JP2004241415A - Optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical device in which operating characteristics of a semiconductor light emitting element, e.g. a semiconductor laser diode (LD), are improved while saving a space. <P>SOLUTION: A plurality of substrates (a first substrate 9, a second substrate 10, a third substrate 11) mounting an optical unit 5 comprising a semiconductor laser element (LD) 14, a collimator lens 5a, anamorphic prisms 5b and 5c, a beam splitter 7, and a photodiode 8, and electronic components for controlling the operation of the semiconductor light emitting element are fixed to a case 30. The plurality of substrates 9, 10 and 11 are arranged in the case 30 while being stacked and the dimension Lb in the longitudinal direction of the case is shortened as compared with a case where all electronic components are mounted on one substrate in multistage. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an optical device that saves space and improves the operating characteristics of a semiconductor light emitting device such as a semiconductor laser device (LD).
[0002]
[Prior art]
A semiconductor laser element (hereinafter abbreviated as LD) emits light when a pulse-like voltage formed by a switching circuit is applied. FIG. 14 is a circuit diagram showing an example of an LD drive circuit described in Patent Document 1. 14, the LD drive circuit includes a constant current circuit 101, a switching circuit 102, an amplifier circuit 103, and a CPU 110 as a control circuit.
[0003]
The constant current circuit 101 is a voltage-current converter, and flows a current I1 corresponding to the light amount signal 104 from the control circuit 110. The switching circuit 102 switches the current I1 with the laser lighting signal 105. The LD 106 emits light in response to the operation of the switching circuit 102 driven by the laser lighting signal 105. The amount of light emitted from the LD 106 is extracted as a change in the current value of a photodiode (hereinafter abbreviated as PD) 107 and is converted into a voltage signal by a resistor 108.
[0004]
The light emission amount extracted as a voltage signal is amplified by the amplifier circuit 103, and a light emission amount signal 109 is formed. The control circuit 110 increases the level of the light quantity signal 104 while monitoring the light emission quantity signal 109 until the light quantity reaches the specified light quantity. In this way, the drive control of the LD 106 is performed. As described above, the drive circuit of the LD includes the control circuit using the CPU (microcomputer, microcomputer) 110, and many electronic components are mounted on the circuit board.
[0005]
FIG. 15 is a schematic vertical sectional side view showing an example in which such an LD drive circuit and a control circuit using a microcomputer are mounted on the same circuit board. FIG. 15 is not described in Patent Document 1. In FIG. 15, an optical device 51 is housed in a case 50. 52 is a support plate (bottom plate), 53a and 53b are frames of the case 50, and 54 is a cover. Further, 52a is a heat transfer plate, and 56 is a mounting plate for the optical unit 55.
[0006]
The optical unit 55 includes an LD 59, a collimator lens for guiding the light emitted from the LD 59 to the beam splitter 57, an anamorphic prism, and a PD 58. CL is the optical axis of the light emitted from the LD 59. The emitted light of the LD 59 branched by the beam splitter 57 is detected by the PD 58 and used when performing optical output control by APC (Automatic Power Control). Although not shown, a temperature adjustment circuit (TEC) for adjusting the temperature of the LD is externally attached to the case 50.
[0007]
[Patent Document 1]
JP-A-10-119350
[0008]
[Problems to be solved by the invention]
Thus, in the example of FIG. 15, the LD drive circuit and the control circuit using the microcomputer are mounted on the same circuit board 60. For this reason, the circuit board becomes large, and the dimension La in the longitudinal direction of the case 50 becomes long. Therefore, there is a problem that space cannot be saved. Further, if the LD 59 and the LD drive circuit are placed apart from each other, the operating characteristics of the LD deteriorate, such as being affected by noise and deteriorating the rising and falling characteristics when a pulse voltage is applied to the LD. There was a problem of becoming. Furthermore, since the temperature adjustment circuit is externally attached to the case, there is a problem that the pace cannot be saved in this regard.
[0009]
The present invention has been made in view of the above-described problems, and has as its object to provide an optical device that saves space and improves the operating characteristics of a semiconductor laser diode (LD).
[0010]
[Means for Solving the Problems]
In order to achieve the above object, an optical device according to the present invention includes, in a case, a semiconductor light emitting element, an optical unit including a plurality of optical elements in front of light emitted from the semiconductor light emitting element, and a semiconductor light emitting element. An optical device for mounting a plurality of substrates on each of which electronic components for controlling operations are mounted, wherein the plurality of substrates are stacked and arranged in multiple stages. For this reason, the space in which the optical device is installed can be saved by reducing the size of the case in the longitudinal direction. Therefore, the space around the outer periphery of the case can be effectively used for installation of other devices.
[0011]
Further, the optical device according to the present invention is characterized in that the optical unit has at least means for branching light emitted from the semiconductor light emitting element, and means for detecting the branched light. For this reason, APC of the semiconductor light emitting device can be performed by detecting the branched light.
[0012]
Further, in the optical device of the present invention, in the multi-staged substrate, a substrate for a temperature adjustment circuit of the semiconductor light emitting element (first substrate) may be provided on a surface of a case in a direction of discharging heat generated by the semiconductor light emitting element. ) Is arranged. As described above, since the first substrate is disposed on the case surface on the heat-dissipation side, the electronic components mounted on the first substrate (the substrate for the temperature adjustment circuit) consume a large amount of electric power. The generated heat can be easily discharged because the heat transfer path between the first substrate and the heat discharge surface is short and there is no obstacle in the heat transfer path.
[0013]
Further, the optical device of the present invention may be arranged such that the semiconductor light-emitting element is provided on the substrate arranged in multiple stages, in the same plane as the optical axis direction of the light emitted from the semiconductor light-emitting element, and at a position close to the semiconductor light-emitting element. The driving circuit substrate (second substrate) is disposed. For this reason, the length of the signal line connecting the semiconductor light emitting element and the driving circuit is shortened, and the rising and falling characteristics of the pulse signal applied from the driving circuit to the semiconductor light emitting element can be improved. Operating characteristics can be improved.
[0014]
Further, in the optical device of the present invention, in the multi-layered substrate, the control circuit substrate (third substrate) of the semiconductor light emitting element may be arranged such that the control circuit substrate (third substrate) is configured to discharge heat generated by the semiconductor light emitting element from a surface of the case. It is characterized by being arranged at the farthest position. For this reason, it is possible to effectively use the space in the case that is separated from the heat discharge direction where there is a relatively large space.
[0015]
Further, the optical device of the present invention is characterized in that the second substrate and the third substrate have electronic components mounted on both front and back surfaces. Therefore, the size of the second substrate and the size of the third substrate can be reduced, and the size of the optical device can be reduced.
[0016]
The optical device according to the present invention is characterized in that the third substrate is disposed so as to cover the semiconductor light emitting element and the optical unit. For this reason, the semiconductor light emitting element and the optical unit are prevented from being damaged by dropping parts and the like, and safety is improved. Further, it is possible to prevent the light emitted from the semiconductor light emitting element from leaking out of the case from an unnecessary direction.
[0017]
The optical device according to the present invention is characterized in that an opening is formed at one end of the third substrate at a position corresponding to the means for detecting the split light. For this reason, it is possible to easily adjust the position of the branching light detecting means and perform wiring processing from the detecting means to the APC.
[0018]
The optical device according to the present invention is characterized in that the third substrate is provided with an empty space for mounting an additional electronic component. For this reason, it is possible to add storage means for storing image data, and the use of the optical device can be expanded.
[0019]
The third substrate is covered with a cover plate having a substantially gate-shaped cross section with an open surface corresponding to at least the side on which the semiconductor light emitting element and the optical unit are arranged, and the cover plate has a thickness greater than that of the third substrate. A slit is formed on the side surface on the tip side. For this reason, the leakage light from the semiconductor light emitting element is prevented from doubly leaking, so that the emission light from the semiconductor light emitting element can be reliably prevented from leaking out of the case from an unnecessary direction.
[0020]
Further, in the optical device of the present invention, four first support members having substantially equal lengths are fixed in a rectangular shape on the surface of the case in a direction in which heat generated by the semiconductor light emitting element is exhausted, The second substrate is fixed by the two first support members in the above, and the second support member for fixing the third substrate is in the two first support members in the remaining diagonal positions. It is characterized by being connected. As described above, of the four support members fixed to the support plate, two at the diagonal positions fix the second substrate, and the other two support members at the diagonal positions correspond to the third substrate. It functions as a connecting means of the fixing support member. Therefore, the four support members can be effectively used for different uses of the fixing means of the second substrate and the connecting means. Further, since a small number of support members are required to support the third substrate, the cost can be reduced.
[0021]
Further, the optical device of the present invention is mounted on each of the first substrate, the second substrate, and the third substrate on the surface of the case on the side where one end of the third substrate is commonly fixed. An opening is provided to collectively connect cables connected to the electronic components to the outside. As described above, the cable is taken out from the opening on the surface on which the substrates are fixed in common, that is, the surface on the opposite side to the traveling direction of the emitted light of the semiconductor light emitting element. For this reason, the wiring process at the time of connecting each cable to the electronic components mounted on the board is not complicated, and the maintenance and inspection of the cable can be easily performed.
[0022]
In the optical device according to the present invention, the semiconductor light emitting device is a semiconductor laser device. Therefore, especially when a semiconductor laser element is used as a light source of the optical device, the characteristics of the pulse voltage applied to the semiconductor laser element can be improved. Further, it is possible to save an installation space for an optical device using a semiconductor laser element as a light emitting element.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings. In the basic configuration of the present invention, a circuit board on which various electronic components necessary for operating a semiconductor laser device (LD) are mounted is divided into a plurality of boards, and each circuit board is arranged and attached in multiple stages in a case. This saves space. The circuit board for the LD drive circuit is attached to the case in the same plane (horizontal plane) as the optical axis of the LD and close to the LD, thereby improving the operating characteristics of the LD.
[0024]
FIG. 1 is a schematic vertical sectional side view showing a configuration example of an optical device to which the present invention is applied. In FIG. 1, an optical unit 5, a first substrate 9, a second substrate 10, and a third substrate 11 are arranged in a case 30 in a multi-tiered manner. 2 is a support plate (bottom plate) of the case 30, 3a is a front panel of the case 30, 3b is a rear panel of the case 30, and 4 is a cover. The components on the outer periphery of the case 30 are formed by sheet metal processing of a metal plate or resin molding.
[0025]
The optical unit 5 is disposed in front of the direction in which light emitted from the semiconductor laser element (LD) 14 held by the holder 15 travels. The optical unit 5 includes a collimator lens 5a, anamorphic prisms 5b and 5c, a beam splitter 7, and a photodiode (PD) 8. The PD 8 is fixed to the support 8a (FIG. 2). CL is the optical axis of the light emitted from the LD 14. An optical unit 5 composed of these optical elements is fixed to a mounting plate 6. Further, a Peltier element and a thermistor (not shown) are provided in the mounting plate 6.
[0026]
Reference numeral 9 denotes a first substrate on which a temperature adjustment circuit (TEC) for adjusting the temperature of the LD 14 is mounted, which is mounted on the support plate 2 of the case 30. The temperature adjustment circuit is connected to a Peltier device and a thermistor provided in the mounting plate 6 and electronically controls the temperature of the LD 14. The first substrate 9 may be mounted on a heat-dissipating block (heat sink) instead of directly on the support plate 2. In this case, the heat-dissipating block is made of a metal having good thermal conductivity, such as copper or aluminum.
[0027]
Further, in the present invention, as shown in FIG. 1, the first substrate 9 on which the temperature adjustment circuit (TEC) is mounted is placed on the support plate 2 of the case 30 (the surface on the side of discharging the heat generated by the LD 14). Above). For this reason, the heat-dissipation area increases, and heat generated when large electric power is consumed during the operation of the electronic components mounted on the temperature adjustment circuit board can be effectively discharged. Further, since the heat transfer path between the first substrate 9 and the heat discharge surface is short, and there is no obstacle in the heat transfer path, heat can be easily discharged.
[0028]
Reference numeral 10 denotes a second substrate on which a drive circuit of the semiconductor laser element (LD) 14 is mounted, and is mounted on the first substrate 9 so as to overlap. In this drive circuit, various electronic components such as a pulse generation circuit formed of an IC are mounted. The second substrate 10 is attached in the same plane as the direction of the optical axis CL of the LD 14, in this example, on a horizontal plane. Reference numerals 12 and 13 are support members for the second substrate 10 and the third substrate 11, respectively.
[0029]
The support member 12 includes a spacer (FIG. 8) provided along an end of the case, a support leg and a support piece (FIG. 11), and holds one end of the second substrate 10 and the third substrate 11. . Similarly to the support member 12, the support member 13 includes spacers (FIG. 8) erected on both side surfaces of the case and support legs and support pieces (FIG. 11). Details of the support members 12 and 13 will be described later with reference to FIGS. The second substrate 10 has electronic components 10a and 10b mounted on both sides. As described above, since the second substrate 10 is disposed so as to overlap the first substrate 9, the space in the case 30 can be effectively used.
[0030]
The second substrate 10 on which the drive circuit of the LD 14 is mounted is provided in the case 30 at a position close to the LD 14, for example, at a distance of about several mm to several tens of mm in the same plane as the direction of the optical axis CL of the LD 14. I have. Therefore, the length of the signal line connecting the LD 14 and the drive circuit is shortened, and the rising and falling characteristics are improved when a pulse voltage is applied from the drive circuit to the LD 14. That is, the operating characteristics of the LD 14 are improved. Note that the shortened length of the signal line makes the drive circuit less susceptible to external noise.
[0031]
Reference numeral 11 denotes a third substrate on which a control circuit (controller circuit) having an information processing unit such as a microcomputer is mounted. The controller circuit is connected to an external computer, receives a command signal such as a beam pattern from the computer, and temporarily stores the command signal in a storage unit such as a buffer memory. As described above, since the means for storing the command signal such as the intensity of the beam pattern from the computer is provided, the LD 14 can be operated accurately and quickly.
[0032]
The third substrate 11 is provided above the second substrate 10, that is, at a position of a space farthest from the support plate 2 in the heat exhaust direction among a plurality of substrates arranged in multiple stages. Are placed. For this reason, the space in the case can be effectively used. Electronic components 11a to 11c are mounted on both the front and back surfaces of the third substrate 11. As described above, since the first substrate 9, the second substrate 10, and the third substrate 11 are arranged in a multi-tiered manner in the case 30, the internal space of the case 30 can be three-dimensionally used. . Therefore, the length Lb of the case 30 in the longitudinal direction is reduced to about half the length La of the case using one conventional circuit board shown in FIG. Space can be effectively used.
[0033]
In FIG. 1, the other end of the third substrate 11, which is not supported by the support member 12, is also supported by a support member of the rear panel 3a (not shown) (see FIG. 7). Further, since the third substrate 11 is disposed so as to cover the upper part of the optical unit 5, it prevents the light emitted from the LD 14 from leaking in an unnecessary direction above the case 30. For this reason, it is possible to prevent the occurrence of a situation such as causing an erroneous operation by optically affecting other components. In addition, the third substrate 11 prevents other components from falling or coming into contact with an operator, thereby ensuring the safety of the LD 14 and each optical element of the optical unit 5.
[0034]
As described above, since the third substrate 11 is sized to cover the upper part of the optical unit 5, the length in the longitudinal direction is longer than that of the first substrate 9 and the second substrate 10, and the area is set to be larger. it can. For this reason, it is possible to increase the free space in which the electronic components are not mounted, and to additionally mount a storage unit such as a RAM as needed. When the controller circuit is connected to an external computer and is operated according to a command from the external computer, the storage circuit is additionally provided and can be used as a buffer for temporarily storing photographs and other read originals. Therefore, the use of the optical device can be expanded, for example, by using the LD 14 as an exposure light source of an image forming apparatus.
[0035]
FIG. 2 is a longitudinal sectional side view showing the optical unit 5 in a partially enlarged manner. The light emitted from the LD 14 is converted into a parallel light by the collimator lens 5a. Since the beam emitted from the LD 14 has an elliptical shape, anamorphic prisms 5b and 5c are arranged in front of the collimator lens 5a for the purpose of shaping the beam into a perfect circle. By adjusting the positions of the anamorphic prisms 5b and 5c, the beam can be stably formed into a perfect circle regardless of the value of the aspect ratio of the LD used. Further, as described above, the beam splitter 7 and the photodiode (PD) 8 are provided for performing APC of the light source.
[0036]
FIG. 3 is an explanatory diagram of a section taken along line AA of FIG. Note that some of the electronic components shown in FIG. 1 are not shown for simplicity. 3, reference numerals 22 and 23 denote spacers for supporting the second substrate 10 and the third substrate 11, which will be described later in detail with reference to FIGS. The first substrate 9 is disposed between the spacers 22, but is not shown. The second substrate 10 is arranged in the same plane (horizontal plane) as the optical axis direction of the LD 14. A connector 29 to which a pulse input cable is connected is provided on the second substrate 10. The third substrate 11 is provided with an LED indicator 28, a connector 31 for a cable connected to a computer, and a connector 32 for a cable connected to a power supply. As is clear from FIG. 3, the first substrate 9, the second substrate 10, and the third substrate 11 are stacked and arranged in a space in the case 30.
[0037]
FIG. 4 is a rear view as viewed in the direction of arrow B in FIG. In FIG. 4, openings 17a to 17d for allowing cables to communicate with the inside of the case are formed in the rear panel 3b. Further, a key switch 16a and an interlock 16b are provided. The key switch 16a is provided as a security measure so that only a specific user can operate the optical device. Further, the interlock 16b electrically cuts off the cable so that the electronic component does not break down when a failure occurs in the power supply system or the like. The opening 17a communicates a cable connected to the connector 29 mounted on the second board 10. The opening 17b communicates a cable connected to the LED display 28 mounted on the third board. The openings 17c and 17d communicate with a computer connection cable and a power supply cable connected to the connectors 31 and 32 provided on the third board 11, respectively.
[0038]
As described above, the opening that allows the cables to communicate collectively with the inside and outside of the case is provided on the rear side of the case, that is, on the side where one end of each substrate is fixed in common. Therefore, the wiring process for connecting each cable to the electronic components mounted on the board is not complicated, and the maintenance and inspection of the cable can be easily performed.
[0039]
FIG. 5 is a plan view illustrating an example of the second substrate 10. Although an appropriate number of electronic components 10a forming an LD drive circuit are mounted on the surface of the second substrate 10 (FIG. 1), only the terminal block 29 is shown for simplicity. At four circumferential ends of the second substrate 10, mounting holes (screw holes) 10p to 10s for supporting members (spacers) are formed. Note that, as shown in FIGS. 11 and 12, a support piece for fixing the second substrate 10 and the third substrate 11 with screws may be formed on the support members 12 and 13.
[0040]
FIG. 6 is a plan view illustrating an example of the third substrate 11. Although an appropriate number of electronic components forming a microcomputer control circuit are mounted on the surface of the third substrate 11, only the LED display 28 and the terminal blocks 31 and 32 described in FIG. Is shown. On one end side of the third substrate 11, mounting holes (screw holes) 11p and 11s for supporting members (spacers) are formed. Further, mounting holes (screw holes) 11u and 11v for the support member (front panel) are formed at the other end of the third substrate 11.
[0041]
On the surface of the third substrate 11, a space of an empty area where no electronic component is mounted is formed, and it is possible to cope with an increase in RAM and the like. The notch 11y formed at one end of the third substrate 11 corresponds to the position of the PD 8 in FIG. 1, and the position adjustment of the PD 8 and the wiring process from the PD 8 to the APC are easy. Can be done.
[0042]
FIG. 7 is a schematic three-dimensional view showing a state where the second substrate 10 is attached to a case. In FIG. 7, spacers 22a to 22d are fixed to the support plate (bottom plate) 2 (22c and 22d are not shown). The first substrate 9 is mounted on the support plate 2 between the four spacers. The second substrate 10 is fixed to the spacers 22a and 22d with screws 24a and 24b. Spacers 23a and 23b are added to the spacers 22b and 22c. As described above, the second substrate 10 is fixed by only two spacers arranged at diagonal positions among the four spacers arranged in a rectangular shape. The remaining two diagonally arranged spacers are used as means for connecting and fixing the spacers 23a and 23b for fixing the third substrate 11.
[0043]
A fixing portion 31 to which the third substrate 11 is attached is provided on a front panel 3a (see FIG. 1) of a case provided on the front side in the traveling direction of emitted light of the semiconductor light emitting element. At both ends of the fixing portion 31, flanges 31a and 31b are provided. Screw holes 32a, 32b are formed in each flange 31a, 31b. One end of the third substrate 11 is fixed by the fixing portion 31, and the other end is fixed by the spacers 23a and 23b. The spacers 23a and 23b are arranged at diagonal positions and are formed with sufficient strength to support the weight of the third substrate. As described above, since the third substrate is fixed by the two spacers arranged at diagonal positions, the number of spacers can be reduced, and the cost can be reduced.
[0044]
FIG. 8 is an exploded perspective view showing an example of fixing the second substrate 10 and the third substrate 11 shown in FIG. In FIG. 8, spacers 22a to 22d are arranged in a rectangular shape at appropriate intervals on the support plate 2 and fixed with screws or the like. When the spacers 22a to 22d are fixed to the support plate 2 by screws, a screw is formed on the inner periphery on the lower side of the spacers 22a to 22d, and a screw hole is formed in the support plate 2. Screws are inserted into the screws of the spacers 22a and 22d from the back side of the support plate 2.
[0045]
Screws 22z, 22w are formed on upper portions of the spacers 22a, 22d arranged at diagonal positions. Further, flanges 22x and 22y are formed on the upper portions of the spacers 22b and 22c arranged at different diagonal positions, and screws 22u and 22v are formed on the outer periphery on the distal end side. The flanges 22x and 22y hold the second substrate 10, and the screws 22u and 22v connect spacers 23a and 23b for fixing the third substrate 11.
[0046]
Screw holes 22p to 22s are formed on the four circumferences of the second substrate 10. The screw holes 22p and 22s are inserted into the screws 22u and 22v of the spacers 22b and 22c, and the second substrate 10 is held by the flanges 22x and 22y. At this time, the screw holes 22r and 22q of the second substrate 10 face the screws 22z and 22w formed on the inner periphery of the spacers 22a and 22d. The screws 24a and 24b are screwed into the screw holes 22z and 22w of the spacers 22a and 22d to fix the second substrate 10.
[0047]
Also, screws 23x and 23y formed on the lower inner periphery of the spacers 23a and 23b are replaced with screws 22u and 22v formed on the upper outer periphery of the spacers 22b and 22c through the screw holes 22s and 22p of the second substrate 10. Screw together. Screw holes 11u and 11v are formed at one end of the third substrate 11, and are aligned with the screw holes 32a and 32b formed in the fixing portion 31 of the case as shown in FIG. At this position, one end of the third substrate 11 is fixed with screws 11z and 11w.
[0048]
A screw hole 11s is formed at the other end of the third substrate 11, and a screw hole 11r is formed at a position diagonal to the screw hole 11s. The respective screw holes 11r and 11s of the third substrate 11 are aligned with the spacers 23b and 23a. At this position, the screws 11y and 11t are screwed into screw holes 23w and 23z formed in the inner periphery of the spacers 23b and 23a, and the other end of the third substrate 11 is fixed to the spacers 23b and 23a.
[0049]
As described above, in the support structure of the second substrate 10 and the third substrate 11 according to the present invention, four spacers having substantially the same length in a rectangular shape are fixed to the support plate on the bottom of the case. The second substrate is fixed by the two spacers at diagonal positions. The spacers for fixing the third substrate are connected to the two spacers at the remaining diagonal positions. One end of the third substrate is fixed to the two connected spacers, and the other end of the third substrate is fixed to a side plate of the case.
[0050]
For this reason, of the four spacers (first support members) fixed to the support plate, two at the diagonal positions fix the second substrate, and the remaining two diagonal spacers are at the second diagonal position. It functions as a connecting means for the fixing spacer (second support member) of the third substrate. Therefore, the four spacers have different functions, and the spacers can be effectively used for different applications. Further, a plurality of substrates can be rationally fixed to the case. Further, since one end of the third substrate is fixed by two diagonally positioned spacers, the number of required spacers is reduced, and the cost can be reduced.
[0051]
FIG. 9 is a schematic perspective view showing an example in which electronic components are mounted on the second substrate 10. In FIG. 9, electronic components 10r to 10u are mounted on the second substrate 10. Although not shown, a wiring pattern is formed on the surface of the second substrate 10. An electronic component is also mounted on the back surface of the second substrate 10, and a through hole is formed on the surface of the second substrate 10 to connect the wiring pattern on the back surface to the wiring pattern on the front surface.
[0052]
26 is a connector, 27a and 27b are cables, and 27x and 27y are terminal blocks provided on both upper and lower sides. The lower terminal block 27x is provided on the surface of the second board 10, and connects the wiring of each electronic component mounted on the second board 10 to the cables 27a and 27b. The cables 27x and 27y connected to the lower terminal block 27x are connected to the terminal block 27y at the upper part of the second substrate 10. The cable connected to the wiring of the electronic component mounted on the third board 11 is mounted on the upper terminal block 27y.
[0053]
As shown in FIG. 9, the cables 27a and 27b wired to the electronic components mounted on the second board 10 are taken out from the terminal block 27x near the center of the second board 10 and are connected to the terminal block 27y. It is connected. For this reason, since the cables 27a and 27b do not cross the electronic components near the surface of the second substrate 10, the cable arrangement does not become complicated, and the wiring processing can be performed smoothly and rationally. Further, it is possible to prevent a situation in which a cable or an operator comes in contact with the cable and damages the electronic component when the cable is wired.
[0054]
FIG. 10 is a schematic perspective view showing another embodiment of the spacer described in FIGS. In FIG. 10, a spacer 34 is a hexagonal cylindrical body in cross section, and has a screw 34a at one end and a screw hole 34b at the other end. The screw 34 a of the spacer 34 is set up on the support plate 2 with the screw 34 a facing down, and the screw 34 a is inserted into a screw hole formed in the support plate 2 and fixed. The spacers 34 are fixed at two locations on the support plate 2 at diagonal positions as described with reference to FIG. 8 (corresponding to 22a and 22d in FIG. 8), and the second substrate 10 is placed on the spacers 34. Then, the screws 24a and 24b are inserted into the screw holes 34b, and the second substrate 10 is fixed with the two spacers 34.
[0055]
Further, the spacer 34 shown in FIG. 10 is set up on the support plate 2 with the two screw holes 34b facing down at diagonal positions of the spacers 22b and 22c shown in FIG. The spacer 34 is fixed to the support plate 2 by inserting a screw from the back surface of the support plate 2 into a screw hole formed in the bottom surface of the support plate 2. Screws 34a are inserted into the screw holes 22p and 22s formed in the second substrate 10. As for the spacer 34 of FIG. 10, two screw holes 34b are also formed on the screw 34a side. This spacer is referred to as a spacer 34x.
[0056]
The screw holes 34b of the two spacers 34x are inserted into the screws 34a of the spacers 34, which are fixed to the support plate 2 from the back with screws, with the second substrate 10 interposed therebetween, and screwed. Next, the third substrate 11 is arranged on the spacer 34x as described with reference to FIG. 8, and the screws 11y and 11t are inserted into the screw holes 34b and screwed. When the spacer 34 having the shape as shown in FIG. 10 is used, the flanges 22x and 22y as shown in FIG. 8 become unnecessary, and the configuration of the spacer is simplified. The spacer may be formed in a cylindrical shape or a prism shape.
[0057]
FIG. 11 is a schematic exploded perspective view showing an example of attaching the second substrate 10 and the third substrate 11 to a case in another embodiment of the present invention. FIG. 11A shows a second substrate 10 on which mounting holes 10p to 10s are formed, and a third substrate 11 on which mounting holes 11p to 11s and mounting holes 11u and 11v are formed. I have. FIG. 11B shows an example of the support members 12 and 13.
[0058]
The support member 12 has support legs 12a and 12b erected on both sides of the case 30 (FIG. 1). The support pieces 12u and 12x are inserted into the support legs 12a in the direction of the arrow and fixed at predetermined positions (positions at which the second substrate 10 is fixed). Further, the support pieces 12v and 12y are inserted into the support leg 12b in the direction of the arrow and fixed at a predetermined position (a position at a height at which the second substrate 10 is fixed). The support member 13 includes support legs 13a and 13b and support pieces 13u, 13x, 13v, and 13y. Each support piece is similarly inserted into the support leg in the direction of the arrow, and is fixed at a predetermined position (a position at a height at which the third substrate 11 is fixed). The fixing of each support piece to each support leg is performed by applying or welding an adhesive.
[0059]
The support pieces 12x, 12y, 13x, and 13y fixed on the upper sides of the support legs 12a, 12b, 13a, and 13b are attached to positions at which the third board is fixed, and support the third board 11. . In each support piece, a screw hole is formed at a position corresponding to the mounting holes 11 p to 11 s formed in the third substrate 11. Therefore, the third substrate 11 can be fixed to the support members 12 and 13 by inserting screws through the screw holes formed in the third substrate 11 and the screw holes formed in each support piece.
[0060]
The support pieces 12u, 12v, 13u, 13v fixed below the support legs 12a, 12b, 13a, 13b support the second substrate 10. In each support piece, a screw hole is formed at a position corresponding to the mounting holes 10p to 10s formed in the second substrate 10. Therefore, the second substrate 10 can be fixed to the support members 12 and 13 by inserting screws through the screw holes formed in the second substrate 10 and the screw holes formed in each support piece. Each support leg and each support piece can be produced by metal working or molding of synthetic resin. As shown in FIG. 11, when the second substrate and the third substrate are fixed using the support legs and the support pieces, the height of the second substrate is changed by changing the mounting position of the support pieces. There is an advantage that can be set arbitrarily.
[0061]
FIG. 12 is a schematic perspective view showing another embodiment of the present invention. FIG. 12A shows an example of the support leg 13a. In this example, the support leg 13a is formed of a metal plate, and instead of the support piece, the bent piece 13x 'is bent horizontally in the direction of arrow Ra to support the third substrate 11. Further, the bent piece 13u 'is bent horizontally in the direction of arrow Rb to support the second substrate 10.
[0062]
FIG. 12B shows an example of the support leg 12b. In this example, the support leg 12b is formed of a metal plate, and instead of the support piece, the bent piece 12y 'is bent horizontally in the direction of arrow Rc to support the second substrate 10. As described above, when the supporting structure of the substrate is manufactured by bending the metal plate, the number of components is reduced, so that the cost can be reduced.
[0063]
Note that the support member 12 may have a configuration in which a slit is appropriately formed at a predetermined position of the support plate, and one end of the second substrate 10 and the third substrate is inserted into the slit and fixed. In this case, the screw holes 10r and 10s of the second substrate and the screw holes 11r and 11s of the third substrate 11 become unnecessary. Further, a supporting means for adjusting the positions of supporting claws and bolts, such as a rack mounting mechanism for a rack, can also be used. In this case, the height of the mounting position of the second substrate 10 and the third substrate 11 can be adjusted.
[0064]
FIG. 13 is a perspective view showing a different embodiment of the present invention. In the example of FIG. 13, it is assumed that an appropriate electronic component 11 d that forms a controller circuit is mounted on the third substrate 11. The third substrate 11 is arranged so as to cover the upper surface of the optical unit 5 as shown in FIG. This prevents the light emitted from the LD 14 from leaking from the upper part of the case 30.
[0065]
In the example of FIG. 13, in order to further reduce such leakage light, a cover plate 19 having a substantially gate-shaped cross section is attached to the third substrate 11. As described above, since the double light leakage prevention means including the third substrate 11 and the cover plate 19 is provided, it is possible to effectively prevent the leakage of the leakage light from the case.
[0066]
The cover plate 19 may have longitudinal slits 20a and 20b formed on both sides to release heat generated from the electronic component 11d forming the microcomputer control circuit to the outside. The slits 20a and 20b are formed above the surface on which the third substrate 11 is disposed, and the leakage light is blocked by the third substrate 11 so that the leakage light is not emitted to the outside from the slits 20a and 20b. ing.
[0067]
In the above description, a semiconductor laser element (LD) is used as a light source of the optical device. In the present invention, the light source is not limited to the semiconductor laser element, but may be an optical device that uses light emitted from a general semiconductor light emitting element. In addition, as a semiconductor light emitting element,
In _X Al _Y Ga _1-XY N (0 ≦ _X ≦ 1, 0 ≦ _Y ≦ 1, _{X + Y} ≦ 1)
Can be used.
[0068]
【The invention's effect】
As described above in detail, according to the present invention, since a plurality of substrates are stacked and arranged in multiple stages inside the case, it is possible to save the space for installing the optical device by shortening the longitudinal dimension of the case. it can. For this reason, the space on the outer periphery of the case can be effectively used for installation of other devices.
[0069]
In addition, a substrate for a semiconductor light emitting element drive circuit is arranged in the same plane as the optical axis direction of the emitted light of the semiconductor light emitting element and at a position close to the semiconductor light emitting element. Therefore, particularly when a semiconductor laser device is used as the semiconductor light emitting device, the rising and falling characteristics when a pulse voltage is applied are improved, and the operating characteristics of the semiconductor laser device can be improved.
[0070]
In addition, a substrate for a temperature adjusting circuit of the semiconductor light emitting device is disposed on a surface of the case in a direction of discharging heat generated by the semiconductor light emitting device. As described above, since the substrate for the temperature adjustment circuit is disposed on the case surface on the heat-dissipation side, the heat generated by the electronic components mounted on the substrate for the temperature adjustment circuit consumes a large amount of power during operation. Can be effectively exhausted from the case surface.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional side view of a configuration according to an embodiment of the present invention.
FIG. 2 is a schematic vertical sectional side view showing an example of an optical unit to which the present invention is applied.
FIG. 3 is an explanatory diagram of a cross section taken along line AA of FIG. 1;
FIG. 4 is a rear view as viewed from the direction of arrow B in FIG. 1;
FIG. 5 is a plan view of a second substrate.
FIG. 6 is a plan view of a third substrate.
FIG. 7 is a schematic three-dimensional view showing a state in which a second substrate is attached to a case.
FIG. 8 is an exploded perspective view showing an example of fixing a second substrate and a third substrate.
FIG. 9 is a schematic perspective view showing an example in which electronic components are mounted on a second substrate.
FIG. 10 is a perspective view showing an example of a spacer.
FIG. 11 is an exploded perspective view showing an embodiment of the present invention.
FIG. 12 is a perspective view showing another embodiment of the present invention.
FIG. 13 is a perspective view showing another embodiment of the present invention.
FIG. 14 is a circuit diagram of a semiconductor laser device (LD).
FIG. 15 is a vertical sectional side view showing an example of a conventional optical device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical apparatus, 2 ... Support plate, 3a ... Front panel, 3b ... Rear panel, 4 ... Cover, 5 ... Optical unit, 8 ... Photodiode (PD), 9 first substrate, 10 second substrate, 11 third substrate, 12, 13 support member, 14 semiconductor laser element (LD), 15. -Holder, 16a-Key switch, 16b-Interlock, 17a-17d-Opening, 19-Cover plate, 20a, 20b-Slit, 22a-22d, 23a, 23b- -Spacer, 27a, 27b-Cable, 27x, 27y-Terminal block, 28-LED display, 29-Connector, 30-Case, 31, 32-Connector

Claims (14)

In a case, a semiconductor light-emitting element, an optical unit including a plurality of optical elements in front of light emitted from the semiconductor light-emitting element, and a plurality of substrates each mounted with an electronic component for controlling operation of the semiconductor light-emitting element An optical device to be mounted, wherein the plurality of substrates are stacked and arranged in multiple stages. The optical device according to claim 1, wherein the optical unit includes at least a unit that branches outgoing light from the semiconductor light emitting element and a unit that detects the branched light. In the multi-tiered substrate, a substrate (first substrate) for a temperature adjustment circuit of the semiconductor light emitting element is disposed on a surface of a case in a direction of discharging heat generated by the semiconductor light emitting element. The optical device according to claim 1, wherein: In the substrate arranged in multiple stages, a substrate for a driving circuit of the semiconductor light emitting device (second substrate) is located in the same plane as the optical axis direction of the light emitted from the semiconductor light emitting device and at a position close to the semiconductor light emitting device. The optical device according to claim 1, wherein a substrate is disposed. The optical device according to claim 4, wherein each cable connected to the electronic component mounted on the second substrate is connected to a terminal block above the second substrate. In the multi-tiered board, a control circuit board (third board) of the semiconductor light emitting element is arranged at a position farthest from a surface of the case in a direction of discharging heat generated by the semiconductor light emitting element. The optical device according to claim 1, wherein: 7. The optical device according to claim 4, wherein the second substrate and the third substrate have electronic components mounted on both front and back surfaces. The optical device according to claim 6, wherein the third substrate is disposed so as to cover the semiconductor light emitting element and the optical unit. 9. An apparatus according to claim 6, wherein an opening is formed at one end of the third substrate at a position corresponding to the means for detecting the split light. The optical device according to any one of the preceding claims. The optical device according to claim 6, wherein an empty space for mounting an additional electronic component is provided on the third substrate. The third substrate is covered with a cover plate having a substantially gate-shaped cross-section having an open surface corresponding to at least the side on which the semiconductor light-emitting element and the optical unit are arranged, and the cover plate has a thickness greater than that of the third substrate. The optical device according to claim 6, wherein a slit is formed on a side surface on a tip side. Four first support members having substantially the same length are fixed in a rectangular shape on the surface of the case in a direction in which heat generated by the semiconductor light emitting element is exhausted, and the two first support members at diagonal positions are fixed. The second substrate is fixed by a member, and a second support member for fixing a third substrate is connected to the two first support members at the remaining diagonal positions. The optical device according to claim 6. Cables connected to electronic components mounted on each substrate are collectively mounted on the surface of the case on which one end of the first substrate, the second substrate, and the third substrate are commonly fixed. 13. The optical device according to claim 1, further comprising an opening for communicating with the outside. 14. The optical device according to claim 1, wherein the semiconductor light emitting device is a semiconductor laser device.

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