization is possible.

In addition, in the optical device 1, the reflecting surface 417 reflects the first to fourth lights to the first to third photodiodes 5 to 7, respectively. a lot of light can be incident on the In the optical device 1, by allowing more light to enter the first photodiode 5 to the third photodiode 7, it is possible to further improve the detection accuracy of the amount of light emitted from the light emitting element.

Further, since the thermistor 20 is arranged below the optical element 17, the optical device 1 can be miniaturized by reducing the areas of the first substrate 2 and the second substrate 3. FIG. Further, in the optical device 1, the thermistor 20 is arranged below the optical element 17, so that the first to third lights emitted from the first to third light emitting elements 14 to 16 are incident and the characteristics are changed. deterioration can be prevented.

(Modified example of the optical device according to the embodiment)
The optical device 1 has first to third light emitting elements 14 to 16 that respectively emit red light, green light, and blue light, but the optical device according to the embodiment has only a single light emitting element. may Also, the optical device according to the embodiment may have two or four or more light emitting elements.

In the optical device 1, the first light emitting element 14 to the third light emitting element 16 are mounted on the first sub-board 11 to the third sub-board 13, respectively. 14 to third light emitting elements 16 may be mounted on a single sub-board. Further, in the optical device according to the embodiment, the first light emitting element 14 is mounted on the first sub-substrate 11, and the second light emitting element 15 and the third light emitting element 16 having the same size are mounted on a single sub-substrate. MAY be implemented.

In the optical device 1, the mounting surface on which the first light emitting element 14 to the third light emitting element 16 are mounted is higher than the mounting surface on which the optical element 17 is mounted. less than the height from However, in the optical device according to the embodiment, the height of the mounting surface on which the plurality of light emitting elements are mounted from the bottom surface of the sub-board is higher than the height from the bottom surface of the sub-board on which the optical elements are mounted. It can be expensive.

Further, in the optical device 1, the first light emitting element 14 to the third light emitting element 16 and the optical element 17 are mounted by surface activation bonding to a pattern having finely adjustable microbumps formed on the surface. However, in the optical device according to the embodiment, the first light-emitting element 14 to the third light-emitting element 16 and the optical element 17 need only be bonded by a bonding member having a melting point higher than that of solder without using surface activated bonding.

Also, in the optical device 1, the optical element 17 is an optical multiplexer, but in the optical device according to the embodiment, the optical element may have an optical waveguide, such as a filtering element, a lens element and a polarizing element. It may be an optical element other than an optical multiplexer such as.

In the optical device 1, the first sub-substrate 11, the second sub-substrate 12, and the third sub-substrate 13 are formed of silicon substrates. Insulator) may be formed by a substrate.

In the optical device 1, the first step 26, the second step 36 and the third step 46 are formed by etching the surfaces of the first sub-substrate 11, the second sub-substrate 12 and the third sub-substrate 13. . However, in the optical device according to the embodiment, the step may be formed by etching the substrate on which the etch stopper layer is formed.

14A and 14B are diagrams showing a method of manufacturing a sub-board according to a modification, in which FIG. 14A shows the first step, FIG. 14B shows the second step, and FIG. 14C shows the third step. 14(d) shows the fourth step.

First, in the first step, the base material 60 is prepared. The substrate 60 has a base 61 , an etch stopper layer 62 and an upper layer 63 . The base 61 is a silicon substrate, the etch stopper layer 62 is a silicon oxide layer formed on the surface of the base 61 , and the upper layer 63 is a silicon layer formed on the surface of the etch stopper layer 62 .

Next, in a second step, a first mounting surface having a low height from the bottom surface of the base material 60 is formed without covering the surface on which the first mounting surface having a low height from the bottom surface of the base material 60 is formed. A mask 64 is placed to cover the surface to be exposed.

Next, in a third step, an etching process is performed to form the first mounting surface 66 and the second mounting surface 67 with the step 68 therebetween, thereby manufacturing the sub-board 69 . In the sub-substrate 69, the surface of the etch stopper layer 62 forms a first mounting surface and the surface of the upper layer 63 forms a second mounting surface. Then, in the fourth step, the mask 64 is removed and the manufacturing process of the sub-board 69 is completed.

Since the sub-board 69 according to the modification is formed from the base material 60 having the etch stopper layer 62 whose surface is the surface of the first mounting surface 66 , the gap between the first mounting surface 66 and the second mounting surface 67 is The height can be formed with higher precision.

Also, in the optical device 1, the housing 4 is made of a metal material, but in the optical device according to the embodiment, the housing may be made of a ceramic material. When the housing is made of a ceramic material, a metal plating layer is arranged in the concave portion of the housing including the reflective surface, the first shielding wall and the second shielding wall.

Further, in the optical device 1, the reflecting surface 417 is formed as an inclined surface, but in the optical device according to the embodiment, the reflecting surface formed on the upper plate portion of the housing is a curved surface including a spherical surface. good too.

In the optical device 1, the first to third Zener diodes 8 to 10 are arranged between the first to third light emitting elements 14 to 16 and the first to third photodiodes 5 to 7, respectively. However, in the optical device according to the embodiment, the first Zener diode 8 to the third Zener diode 10 may be arranged below the optical element 17 like the thermistor 20 . By arranging the first to third Zener diodes 8 to 10 below the optical element 17, the optical device according to the embodiment can be further miniaturized.

REFERENCE SIGNS LIST 1 optical device 2 first substrate 3 second substrate 4 housing 14 first light emitting element 15 second light emitting element 16 third light emitting element

Claims (6)

a substrate;
a first light emitting element mounted on the substrate and emitting a first light having a first wavelength;
a second light emitting element arranged on the substrate alongside the first light emitting element and emitting a second light having a second wavelength different from the first wavelength;
an optical element arranged so that one end faces the first light emitting element and the second light emitting element, and emitting emitted light from the other end in response to light incident from the first light emitting element;
a first photoelectric conversion element arranged to face the surface of the first light emitting element opposite to the surface facing the optical element, the first photoelectric conversion element outputting a current corresponding to the light amount of the first light from the first light emitting element;
a second photoelectric conversion element arranged to face the surface of the second light emitting element opposite to the surface facing the optical element, the second photoelectric conversion element outputting a current according to the light amount of the second light from the second light emitting element;
It is arranged between the first light emitting element and the first photoelectric conversion element and the second light emitting element and the second photoelectric conversion element, and prevents the first light from entering the second photoelectric conversion element. a first shielding wall for preventing the second light from entering the first photoelectric conversion element;
An optical device characterized by comprising: a first side plate portion; a second side plate portion arranged to face the first side plate portion; a third side plate portion connecting the first side plate portion and the second side plate portion; and an upper plate portion arranged to cover the first side plate portion, the second side plate portion, the third side plate portion and the fourth side plate portion, the first further comprising a housing formed with a concave portion forming a housing space for housing the light emitting element, the second light emitting element, the first photoelectric conversion element, and the second photoelectric conversion element together with the substrate;
2. The optical device according to claim 1, wherein said first shielding wall is bonded to said upper plate portion. The upper plate portion is formed to be lower than a position facing the first photoelectric conversion element and the second photoelectric conversion element and a position facing the first light emitting element and the second light emitting element, 3. The optical device according to claim 2, comprising a reflective surface that reflects the first light and the second light. 3. The reflecting surface is an inclined surface that is inclined from a position facing the first photoelectric conversion element and the second photoelectric conversion element toward a position facing the first light emitting element and the second light emitting element. 4. The optical device according to 3. A third light emitting element is arranged on the substrate side by side with the second light emitting element in a direction opposite to the first light emitting element, and emits a third light having a third wavelength different from the first wavelength and the second wavelength. 3 light emitting elements;
a third photoelectric conversion element arranged to face the surface of the third light emitting element opposite to the surface facing the optical element, the third photoelectric conversion element outputting a current according to the light amount of the third light from the third light emitting element;
It is arranged between the second light emitting element and the second photoelectric conversion element and the third light emitting element and the third photoelectric conversion element, and prevents the second light from entering the third photoelectric conversion element. a third shielding wall for preventing the third light from entering the second photoelectric conversion element;
The optical device according to any one of claims 1 to 4, further comprising: a first sub-substrate arranged on the substrate, on which the first light-emitting element is mounted, and which supports one end of the optical element;
a second sub-substrate arranged on the substrate alongside the first sub-substrate, on which the second light-emitting element is mounted, and which supports one end of the optical element;
a third sub-board on which the third light emitting element is mounted and which supports one end of the optical element;
a mount supporting the other end of the optical element;
a temperature detection sensor mounted on the substrate so as to be covered by the optical element supported by the first sub-substrate, the second sub-substrate, the third sub-substrate, and the pedestal;
6. The optical device of claim 5, further comprising:

Images