Optical devices

Abstract

To obtain a new, improved optical device that can more effectively cool an object with a cooling mechanism.SOLUTION: An optical device comprises: for example, a luminous element; a switching unit that, according to a switching instruction signal including a transmission instruction state and a blocking instruction state, switches between a transmission state for transmitting light from the luminous element and a blocking state for blocking the light from the luminous element; a light detection unit that detects the light emitted from the luminous element and passing through the switching unit; a cooling mechanism that absorbs heat from the switching unit according to the thermoelectric effect to cool the switching unit; and a control unit that controls the actuation of the cooling mechanism, and the control unit controls to actuate the cooling mechanism in conjunction with the switching instruction signal. In the optical device, the control unit may control the cooling mechanism to start actuation at a second time corresponding to a first time at which the blocking instruction state is switched to the transmission instruction state.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to an optical device.

Background Art

[0002] Conventionally, an optical device having a heating element and a temperature control device has been known (for example, Patent Document 1). In Patent Document 1, the heating element is a laser diode, and the temperature control device is a cooling mechanism having a thermoelectric element that absorbs heat from the heating element by the thermoelectric effect.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In this type of optical device, the cooling mechanism may be operated based on the detected temperature of the thermistor. However, in that case, since it takes time for the cooling mechanism to reach the peak of heat absorption from the start of operation, the peak of heat absorption is delayed with respect to the peak of heat generation, and it may be difficult to obtain the desired cooling effect.

[0005] Therefore, one of the problems of the present invention is to obtain a new and improved optical device that can more effectively cool an object by, for example, a cooling mechanism.

Means for Solving the Problems

[0006] The optical device of the present invention comprises, for example, a light-emitting element; a switching unit that switches between a transmission state in which light from the light-emitting element is transmitted and a blocking state in which light from the light-emitting element is blocked, according to a switching instruction signal that includes a transmission instruction state and a blocking instruction state; a photodetection unit that detects light from the light-emitting element that has passed through the switching unit; a cooling mechanism that cools the switching unit by absorbing heat from the switching unit through the thermoelectric effect; and a control unit that controls the operation of the cooling mechanism, wherein the control unit controls the cooling mechanism to operate in conjunction with the switching instruction signal.

[0007] In the optical device, the control unit may control the cooling mechanism to start operating at a second time point corresponding to the first time point at which the signal switches from the blockage state to the transmission state.

[0008] In the optical apparatus, the second time may be approximately the same as the first time.

[0009] In the optical apparatus, the second time step may be earlier than the first time step.

[0010] The optical device includes a temperature detection unit for detecting temperature, and the control unit may change the time difference between the first time and the second time based on the temperature detected by the temperature detection unit.

[0011] The optical device includes a temperature detection unit for detecting temperature, and the control unit may change the amount of heat absorbed by the cooling mechanism based on the temperature detected by the temperature detection unit.

[0012] In the optical device described above, the light-emitting element may be a semiconductor laser element, and the switching unit may be a semiconductor optical amplifier.

[0013] In the optical device described above, the switching unit may be manufactured integrally with the light-emitting element.

[0014] The optical device comprises a plurality of light-emitting elements as light-emitting elements, a plurality of switching units provided corresponding to each of the light-emitting elements as switching units, and a plurality of cooling mechanisms provided corresponding to each of the switching units as a cooling mechanism, wherein the light detection unit may sequentially detect light from each of the light-emitting elements via the switching units.

[0015] In the optical device described above, the switching section may be supported by support members provided in each of the cooling mechanisms and spaced apart from each other.

[0016] In the optical device described above, the switching unit may be supported by a common support member for the multiple cooling mechanisms.

[0017] In the optical device, the support member has a plurality of support portions that support each of the switching portions, and a space may be provided between adjacent support portions of the support member.

[0018] In the optical device described above, the support member has a plurality of support portions that support each of the switching portions, and a thermally conductive intervening member is provided between the support member and the switching portion, and the plurality of intervening members may be spaced apart from each other.

[0019] Furthermore, the optical device of the present invention comprises, for example, a light-emitting element, a switching unit that switches between a transmission state in which light from the light-emitting element is transmitted and a blocking state in which light from the light-emitting element is blocked, a light detection unit that detects light from the light-emitting element through the switching unit, a cooling mechanism that cools the switching unit by absorbing heat from the switching unit through the thermoelectric effect, and a control unit that controls the operation of the cooling mechanism, wherein the control unit controls the cooling mechanism to start operating approximately simultaneously with or before the switching unit switches from the blocking state to the transmission state. [Effects of the Invention]

[0020] According to the present invention, for example, a novel and improved optical device can be obtained such that an object can be cooled more effectively by a cooling mechanism.

Brief Description of the Drawings

[0021] [Figure 1] FIG. 1 is an exemplary schematic configuration diagram of an optical device according to the first embodiment. [Figure 2] FIG. 2 is an exemplary and schematic front view of an optical device according to the first embodiment. [Figure 3] FIG. 3 is an exemplary block diagram of a controller included in the optical device according to the first embodiment. [Figure 4] FIG. 4 is an exemplary timing chart showing the change over time of a switching instruction signal for a plurality of switching units of the optical device according to the first embodiment. [Figure 5] FIG. 5 is a timing chart showing an example of the change over time of a switching instruction signal, the heat generation amount of a switching unit, the drive current of a cooling mechanism, and the heat absorption amount by the cooling mechanism in one light emitting unit of the optical device according to the first embodiment. [Figure 6] FIG. 6 is a timing chart showing the change over time of a switching instruction signal, the heat generation amount of a switching unit, the drive control signal of a cooling mechanism, and the heat absorption amount by the cooling mechanism in one light emitting unit of the optical device of the reference example. [Figure 7] FIG. 7 is a timing chart showing another example of the change over time of a switching instruction signal, the heat generation amount of a switching unit, the drive control signal of a cooling mechanism, and the heat absorption amount by the cooling mechanism in one light emitting unit of the optical device according to the first embodiment. [Figure 8] FIG. 8 is an exemplary schematic configuration diagram of a light emitting module included in the optical device according to the second embodiment. [Figure 9] FIG. 9 is an exemplary and schematic front view of an optical device according to the third embodiment. [Figure 10] FIG. 10 is an exemplary and schematic front view of an optical device according to the fourth embodiment.

Embodiments for Carrying Out the Invention

[0022] The following describes several exemplary embodiments of the present invention. The configurations of the embodiments shown below, as well as the actions and results (effects) brought about by such configurations, are examples only. The present invention can also be realized by configurations other than those disclosed in the following embodiments. Furthermore, according to the present invention, it is possible to obtain at least one of the various effects (including derived effects) that can be obtained by the configuration.

[0023] The multiple embodiments shown below have similar configurations. Therefore, the configuration of each embodiment yields similar functions and effects based on the same configuration. In addition, the same reference numerals are used for these similar configurations below, and redundant explanations may be omitted.

[0024] Each diagram is schematic, and the dimensions shown may differ from those of the actual object. In each diagram, the X direction is represented by arrow X, the Y direction by arrow Y, and the Z direction by arrow Z. The X, Y, and Z directions intersect and are also orthogonal to each other.

[0025] [First Embodiment] Figure 1 is a schematic diagram of the optical device 100A(100) of the first embodiment. As shown in Figure 1, the optical device 100A(100) comprises a plurality of light-emitting modules 10-1 to 10-4(10), a light detection unit 13, and a controller 20. In this embodiment, the optical device 100 is equipped with four light-emitting modules 10, but the number of light-emitting modules 10 is not limited to four, and may be one to three or more, or five or more.

[0026] The light-emitting module 10 includes a light-emitting section 11, a switching section 12, a cooling mechanism 14, and a thermistor 15.

[0027] The light-emitting unit 11 is, for example, a chip-on-submount in which a semiconductor laser element as a light-emitting element is mounted on a submount. The laser diode is, for example, a tunable light source that can change the wavelength of the output laser light.

[0028] The light-emitting unit 11 is configured to output output light Lo, and also to output detection light Ld in the opposite direction to the direction in which the output light Lo is output (the X direction in Figure 1). The detection light Ld is input to the photodetection unit 13 via the switching unit 12. The detection light Ld is light that has the same optical properties as the output light Lo, or has a specific correspondence with the output light Lo. Therefore, by detecting the optical properties of the detection light Ld with the photodetection unit 13, the optical properties of the output light Lo, that is, the optical properties of the light output from the light-emitting element, can be detected.

[0029] The switching unit 12 can switch between a state in which it transmits light from the light-emitting unit 11 and a state in which it blocks light from the light-emitting unit 11. The switching unit 12 is, for example, a semiconductor optical amplifier. In this case, when a forward bias voltage is applied as the switching instruction signal Ss, the switching unit 12 amplifies and transmits the light from the light-emitting unit 11 and outputs it to the photodetector 13. On the other hand, when a reverse bias voltage is applied, the switching unit 12 absorbs and blocks the light from the light-emitting unit 11, so no detected light Ld is input to the photodetector 13.

[0030] The switching unit 12 generates heat when light from the light-emitting unit 11 is transmitted through it. Therefore, in this embodiment, a cooling mechanism 14 is provided to suppress the temperature rise caused by the heat generated by the switching unit 12. The switching unit 12 may also be referred to as a heat-generating element.

[0031] The cooling mechanism 14 is, for example, a thermoelectric cooler (TEC) having a thermoelectric element (Peltier element). The cooling mechanism 14 cools the switching section 12 by absorbing heat from it through the thermoelectric effect generated by applying an electric current to the thermoelectric element.

[0032] Figure 2 is a front view of the optical device 100A. As shown in Figure 2, the cooling mechanism 14 is provided corresponding to each of the light-emitting modules 10, i.e., each of the switching units 12. The cooling mechanism 14 has a plurality of thermoelectric elements 14a arranged in series or parallel, a bottom plate 14b, and a top plate 14c. The plurality of thermoelectric elements 14a are provided sandwiched between the bottom plate 14b and the top plate 14c. The plurality of thermoelectric elements 14a are electrically connected to each cooling mechanism 14 via wiring (not shown) provided on the bottom plate 14b and the top plate 14c, and are configured so that cooling operation can be performed for each cooling mechanism 14 by energizing it. The light-emitting unit 11 (not shown in Figure 2) and the switching unit 12 are placed on and supported on the top plate 14c. The top plate 14c is an example of a support member.

[0033] As shown in Figure 2, in this embodiment, the bottom plate 14b is common to multiple cooling mechanisms 14. This configuration has the advantage of reducing the number of parts, thereby lowering manufacturing effort and cost.

[0034] On the other hand, the top plates 14c are configured to be spaced apart from each other. This prevents heat from being transferred between the multiple switching sections 12 via the top plates 14c, which would impair the cooling effect of the cooling mechanism 14.

[0035] As shown in Figure 1, the photodetector 13 can detect the characteristics of the detection light Ld input from multiple light-emitting units 11 via the switching unit 12. The photodetector 13 is, for example, a wavelength rocker and can detect the wavelength of the detection light Ld. If multiple photodetector units 13 are provided, for example, one for each light-emitting unit 11, then if there is a variation in detection among these multiple photodetector units 13, it may adversely affect the control of the light-emitting element (for example, wavelength tunable control) based on the detection results of the photodetector 13. In this embodiment, however, since the photodetector 13 is common to multiple light-emitting units 11, it is possible to suppress the effect of the detection variation of the photodetector 13 on the control of the light-emitting element.

[0036] The controller 20 controls the operation of the cooling mechanism 14. Figure 3 is a block diagram of the controller 20. As shown in Figure 3, the controller 20 is configured as a computer having an arithmetic unit 21, a main memory unit 22, and an auxiliary storage device 23. The arithmetic unit 21 is a processor (circuit), such as a CPU; the main memory unit 22 is, for example, RAM or ROM; and the auxiliary storage device 23 is a non-volatile storage unit, such as an SSD or HDD. The arithmetic unit 21 operates according to a program stored and installed in the main memory unit 22 or the auxiliary storage device 23, and functions as an instruction signal acquisition unit 21a, a cooling mechanism control unit 21b, a temperature detection unit 21c, etc. The controller 20 is an example of a control unit.

[0037] The programs may be provided as installable or executable files, recorded on a computer-readable storage medium. The storage medium may also be referred to as a program product. The programs and information such as values, tables, and maps used in the processor's arithmetic processing may be pre-stored in the main memory 22 or auxiliary storage device 23, or they may be stored in the memory of a computer connected to a communication network and downloaded to the auxiliary storage device 23 via the communication network. The main memory 22 and auxiliary storage device 23 also store data written by the processor. Furthermore, the arithmetic processing by the controller 20 may be executed by hardware at least partially. In this case, the controller 20 may include, for example, an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit).

[0038] The instruction signal acquisition unit 21a acquires the switching instruction signal Ss input to the switching unit 12. Figure 4 is a timing chart showing the change over time (time: t) of the switching instruction signal Ss input to each light-emitting module 10 (10-1 to 10-4). In the switching instruction signal, an H level state is a transmission instruction state, and an L level state is a blockage instruction state. When the switching instruction signal is at an H level, i.e., a transmission instruction state, the switching unit 12 enters a transmission state, and when the switching instruction signal is at an L level, i.e., a blockage instruction state, the switching unit 12 enters a blockage state. As is clear from Figure 4, the optical device 100 is configured such that the switching instruction signals Ss input to the multiple switching units 12 sequentially become H level, and the multiple switching units 12 sequentially enter a transmission state, allowing the detection light Ld to pass through to the photodetection unit 13. The photodetection unit 13 sequentially detects the detection light Ld output from the light-emitting unit 11 and passed through the switching units 12.

[0039] Furthermore, as shown in Figure 4, in this embodiment, the switching instruction signal Ss is a signal output by a control unit (not shown) that controls the switching unit 12, and is not a signal that is generated suddenly in response to changes in phenomena, etc., but rather a signal whose timing for switching between the H level and the L level is known in advance.

[0040] The cooling mechanism control unit 21b controls a switch element (not shown) and the like so that a drive control signal Dt (see Figure 1) is input from the power supply (not shown) to each cooling mechanism 14 in conjunction with the switching instruction signal Ss, thereby operating the cooling mechanism 14. In other words, the cooling mechanism control unit 21b controls the operation of the cooling mechanism 14 in conjunction with the switching instruction signal Ss.

[0041] Figure 5 is a timing chart showing an example of the time-dependent changes (time: t) of the switching instruction signal Ss, the amount of heat generated by the switching unit 12 Eh, the drive control signal Dt output by the controller 20 to the cooling mechanism 14, and the amount of heat absorbed by the cooling mechanism 14 Ea in this embodiment. As shown in Figure 5, at time tss, the switching instruction signal Ss switches from L level to H level, and accordingly, the switching unit 12 changes from a blocked state to a permeable state, and the switching unit 12 begins to generate heat. As a result, the amount of heat generated by the switching unit 12 Eh begins to increase from a time slightly after time tss, peaks at time tps, and then decreases.

[0042] Furthermore, the amount of heat absorbed by the cooling mechanism 14, Ea, begins to increase slightly after the time tsd when the drive control signal Dt is first input to the cooling mechanism 14, peaks at time tpa, and then decreases. In Figure 5, the amount of heat generated, Eh, increases as you move upwards, while the amount of heat absorbed, Ea, increases as you move downwards.

[0043] As described above, in this embodiment, the cooling mechanism control unit 21b controls the cooling mechanism 14 to operate in conjunction with the switching instruction signal Ss. Specifically, in the example shown in Figure 5, the time tsd at which the cooling mechanism 14 starts operating is set to be approximately the same as the time tss at which the switching instruction signal Ss switches from L level to H level. This makes it possible to bring the time tpa at which the heat absorption amount Ea by the cooling mechanism 14 peaks closer to the time tph at which the heat generation amount Eh by the switching unit 12 peaks, and to more effectively absorb and suppress the heat generated by the switching unit 12 by the cooling mechanism 14. Time tss is an example of a first time, and time tsd is an example of a second time.

[0044] Figure 6 is a timing chart showing the time-dependent changes (time: t) of the switching instruction signal Ss, heat generation amount Eh, drive control signal Dt, and heat absorption amount Ea when, for example, time tsd is not approximately the same as time tss, and the cooling mechanism 14 is activated when, for example, the detected temperature of the thermistor 15 (see Figure 1), which is provided in correspondence with the switching unit 12, exceeds a threshold. As is clear from Figure 6, in this case, there is a time lag between the start of heat generation from the switching unit 12 and the detection temperature of the thermistor 15 exceeding the threshold. Therefore, a time difference TD occurs between time tpa, when the heat absorption amount Ea by the cooling mechanism 14 peaks, and time tph, when the heat generation amount Eh by the switching unit 12 peaks. As a result, the cooling mechanism 14 cannot absorb the heat generated by the switching unit 12 more effectively. With such passive control, it is difficult to cool the switching unit 12 more effectively with the cooling mechanism 14. In this embodiment, the cooling mechanism 14 can be used to more effectively cool the switching unit 12 by actively controlling the cooling mechanism 14 in conjunction with a known switching instruction signal Ss.

[0045] Figure 7 is a timing chart showing an example of the time-dependent changes (time: t) of the switching instruction signal Ss, heat generation amount Eh, drive control signal Dt, and heat absorption amount Ea in this embodiment. As shown in Figure 7, in this embodiment, the time tsd at which the cooling mechanism 14 starts operating is set before the time tss at which the switching instruction signal Ss switches from L level to H level. For example, if the time from the time tsd at which the cooling mechanism 14 starts operating to the time at which the heat absorption amount Ea peaks is longer, as in this example, by setting the start time tsd at which the operation starts before the time tss at which the switching instruction signal Ss switches from L level to H level, the time tpa at which the heat absorption amount Ea by the cooling mechanism 14 peaks and the time tph at which the heat generation amount Eh by the switching unit 12 peaks can be brought closer together. In this case, the controller 20 controls the switching unit 12 along with the cooling mechanism 14, or the instruction signal acquisition unit 21a may receive information in advance from another controller (not shown) that outputs a switching instruction signal Ss, indicating the time at which the switching instruction signal Ss will be output, or it may receive a signal from the other controller instructing the start of operation of the cooling mechanism 14.

[0046] Furthermore, in this embodiment, as shown in Figure 1, each light-emitting module 10 has a thermistor 15 for detecting the temperature of the switching unit 12, and as shown in Figure 3, the calculation unit 21 of the controller 20 has a temperature detection unit 21c. The temperature detection unit 21c can detect the temperature of the switching unit 12 based on the value detected by the thermistor 15.

[0047] The cooling mechanism control unit 21b can change the time difference δt (see Figure 7) between the time tss, when the switching instruction signal Ss switches from L level to H level, and the time tsd, when the cooling mechanism 14 starts operating, according to the temperature of the switching unit 12 detected by the temperature detection unit 21c (hereinafter simply referred to as the detected temperature). For example, if the detected temperature is high, time tsd can be set before time tss, and the higher the detected temperature, the larger the time difference δt (absolute value) can be set. Conversely, if the detected temperature is low, time tsd can be set after time tss, and the lower the detected temperature, the larger the time difference δt (absolute value) can be set.

[0048] Furthermore, the cooling mechanism control unit 21b can change the peak current value I of the drive control signal Dt according to the detected temperature, thereby changing the peak value Q of the heat absorbed amount Ea. For example, when the detected temperature is high, the peak value Q can be set to be higher by making the peak current value I larger compared to when the detected temperature is low, and the higher the detected temperature, the larger the peak current value I and thus the peak value Q can be set to. Conversely, when the detected temperature is low, the peak value Q can be set to be lower by making the peak current value I smaller compared to when the detected temperature is high, and the lower the detected temperature, the smaller the peak current value I and thus the peak value Q can be set to.

[0049] The cooling mechanism control unit 21b can determine and change the time tsd, time difference δt, peak current value I, etc. (hereinafter referred to as control values) corresponding to the detected temperature as described above, by referring to mathematical formulas, functions, tables, maps, etc. that show the correlation between the detected temperature and the control values, which are stored in the main memory unit 22 or the auxiliary storage device 23. These mathematical formulas, functions, tables, maps, etc. that show the correlation are acquired in advance and stored, for example, in the main memory unit 22 or the auxiliary storage device 23. The correlation may also be described in a program.

[0050] As described above, in this embodiment, the controller 20 controls the operation of the cooling mechanism 14 in conjunction with the switching instruction signal Ss. Therefore, according to this embodiment, the switching unit 12 can be cooled more efficiently and effectively.

[0051] Furthermore, in this embodiment, the controller 20 can control the cooling mechanism 14 to start operating approximately simultaneously with or before the start of operation of the switching unit 12. Therefore, according to this embodiment, the switching unit 12 can be cooled more efficiently and effectively in some cases.

[0052] [Second Embodiment] Figure 8 is a schematic diagram of the light-emitting module 10B(10) of the second embodiment. In this embodiment, the configuration of the light-emitting module 10B differs from that of the first embodiment. The light-emitting module 10B has a single semiconductor element 16a, in which the light-emitting section 11 and the switching section 12 are integrated. The semiconductor element 16a is mounted on a submount 16b, and the semiconductor element 16a and the submount 16b constitute a chip-on-submount 16. The light-emitting module 10B can be incorporated into the optical device 100 of the first embodiment. Even in an optical device 100 equipped with such a light-emitting module 10B, the controller 20 controls the cooling mechanism 14 in the same way as in the first embodiment, thereby obtaining the same operation and effects as in the first embodiment. Furthermore, when the light-emitting unit 11 and the switching unit 12 are integrated, as in this embodiment, compared to when the light-emitting unit 11 and the switching unit 12 are provided separately, advantages can be obtained, such as higher coupling efficiency between the light-emitting unit 11 and the switching unit 12, and reduced manufacturing effort and cost due to a reduction in the number of parts.

[0053] [Third Embodiment] Figure 9 is a front view of the optical device 100C(100) of the third embodiment. As can be seen by comparing Figure 9 with Figure 2, the structure of the cooling mechanism 14 in this embodiment differs from that of the first embodiment. In this embodiment, the top plate 14cC is common to multiple cooling mechanisms 14. However, each top plate 14cC has multiple support parts 14c1 that support the switching part 12, and a space S is provided between adjacent support parts 14c1. The space S can be provided in the top plate 14cC as, for example, a groove, a slit, a through hole, etc. The cross-sectional shape and plan view shape of the space S can be any shape.

[0054] In this embodiment as well, the controller 20 controls the cooling mechanism 14 in the same manner as in the first embodiment, thereby achieving the same operation and effects as in the first embodiment. Furthermore, in this embodiment, the top plate 14cC is common to multiple cooling mechanisms 14. This configuration reduces the number of parts, which has the advantage of reducing manufacturing effort and cost. In addition, according to this embodiment, by providing a space S, heat is less likely to be transferred between adjacent support parts 14c1, thus preventing heat from being transferred between multiple switching parts 12 via the top plate 14cC and impairing the cooling effect of the cooling mechanism 14.

[0055] [Fourth Embodiment] Figure 10 is a front view of the optical device 100D(100) of the fourth embodiment. As can be seen by comparing Figure 10 with Figure 2, the support structure of the switching unit 12 in this embodiment differs from that of the first embodiment. In this embodiment, the top plate 14cD is common to multiple cooling mechanisms 14. However, an insulating and thermally conductive intervening member 17 is provided between the top plate 14cD and the switching unit 12, and the multiple intervening members 17 are arranged spaced apart from each other.

[0056] In this embodiment as well, the controller 20 controls the cooling mechanism 14 in the same manner as in the first embodiment, thereby achieving the same operation and effects as in the first embodiment. Furthermore, in this embodiment, the top plate 14cD is common to multiple cooling mechanisms 14. This configuration reduces the number of parts, which has the advantage of reducing manufacturing effort and cost. In addition, according to this embodiment, by providing an intervening member 17 between the top plate 14cD and the switching unit 12, heat is less likely to be transferred between adjacent intervening members 17. Therefore, heat transfer between multiple switching units 12 via the top plate 14cD and intervening members 17, which impairs the cooling effect of the cooling mechanism 14, can be suppressed.

[0057] Although embodiments of the present invention have been illustrated above, these embodiments are merely examples and are not intended to limit the scope of the invention. The above embodiments can be implemented in various other forms, and various omissions, substitutions, combinations, and modifications can be made without departing from the spirit of the invention. Furthermore, each configuration, shape, and other specifications (structure, type, orientation, model, size, length, width, thickness, height, number, arrangement, position, material, etc.) can be modified as appropriate. [Explanation of symbols]

[0058] 10, 10-1 to 10-4, 10B… Light-emitting modules 11…Light-emitting part (luminescent element) 12…Switching section 13…Light detection unit 14…Cooling mechanism 14a... Thermoelectric element 14b…Bottom plate 14c, 14cC, 14cD… Tabletop 14c1…Support part 15…Thermistor 16…Chip-on-submount 16a... Semiconductor element 16b... Submount 17…Intervening member 20… Controller 21...Arithmetic section 21a...Instruction signal acquisition section 21b...Cooling mechanism control unit 21c...Temperature detection unit 22...Main memory section 23…Auxiliary storage device 100,100A,100C,100D…Optical device Dt... Drive control signal Ea…Amount of heat absorption Eh... Heat generation I...Peak current value Ld...Detection light Lo... Output light Q... Peak value S…Space Ss... Switching instruction signal t…Time tpa...time tph…moment TPS... Moments TSD…time (second time) tss… moment (first moment) X…direction Y...direction Z…direction

Claims

1. Multiple light-emitting elements, Each of the aforementioned light-emitting elements is provided with a plurality of switching units that switch between a transmission state, in which light from the light-emitting element is transmitted, and a blocking state, in accordance with a switching instruction signal that includes a transmission instruction state and a blocking instruction state. A light detection unit that detects light from the light-emitting element via the switching unit, It comprises a single base plate, a plurality of top plates arranged parallel to the base plate at equal intervals and spaced apart from each other, and a plurality of thermoelectric elements interposed between the base plate and each of the top plates, and a plurality of cooling mechanisms that cool the switching section provided on each top plate by absorbing heat through the thermoelectric effect, A control unit that controls the operation of each of the cooling mechanisms, Equipped with, The control unit controls the cooling mechanism to operate in conjunction with the switching instruction signal. The light detection unit is an optical device that sequentially detects light from each of the light-emitting elements via the switching unit.

2. The optical device according to claim 1, wherein each of the plurality of top plates is provided with a light-emitting unit including the light-emitting unit corresponding to each of the switching units.

3. Multiple light-emitting elements, Each of the aforementioned light-emitting elements is provided with a plurality of switching units that switch between a transmission state, in which light from the light-emitting element is transmitted, and a blocking state, in accordance with a switching instruction signal that includes a transmission instruction state and a blocking instruction state. A light detection unit that detects light from the light-emitting element via the switching unit, It has one base plate, one top plate parallel to the base plate, and a plurality of thermoelectric elements interposed between the base plate and the top plate, and a plurality of cooling mechanisms provided for each switching section that cool the switching section by absorbing heat from the switching section through the thermoelectric effect, A control unit that controls the operation of each of the cooling mechanisms, Equipped with, The control unit controls the cooling mechanism to operate in conjunction with the switching instruction signal. The light detection unit sequentially detects light from each of the light-emitting elements via the switching unit, An optical device having a space provided on the top plate between two adjacent cooling mechanisms.

4. The optical apparatus according to claim 1 or 3, wherein the control unit controls the cooling mechanism to start operating at a second time corresponding to the first time when the state switches from the shut-off state to the transmission state.

5. The optical apparatus according to claim 4, wherein the second time is substantially the same as the first time.

6. The optical apparatus according to claim 4, wherein the second time is earlier than the first time.

7. It is equipped with a temperature detection unit that detects temperature, The optical apparatus according to any one of claims 4 to 6, wherein the control unit changes the time difference between the first time and the second time based on the temperature detected by the temperature detection unit.

8. It is equipped with a temperature detection unit that detects temperature, The optical apparatus according to any one of claims 1 to 7, wherein the control unit changes the amount of heat absorbed by the cooling mechanism based on the temperature detected by the temperature detection unit.

9. The light-emitting element is a semiconductor laser element, The optical apparatus according to any one of claims 1 to 8, wherein the switching unit is a semiconductor optical amplifier.

10. The optical device according to claim 9, wherein the switching unit is integrally manufactured with the light-emitting element.

11. The optical apparatus according to any one of claims 1 to 10, wherein the control unit controls the cooling mechanism so that it starts operating approximately simultaneously with or before the switching unit switches from the blocking state to the transmitting state.

Images