Lighting device and control method

Abstract

To provide a lighting device and a control method with which it is possible to suppress a rise of temperature in the vicinity of a light source.SOLUTION: The lighting device comprises: a first object part that includes a light source; a second object part that is different from the light source; light emission control means that controls the light emission operation of the light source; calculation means that calculates a first control temperature that is the relative temperature of the first object part and a second control temperature that is the relative temperature of the second object part, on the basis of the heat generated by the light emission operation of the light source; and control means that controls the light emission operation on the basis of at least one of the first and second control temperatures. The calculation means calculates the first control temperature on the basis of the first level of impact of heat due to the light emission operation, and calculates the second control temperature on the basis of the second level of impact of heat due to the light emission operation that is different from the first level of impact.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a lighting device and a control method thereof, and more particularly to a lighting device capable of suppressing a temperature rise due to light emission. [Background technology]

[0002] Conventionally, some lighting devices appropriately control the temperature rise of an optical panel disposed in front of the lighting device so that the optical panel remains within a safe temperature range when the light-emitting unit emits light continuously.

[0003] Patent Document 1 discloses an illumination device that controls the operating output of a cooling unit that cools an optical panel based on a control temperature that is a relative temperature of the optical panel.

[0004] Furthermore, Patent Document 2 discloses a flashlight device that performs processing to mitigate the temperature rise of heat-generating components when the total amount of light emitted reaches a predetermined value within a predetermined time, based on the duration and amount of light emitted during the flashlight emission. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-60558 [Patent Document 2] JP 2006-58490 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the above-mentioned Patent Documents 1 and 2 do not take into consideration the temperature rise near the light source due to differences in light emission operation. In particular, when shooting using an illumination device, in light emission operations such as multiple emission in which the light source repeatedly emits light in a short period of time and flat emission in which the light source continues to emit light for a longer period of time than flash emission, there is a risk that the light source will stop emitting light due to a rise in temperature of the light source.

[0007] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide a lighting device capable of suppressing a rise in temperature near the light source and a control method thereof. [Means for solving the problem]

[0008] In order to achieve the above-mentioned object, the lighting device of the present invention comprises a first target part including a light source, a second target part different from the light source, a light-emitting control means for controlling the light-emitting operation of the light source, a calculation means for calculating a first control temperature which is a relative temperature of the first target part and a second control temperature which is a relative temperature of the second target part based on heat generated by the light-emitting operation of the light source, and a control means for controlling the light-emitting operation based on at least one of the first and second control temperatures, wherein the calculation means calculates the first control temperature based on a first degree of influence of heat due to the light-emitting operation, and calculates the second control temperature based on a second degree of influence of heat due to the light-emitting operation which is different from the first degree of influence. Effect of the Invention

[0009] According to the present invention, it is possible to suppress a rise in temperature near the light source. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a schematic configuration of a lighting device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view of the lighting device. [Diagram 3] 4 is a flowchart of a light emission process of the lighting device according to the first embodiment of the present invention. [Figure 4] 4 is a flowchart of a state confirmation process in step S302 of FIG. 3 according to the first embodiment of the present invention. [Diagram 5] 4 is a flowchart of a panel continuous light emission control process in step S311 of FIG. 3 according to the first embodiment of the present invention. [Figure 6]4 is a flowchart of a discharge tube continuous light emission control process in step S312 of FIG. 3 according to the first embodiment of the present invention. [Figure 7] 6 is a flowchart of a light emission energy NL calculation process in step S503 of FIG. 5 according to the first embodiment of the present invention. [Figure 8] 3 is a diagram showing a heat transfer model of a light-emitting section in the lighting device according to the first embodiment of the present invention. FIG. [Figure 9] 7 is a flowchart of a panel control stage determination process in step S508 of FIG. 5. [Figure 10] 6 is a flowchart of the zoom position change process in step S513 in FIG. 5. [Figure 11] 6 is a flowchart of a cooling unit drive control process that is executed every time a control temperature Tf is calculated in step S507 in FIG. 5. [Figure 12] 1 is a graph showing actual measured temperatures of an optical panel and estimated panel temperatures. [Figure 13] FIG. 2 is a diagram showing a heat transfer model of a discharge tube in the lighting device according to the first embodiment of the present invention. [Figure 14] 7 is a flowchart of a discharge tube control stage determination process in step S608 of FIG. 6 according to the first embodiment of the present invention. [Figure 15] 1 is a graph showing actual measured temperature values ​​of a discharge tube and its estimated temperature. [Figure 16] 1 is a graph showing a time axis from the start to the end of light emission of the discharge tube 104. [Figure 17] 7 is a flowchart of a discharge tube control stage determination process in step S608 of FIG. 6 according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0012] (First embodiment) Fig. 1 is a block diagram showing a schematic configuration of a lighting device 100 as a lighting device according to a first embodiment of the present invention. Fig. 2 is a diagram showing a schematic cross section of the lighting device 100. Note that the same components are denoted by the same reference numerals in Fig. 1 and Fig. 2.

[0013] First, the configuration of the lighting device 100 will be described. As shown in Fig. 2, the lighting device 100 is composed of a main body 100a that is detachably attached to a camera body (not shown), and a light emitting unit 100b that is held rotatably in the up-down and left-right directions relative to the main body 100a. In this embodiment, the rotation direction of the light emitting unit 100b is defined as the upper side of the main body 100a that is connected to the light emitting unit 100b.

[0014] A microcomputer FPU (hereinafter, microcomputer) 101 controls each part of the lighting device 100. The microcomputer 101 has a circuit configuration of a one-chip IC with a built-in microcomputer including, for example, a CPU, a ROM, a RAM, an input / output control circuit (I / O control circuit), a multiplexer, a timer circuit, an EEPROM, an A / D, and a D / A converter.

[0015] The battery 200 functions as a power source (VBAT) for the lighting device 100. As shown in Fig. 1, the boost circuit block 102 is composed of a boost unit 102a, resistors 102b and 102c used for voltage detection, and a main capacitor 102d. The boost circuit block 102 boosts the voltage of the battery 200 to several hundred volts by the boost unit 102a, and charges the main capacitor 102d with electrical energy for light emission. The charging voltage of the main capacitor 102d is divided by the resistors 102b and 102c, and the divided voltage is input to an A / D conversion terminal MCV_AD of the microcomputer 101.

[0016] The trigger circuit 103 applies a pulse voltage to the discharge tube 104 to excite the discharge tube 104, which will be described later. The light emission control circuit 105 controls the start and stop of light emission of the discharge tube 104. When the discharge tube 104 (light source) receives a pulse voltage of several KV applied from the trigger circuit 103, it is excited and emits light using the electric energy charged in the main capacitor 102d.

[0017] The photodiode 106 is a sensor that receives light emitted from the discharge tube 104, and receives the light emitted from the discharge tube 104 directly or via a glass fiber or the like. The integration circuit 107 integrates the light-receiving current of the photodiode 106, and the output is input to the inverting input terminal of the comparator 108 and the A / D converter terminal INT_AD of the microcomputer 101. The non-inverting input terminal of the comparator 108 is connected to the D / A converter terminal INT_DAC in the microcomputer 101, and the output of the comparator 108 is connected to the input terminal of an AND gate 109. The other input of the AND gate 109 is connected to the light emission control terminal FL_START of the microcomputer 101, and the output of the AND gate 109 is input to the light emission control circuit 105.

[0018] The reflector 110 reflects the light emitted from the discharge tube 104 and guides it in a predetermined direction. The optical panel 111 is an optical member disposed in front of the discharge tube 104 and is included in a zoom optical system (not shown), and is held so that the relative position (zoom position) with respect to a reflector unit 112 including the discharge tube 104 and the reflector 110 can be changed. In this way, by changing the relative position between the reflector unit 112 and the optical panel 111, the irradiation angle of the lighting device 100 can be changed, and the guide number can be changed. The light emitting unit 100b is mainly composed of the discharge tube 104, the reflector 110, and the optical panel 111, and the irradiation direction thereof can be changed by rotating it from the main body unit 100a.

[0019] The input unit 113 includes a power switch, a mode setting switch for setting an operation mode of the lighting device 100 including a drive setting of a cooling unit 117 described below in response to a user operation, and setting buttons for setting various other parameters in response to a user operation. The microcomputer 101 executes various processes in response to an input to the input unit 113. The display unit 114 has a liquid crystal device and a light emitting element, and displays each state of the lighting device 100.

[0020] The zoom drive circuit 115 is composed of a zoom detection unit 115a that detects information about the relative positions of the reflector unit 112 and the optical panel 111 using an encoder or the like, and a zoom drive unit 115b that includes a motor for moving the reflector unit 112. The amount of movement of the reflector unit 112 by the zoom drive unit 115b is calculated by the microcomputer 101 based on focal length information of the photographing lens obtained via the camera body.

[0021] Terminals 116 include a terminal SCLK_S for synchronizing communications between the camera body and lighting device 100, a terminal MOSI_S for transmitting data from the camera body to the lighting device 100, and a terminal MISO_S for receiving data transmitted from the lighting device 100. Terminals 116 also include a GND terminal connecting both the camera body and the lighting device 100. An engagement portion (not shown) for engaging with the camera body is provided near terminal 116.

[0022] The cooling unit 117 is a module having a fan for cooling the optical panel 111, and is connected to the terminals FAN_PWM and FAN_FG of the microcomputer 101. The cooling unit 117 can change the rotation speed of the fan by PWM control from the microcomputer 101, thereby changing the output air volume. Also, by feeding back rotation speed information to the microcomputer 101, it is possible to maintain the rotation speed as instructed.

[0023] Next, a light emission process of the lighting device 100 according to this embodiment will be described with reference to Fig. 3. This process is executed by a CPU included in the microcomputer 101 reading out a program stored in a ROM also included in the microcomputer 101.

[0024] When a power switch included in the input unit 113 is turned on and the microcomputer 101 of the lighting device 100 becomes operable, the microcomputer 101 starts a light emission process shown in the flowchart of FIG.

[0025] In step S301, the microcomputer 101 initializes its own memory and ports. It also reads the state of the switches included in the input unit 113 and preset input information, sets various light emission modes such as how to determine the amount of light emission and the timing of light emission, and then proceeds to step S302.

[0026] In step S302, the microcomputer 101 stores the result of the state confirmation process in the RAM of the microcomputer 101, and proceeds to step S303. Details of the state confirmation process will be described later with reference to the flowchart of FIG.

[0027] In step S303, the microcomputer 101 causes the boost circuit block 102 to start its operation and charge the main capacitor 102d. After starting charging the main capacitor 102d, the process proceeds to step S304.

[0028] In step S304, microcomputer 101 acquires focal length information of the photographing lens from the camera body via terminal 116, stores the acquired focal length information in RAM included in microcomputer 101, and then proceeds to step S305. Note that if focal length information has already been stored in RAM, the focal length information in the RAM is updated to the newly acquired focal length information in step S304.

[0029] In step S305, the microcomputer 101 causes the zoom driving circuit 115 to move the reflector unit 112 so that the light distribution angle of the light emitted from the lighting device falls within a range corresponding to the focal length information acquired in step S304, and then proceeds to step S306. Note that if there is no need to move the reflector unit 112, the microcomputer 101 proceeds directly to step S306.

[0030] In step S306, the microcomputer 101 displays on the display unit 114 an image related to the light emission mode set by the input unit 113 in step S301, an image related to the focal length information acquired in step S304, etc. Also, if an error state is detected in any of the hardware related to the continuous light emission process in the status confirmation process of step S302, a warning display according to the error content is performed. Then, the process proceeds to step S307.

[0031] In step S307, the microcomputer 101 checks whether charging of the main capacitor 102d is complete based on the voltage input to the A / D conversion terminal MCV_AD. If charging is complete, the microcomputer 101 transmits a charging completion signal to a camera microcomputer (not shown) in the camera body via the terminal 116 and proceeds to step S308, and if charging is not complete, returns to step S302.

[0032] In step S308, the microcomputer 101 determines whether or not a light emission start signal has been received from the camera microcomputer as a light emission instruction, and if so, proceeds to step S309, and if not, returns to step S302.

[0033] In step S309, the microcomputer 101 instructs the light emission control circuit 105 to emit light in response to the received light emission start signal, and the light emission control circuit 105 causes the discharge tube 104 to emit light in accordance with the light emission instruction. After the light emission ends, information related to the light emission, such as voltage information of the main capacitor 102d, is stored in a RAM included in the microcomputer 101, and the process proceeds to step S310. Note that, for a series of light emissions such as pre-flash and main flash for dimming, the process proceeds to step S310 after the series of light emissions ends in step S309.

[0034] In step S310, the microcomputer 101 determines whether the emission in step S309 is the first emission, that is, whether it is the first emission since the start of the emission process in Fig. 3. If it is the first emission, the process proceeds to step S311, and if it is the second or subsequent emission, the process returns to step S302. Note that when a series of emissions such as pre-emission for dimming and main emission are performed, if no emission is performed before the series of emissions, it is considered to be the first emission.

[0035] In step S311, the microcomputer 101 starts a continuous light emission control process for panel that controls light emission and charging so that the temperature of the optical panel 111 does not rise too much even if heat due to light emission is continuously applied to the optical panel 111 during continuous light emission, and then proceeds to step S312. Details of the continuous light emission control process for panel will be described later using the flowchart in FIG.

[0036] In step S312, the microcomputer 101 starts a continuous light emission control process for the discharge tube, which controls light emission and charging so that the temperature of the discharge tube 104 does not rise too much even if heat caused by light emission continues to be applied to the discharge tube 104 during continuous light emission, and returns to step S302. Details of the continuous light emission control process for the discharge tube will be described later using the flowchart in FIG.

[0037] In the case where the control temperatures Tf, Tfx and other calculation results described later are not in the initial state, the continuous light emission control processes in steps S311 and S312 are repeatedly calculated, and are terminated when the calculation results return to the initial state. That is, in order to protect the optical panel 111 and the discharge tube 104 from the influence of heat due to the light emission in step S308, the calculation of each assumed temperature or a counter that serves as a substitute for the temperature is started after the first light emission is completed. Then, the continuous light emission control processes in Figs. 5 and 6 are continued in parallel with the light emission process in Fig. 3 until the calculation results of each counter become the same as the initial state due to the passage of time caused by heat dissipation or a reset process. In this embodiment, the processes in Figs. 5 and 6 are continuous light emission control processes, but similar processes may be performed for single light emission. After starting each continuous light emission control process in this way, the process returns to step S302.

[0038] Next, the status confirmation process (step S302) in the lighting device 100 will be described with reference to the flowchart of FIG. 4. This process is executed to confirm the status of hardware (target hardware) related to the panel continuous light emission control process. The target hardware refers to components that affect the optical system and heat source. Specifically, it includes the cooling unit 117 that cools the optical panel 111, and optical accessories (not shown) such as a color filter and a bounce adapter that are attached in front of the optical panel 111. In addition, the target hardware may also include an external power source (not shown) that speeds up the charging of the main capacitor 102d, a modeling LED (not shown) that makes it easier to grasp the optical axis of the light irradiated from the optical panel 111, and the like.

[0039] In step S401, the microcomputer 101 acquires status information of the target hardware. The status information includes information indicating whether each piece of target hardware is mounted and connected to the lighting device 100, and an operation enable / disable setting by the input unit 113. The status information, together with error information described below, is updated every time a change occurs in the status of the target hardware. The acquired status information of the target hardware related to the panel continuous light emission control process is stored in the RAM included in the microcomputer 101, and the process proceeds to step S402.

[0040] In step S402, the microcomputer 101 detects whether the target hardware itself is in an error state based on the state information of the target hardware acquired in step S401. For example, even if the cooling unit 117 is connected to the lighting device 100 and the cooling unit 117 is operable in the light emission mode setting performed in step S301, the cooling unit 117 may be inoperable due to a malfunction or the like. In this case, it is detected that the cooling unit 117 itself, which is the target hardware, is in an error state. If the result of the detection is that the target hardware itself is in an error state, information indicating that fact is acquired as error information in the RAM included in the microcomputer 101, and the process proceeds to step S403.

[0041] In step S403, the microcomputer 101 stores the information acquired in steps S401 and S402 in the RAM included in the microcomputer 101, and ends this process.

[0042] Next, the panel continuous light emission control process (step S311) in the lighting device 100 will be described with reference to the flowchart in Fig. 5. This process is for suppressing a temperature rise in the optical panel 111 caused by the influence of heat generated by the light emission of the discharge tube 104. Specifically, a numerical value that allows the temperature of the optical panel 111 to be relatively evaluated is calculated as an assumed panel temperature, and light emission intervals, charging current, and the like are controlled based on the calculation result. When the discharge tube 104 emits light for the first time in step S308 in Fig. 3, the microcomputer 101 starts this process in parallel with the light emission process in Fig. 3.

[0043] In step S501, the microcomputer 101 initializes settings related to continuous light emission control. It reads input information and parameters that have been set in advance, and proceeds to step S502. Note that if the information and parameters have already been read in step S301 of FIG. 3, this step may be omitted.

[0044] In step S502, the microcomputer 101 starts sampling for controlling continuous light emission. Every time a predetermined sampling time has elapsed, the calculations in steps S503 to S511, which will be described later, are performed. In the following explanation, the calculations during one sampling are explained, and the calculations are repeated every time a predetermined sampling time has elapsed until the heat dissipation time has elapsed or a reset process is performed until the calculation result becomes the same as the initial state. After starting sampling, the process proceeds to step S503.

[0045] In step S503, the microcomputer 101 performs a light emission energy NL calculation process to calculate the light emission energy NL emitted during this sampling. The light emission energy NL is calculated based on the voltage information of the main capacitor 102d, the light emission value information of the discharge tube 104 obtained from the photodiode 106, or the light emission command information from the camera body. The light emission energy NL calculation process will be described in detail later with reference to the flowchart of FIG. 7. After calculating the light emission energy NL, it is stored in the RAM included in the microcomputer 101, and the process proceeds to step S504.

[0046] In step S504, the microcomputer 101 calculates a control temperature addition amount Tfu. The control temperature addition amount Tfu will be described later. After calculating the control temperature addition amount Tfu, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S505. In step S505, the microcomputer 101 calculates a control progress temperature Tfd. The control progress temperature Tfd will be described later. After calculating the control progress temperature Tfd, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S506. In step S506, the microcomputer 101 calculates a control temperature subtraction amount Tfa. The control temperature subtraction amount Tfa will be described later. After calculating the control temperature subtraction amount Tfa, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S507. In step S507, the microcomputer 101 calculates a control temperature Tf. The control temperature Tf will be described later. After calculating the control temperature Tf, the calculation result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S508. Note that every time the control temperature Tf is calculated in step S507, the cooling unit drive control process shown in FIG.

[0047] In step S508, the microcomputer 101 performs a control stage determination process for the panel. The control stage is a stage for setting the shortest light emission interval when continuous light emission is performed in the lighting device 100, and multiple stages are provided including a warning stage, which is the highest control stage. The shortest light emission interval is set to be longer as the control stage increases. Details of the control stage determination process for the panel will be described later using the flowchart in FIG. 9. After the control stage determination process for the panel, the determination result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S509.

[0048] In step S509, the microcomputer 101 calculates a panel temperature counter Cp. The panel temperature counter Cp will be described later. After calculating the panel temperature counter Cp, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S510. In step S510, the microcomputer 101 calculates an internal temperature counter Ci. The internal temperature counter Ci will be described later. After calculating the internal temperature counter Ci, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S511. In step S511, the microcomputer 101 calculates an internal cooling amount Fi. The internal cooling amount Fi will be described later. After calculating the internal cooling amount Fi, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S512.

[0049] In step S512, the microcomputer 101 compares the zoom position at the last light emission in this sampling with the zoom position at the previous sampling. If the comparison shows that the zoom position has not changed, the process proceeds to step S514. Furthermore, if the zoom position change process was performed in step S513 in the previous sampling and a bit was set indicating that the zoom position was changed, the bit is cleared. On the other hand, if the comparison in step S512 shows that the zoom position has changed, the process proceeds to step S513.

[0050] In step S513, the microcomputer 101 performs a zoom position change process. Details of the zoom position change process will be described later with reference to the flowchart in FIG. 10. After the zoom position change process, the result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S514. In step S514, the microcomputer 101 stores various calculation results and the light emission energy NL in the RAM included in the microcomputer 101, and then the process proceeds to step S515. If these are already stored in the RAM, this step may be omitted.

[0051] In step S515, the microcomputer 101 checks whether the control temperature Tf and other calculation results have returned to the initial state set in step S501. If they have returned to the initial state, the process proceeds to step S516, and if they have not returned to the initial state, the process returns to step S503 and starts the next sampling. In step S516, the microcomputer 101 ends the sampling started in step S502 and ends this process.

[0052] Next, the process for controlling continuous light emission for the discharge tube (step S312) in the lighting device 100 will be described with reference to the flowchart in Fig. 6. This process is for suppressing a rise in temperature of the discharge tube 104 due to the influence of heat generated by the light emission of the discharge tube 104. Specifically, a numerical value that allows the temperature of the discharge tube 104 to be relatively evaluated is calculated as an assumed discharge tube temperature, and light emission intervals, charging current, and the like are controlled based on the calculation result. When the discharge tube 104 emits light for the first time in step S308 in Fig. 3, the microcomputer 101 starts this process in parallel with the light emission process in Fig. 3 and the process for controlling continuous light emission for the panel in Fig. 5.

[0053] In step S601, the microcomputer 101 initializes settings related to continuous light emission control. It reads input information and parameters that have been set in advance, and proceeds to step S602. Note that if the information and parameters have already been read in step S301 of FIG. 3, this step may be omitted.

[0054] In step S602, the microcomputer 101 starts sampling for controlling continuous light emission. Every time a predetermined sampling time has elapsed, the microcomputer 101 performs the calculations in steps S603 to S612, which will be described later. In the following explanation, the calculations in one sampling are explained, and the calculations are repeated every time a predetermined sampling time has elapsed until the heat dissipation time has elapsed or a reset process is performed until the calculation result becomes the same as the initial state. After starting sampling, the process proceeds to step S603. In step S603, the microcomputer 101 performs a light emission energy NL calculation process for calculating the light emission energy NL emitted during this sampling. This process is the same as step S503, and may be omitted if step S503 has been executed. After calculating the light emission energy NL, the light emission energy NL is stored in a RAM included in the microcomputer 101, and the process proceeds to step S604.

[0055] In step S604, the microcomputer 101 calculates a control temperature addition amount Tfux. The control temperature addition amount Tfux will be described later. After calculating the control temperature addition amount Tfux, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S605. In step S605, the microcomputer 101 calculates a control progress temperature Tfdx. The control progress temperature Tfdx will be described later. After calculating the control progress temperature Tfdx, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S606. In step S606, the microcomputer 101 calculates a control temperature subtraction amount Tfax. The control temperature subtraction amount Tfax will be described later. After calculating the control temperature subtraction amount Tfax, the calculation result is stored in a RAM included in the microcomputer 101, and the process proceeds to step S607. In step S607, the microcomputer 101 calculates a control temperature Tfx. The control temperature Tfx will be described later. After calculating the control temperature Tfx, the calculation result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S608.

[0056] In step S608, microcomputer 101 performs a discharge tube control stage determination process. The control stage is a stage for setting the shortest light emission interval when continuous light emission is performed in lighting device 100, and multiple stages are provided including a warning stage, which is the highest control stage. The shortest light emission interval is set to be longer as the control stage increases. Details of the discharge tube control stage determination process will be described later using the flowchart in FIG. 14. After the discharge tube control stage determination process, the determination result is stored in the RAM included in microcomputer 101, and the process proceeds to step S609.

[0057] In step S609, the microcomputer 101 calculates the discharge tube temperature counter Cx. The discharge tube temperature counter Cx will be described later. After calculating the discharge tube temperature counter Cx, the microcomputer 101 stores the calculation result in the RAM included in the microcomputer 101, and proceeds to step S610. In step S610, the microcomputer 101 calculates the internal temperature counter Cix. The internal temperature counter Cix will be described later. After calculating the internal temperature counter Cix, the microcomputer 101 stores the calculation result in the RAM included in the microcomputer 101, and proceeds to step S611. In step S611, the microcomputer 101 calculates the internal cooling amount Fix. The internal cooling amount Fix will be described later. After calculating the internal cooling amount Fix, the microcomputer 101 stores the calculation result in the RAM included in the microcomputer 101, and proceeds to step S612. In step S612, the microcomputer 101 stores various calculation results and the light emission energy NL in the RAM included in the microcomputer 101, and proceeds to step S613. If these are already stored in the RAM, this step may be omitted.

[0058] In step S613, the microcomputer 101 checks whether the control temperature Tfx and other calculation results have returned to the initial state set in step S601. If they have returned to the initial state, the process proceeds to step S614, and if they have not returned to the initial state, the process returns to step S603 and starts the next sampling. In step S614, the microcomputer 101 ends the sampling started in step S602 and ends this process.

[0059] Unlike the continuous light emission process for the panel, the zoom position change process is omitted in the continuous light emission control process for the discharge tube in Fig. 6. This is because the heat generated by the light emission of the discharge tube itself is less affected by the zoom position, but the zoom position change process may be executed without being omitted in the continuous light emission control process for the discharge tube.

[0060] Next, the light emission energy NL calculation process (steps S503 and S603) will be described with reference to the flowchart of Fig. 7. In this process, the light emission energy NL is calculated from the voltage information of the main capacitor 102d.

[0061] In step S701, the microcomputer 101 acquires information on the pre-flash voltage bVCM from the A / D converted value of the main capacitor 102d. After acquiring the pre-flash voltage bVCM, the process proceeds to step S702. In step S702, the microcomputer 101 acquires information on the post-flash voltage aVCM from the A / D converted value of the main capacitor 102d. After acquiring the post-flash voltage aVCM, the process proceeds to step S703.

[0062] In step S703, the microcomputer 101 calculates the electrical energy EC using the pre-emission voltage bVCM acquired in step S701 and the post-emission voltage aVCM acquired in step S702. The electrical energy EC is calculated by the following formula (1). EC=(bVCM 2 -aVCM 2 ) / Os ···(1)

[0063] From the formula (1), the output range of the electric energy EC is adjusted by the gain Os. After the electric energy EC is calculated, the process proceeds to step S704.

[0064] In step S704, the microcomputer 101 calculates the light emission energy NL to be used in the calculation formula used in the continuous light emission control process for the panel and the continuous light emission control process for the discharge tube, which will be described later, by converting the weight value. The light emission energy NL is calculated by the following approximate formula (2) according to the configuration of the lighting device 100, etc. NL = α × EC + β (2)

[0065] The coefficients α and β are adjusted based on the measurement data. After calculating the light emission energy NL, the result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S705.

[0066] In step S705, the microcomputer 101 determines whether the main sampling is continuing (whether it is within the main sampling time) or has ended. If the main sampling is continuing, the process returns to step S701, and if it has ended, the process proceeds to step S706.

[0067] In step S706, the microcomputer 101 adds up the light energy NL emitted within this sampling time and updates the light energy NL. If light is emitted multiple times (z) within this sampling time, and the light energies calculated in step S704 are NL1, NL2, ..., NLz, the updated light energy NL is calculated by the following formula (3). NL=NL1+NL2+NL3+···NLz···(3)

[0068] In calculating the light emission energy NL, although the pre-flash and main flash are treated as a series of flashes in step S309, the pre-flash is also considered as an individual flash and is added up using formula (3). If no flash is emitted within the sampling time, the value of the light emission energy NL added up in step S706 will be 0. After updating the light emission energy NL, the result is stored in the RAM included in the microcomputer 101, the light emission energy NL calculation process ends, and the process proceeds to step S504.

[0069] Next, various calculation expressions (steps S504 to S507 and steps S509 to S511) used in the panel continuous light emission control process of FIG. 5 will be described with reference to FIG. 8. FIG. 8 is a diagram showing a heat transfer model of the light-emitting unit 100b. FIG. 8(a) is a diagram showing heat radiation to the optical panel 111 when the discharge tube 104 emits light. FIG. 8(b) is a diagram showing heat transfer from the internal space of the heated light-emitting unit 100b to the optical panel 111 after the discharge tube 104 emits light. FIG. 8(c) is a diagram showing heat transfer when the heated optical panel 111 dissipates heat to the external space after the discharge tube 104 emits light. FIG. 8(d) is a diagram showing heat transfer when the optical panel 111 heated by the light emission of the discharge tube 104 dissipates heat by air blown by the cooling unit 117. FIG. 8(e) is a diagram showing heat transfer to the internal space of the light-emitting unit 100b when the discharge tube 104 emits light. FIG. 8(f) is a diagram showing heat transfer when heat is released from the internal space of the heated light emitting unit 100b to the external space through the exterior.

[0070] 8(a), the optical panel 111 is heated by thermal radiation when the discharge tube 104 emits light. If this amount of heat is the amount of radiant heat Rh, then the following formula (4) is obtained using the above-mentioned light emission energy NL. Rh = NL / Rhc (4)

[0071] Rhc denotes a radiant heating coefficient. Since the optical panel effective range and the influence of heat radiation from the discharge tube 104 differ for each zoom position of the optical panel 111, the radiant heating amount Rh is calculated by setting the radiant heating coefficient Rhc for each zoom position.

[0072] 8(b), after the discharge tube 104 emits light, heat is transferred from the internal space of the heated light-emitting part 100b to the optical panel 111 with a time lag from the point in time when the above-mentioned heat radiation occurs. If this is the amount of heat transferred, Hh, it can be calculated by the following formula (5). Hh=(preCi-preCp) / Hhc (5)

[0073] Ci indicates an internal temperature counter, Cp indicates a panel temperature counter, and the prefix "pre" indicates a result calculated at the previous sampling time or more. Hhc indicates a heat transfer coefficient when heat in the internal space of the light-emitting unit 100b is transferred to the optical panel 111.

[0074] 8(c), the optical panel 111 is heated and simultaneously dissipates heat. If the amount of heat dissipated from the optical panel 111 to the outside is a panel heat dissipation amount Fp, it can be calculated by the following formula (6). Fp = (preCp - preT) / Fhc (6)

[0075] T indicates the environmental temperature or a counter that serves as a substitute for the environmental temperature, and Fhc indicates the heat transfer coefficient when heat is dissipated from the optical panel 111.

[0076] 8(d), the optical panel 111 is cooled by air blown by the cooling unit 117. If the amount of heat forcibly cooled by the cooling unit 117 to the optical panel 111 is taken as a forced cooling heat amount Ap, it can be calculated by the following formula (7). Ap=(Af×Dt×Afc) / Fhc (7)

[0077] Af is the cooling flow rate, Dt is the operating output, and Afc is the conversion coefficient. In addition to the above, heat conduction with the exterior is also considered, but since the contact area is small and sufficiently small compared to the heat transfer when the discharge tube 104 emits light, this is omitted in this embodiment.

[0078] Next, the internal temperature counter Ci shown in equation (5) is calculated.

[0079] 8(e), the internal space of the light-emitting unit 100b is heated by heat transfer when the discharge tube 104 emits light. If this amount of heat is the calorific value Hv, then the following formula (8) is obtained using the light emission energy NL. Hv = (NL × CS) / Cic (8)

[0080] Cic indicates the internal temperature coefficient, which is a conversion coefficient from the light emission energy NL to the heat generation amount Hv. CS indicates the conversion gain, which has the function of adjusting the deviation at the time of conversion to the heat generation amount Hv, which changes depending on the temperature of the internal space of the light-emitting unit 100b.

[0081] 8(f), the internal space of the heated light-emitting unit 100b dissipates heat. If the amount of heat dissipated to the external space through the exterior is the internal cooling amount Fi, it can be calculated by the following formula (9). F = (preCi - preT) / Fic (9)

[0082] Fic denotes the internal cooling coefficient.

[0083] The internal temperature counter Ci shown in equation (5) is calculated by the following equation (10). Ci=preCi+preHv-preFi-preAp / Cr (10)

[0084] Ap indicates the amount of forced cooling heat, and Cr indicates the contribution rate of preAP to the internal temperature counter Ci.

[0085] Moreover, the panel temperature counter Cp shown in the formula (5) is calculated by the following formula (11). Cp=preCp+Rh+Hh-Fp-Ap (11)

[0086] This makes it possible to calculate the heat transfer heat amount Hh using equation (5).

[0087] Next, an estimated temperature of the optical panel 111 (hereinafter referred to as estimated panel temperature) is calculated using the panel temperature counter Cp calculated by equation (11) and the environmental temperature T. If the estimated panel temperature is Tps, it can be calculated by the following equation (12). Tps = T + Cp / Tc (12)

[0088] Tc is a temperature conversion coefficient. If the environmental temperature T is known, the expected panel temperature at that time can be calculated from equation (12). In this embodiment, it is assumed that continuous light emission control is realized while reducing costs without using a known temperature sensor, and in order to simplify the control, the following calculations are performed with T=0.

[0089] In order to perform calculations related to the continuous light emission control process, the formula (12) is expanded and rearranged to obtain the following formula (13). Tf=NL / (Rhc×Tc)+(1 / Tc-2 / (Hhc×Tc))×preCp+preCi / (Hhc×Tc)-(Af×Dt×Afc) / (Hhc×Tc) ···(13) (∵Tf=Tps-T,Hhc=Fhc,T=0)

[0090] Tf indicates a control temperature and is the relative temperature of the optical panel 111, and at the same time, it also plays the role of a light emission counter and is used to determine the control described below. If the first term on the right side of equation (13) is the control temperature addition amount Tfu, the second and third terms on the right side are the control progress temperature Tfd, and the fourth term on the right side is the control temperature subtraction amount Tfa, then the following equation (14) is obtained.

[0091]

number

[0092] The panel temperature counter for the next sampling is indicated by preCp', and the internal temperature counter is indicated by preCi'. preCp'=(1-2 / Hhc)×preCp+preCi / Hhc+NL / Rhc-(Af×Dt×Afc) / Hhc ···(15) preCi'=preCi+(preNL×CS) / Cic-preFi-(Af×preDt×Afc) / (Hhc×Cr) ···(16) preFi = preCi / Fic (17)

[0093] The preCp' and preCi' calculated by the equations (15) and (16) are fed back as preCp and preCi after conversion processing at the next sampling.

[0094] The above are the calculation formulas used in the panel continuous light emission control process. That is, in step S504, the first formula of formula (14) is used, in step S505, the second formula of formula (14), in step S506, the third formula of formula (14), and in step S507, the fourth formula of formula (14). In addition, in step S509, calculation is performed using formula (15), in step S510, formula (16), and in step S511, formula (17). In addition, in formulas (15) to (17), the panel temperature counter, the internal temperature counter, and the amount of internal cooling heat are calculated, respectively, for feedback to the next sampling. This makes it possible to calculate the heat dissipation time, the amount of airflow determined by the operating output Dt of the cooling unit 117 and the corresponding cooling flow rate Af, and the expected panel temperature based on the temperature difference between the optical panel 111, the internal space of the light emitting unit 100b, and the like.

[0095] Next, the control level determination process (step S508) during the panel continuous light emission control process will be described with reference to the flowchart of FIG.

[0096] In step S901, the microcomputer 101 acquires the zoom position at the time of emission in this sampling from the zoom detection unit 115a, stores the result in the RAM included in the microcomputer 101, and then proceeds to step S902. In step S902, the microcomputer 101 reads from the RAM included in the microcomputer 101 a plurality of determination thresholds that are set corresponding to the zoom position acquired in step S901, and proceeds to step S903. Here, the plurality of determination thresholds indicate minimum temperatures for different control stages.

[0097] In step S903, the microcomputer 101 determines the control stage based on the control temperature Tf obtained in step S508 and the determination threshold read in step S902. Specifically, the control temperature Tf is compared in order from the highest temperature control stage to determine whether it exceeds the determination threshold, and when the control temperature Tf exceeds the determination threshold as a result of the comparison, it is determined that the control stage has the determination threshold as the lowest temperature. After that, the determined control stage is stored in the RAM included in the microcomputer 101, and the process proceeds to step S904. In the control process for each control stage, if the electrical energy calculation obtained in step S703 or the light emission energy NL obtained in step S704 exceeds an arbitrary threshold, control is performed to delay the determination of the next charging completion (step S307) by an arbitrary time after the light emission operation.

[0098] In step S904, the microcomputer 101 updates the current control stage to the control stage determined in step S903, and updates the related parameters. By updating the control stage, the shortest light emission interval is changed. If there is no change from the current control stage, this step may be omitted. After updating the control stage, the result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S905.

[0099] In step S905, the microcomputer 101 determines whether the control stage updated in step S904 is the warning stage. If the control stage has not been updated in step S904 and step S905 is omitted, step S905 may be omitted. If it is in the warning stage, the process proceeds to step S906, and if it is not in the warning stage, the control stage determination process in FIG. 9 is terminated and the process proceeds to step S509. If it is not in the warning stage and the sampling time has been updated in step S906 to a determination process time for the warning stage, which will be described later, the sampling time is returned to the sampling time set in step S502.

[0100] In step S906, the microcomputer 101 updates the sampling time set in step S502 to the judgment processing time for the warning stage. Here, the judgment processing time is a time longer than the sampling time set in step S502. This is because if the warning display in the next step S907 is updated with the sampling time set in step S502, a phenomenon like chattering on the display may occur, making the display difficult to see and possibly causing the user to mistake it for a malfunction of the lighting device 100. After applying the judgment processing time for the warning stage, the result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S907.

[0101] In step S907, the microcomputer 101 executes display control to display a warning display of the corresponding warning level on the display unit 114, generates continuous light emission control once after the next light emission operation, and then ends the control level determination process and proceeds to step S509. In this continuous light emission control, control is performed to delay the determination of the next charging completion (step S307) after the light emission operation for a time set according to the control level determined in step S903. In other words, light emission is limited and the time from the execution of the first light emission operation to the execution of the second light emission operation is controlled.

[0102] Next, the zoom position change process (step S513) during the continuous light emission control process will be described with reference to the flowchart of FIG.

[0103] In step S1001, the microcomputer 101 reads the judgment threshold of the control temperature Tf of the control stage determined in step S508 at the zoom position before the zoom position is changed. After reading the judgment threshold before the change, the process proceeds to step S1002. In step S1002, the microcomputer 101 reads the judgment threshold of the control temperature Tf of the control stage determined in step S508 at the zoom position after the zoom position is changed. After reading the judgment threshold after the change, the process proceeds to step S1003.

[0104] In step S1003, microcomputer 101 performs conversion processing on panel temperature counter preCp, which is the calculation result of step S509, using the ratio of the judgment thresholds read in steps S1001 and S1002. This is because the range of the control stage differs for each zoom position. If the converted panel temperature counter is denoted by preCp', preCp' can be calculated by the following equation (18) where FPZ is the judgment threshold before conversion and FAZ is the judgment threshold after conversion. preCp'=preCp×FAZ / FPZ (18)

[0105] The preCp' calculated by the formula (18) is fed back to the next sampling as preCp after conversion processing, and the conversion processing is performed immediately when the zoom position change operation is performed. After the conversion processing in step S1003, the calculation result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S1004.

[0106] In step S1004, the microcomputer 101 indicates the internal temperature counter, which is the calculation result in step S510, as preCi', and performs a conversion process on preCi' based on the ratio of the determination thresholds read in steps S1001 and S1002. Then, preCi' is calculated by the following formula (19). preCi'=preCi×FAZ / FPZ (19)

[0107] The preCi' calculated by the formula (19) is fed back as the converted preCi to the next sampling, and the conversion process is performed immediately when the zoom position is changed. After the conversion process in step S1004, the calculation result is stored in the RAM included in the microcomputer 101, and the process proceeds to step S1005.

[0108] In step S1005, the microcomputer 101 updates the judgment threshold before the change with the judgment threshold after the change, and stores it in the RAM included in the microcomputer 101. This makes it possible to use the current judgment threshold as the judgment threshold before the change in the next sampling. Also, a bit indicating that the zoom position has been changed is set. If this bit is set, the control stage judgment process in step S508 is not performed. This is because feedback is performed in the panel continuous light emission control process, and immediately after the zoom position is changed, the control temperature Tf is calculated using the panel temperature counter Cp and the internal temperature counter Ci calculated at the previous zoom position. This is because if a control stage judgment is performed at that stage, the control stage may temporarily deviate from the normal value. After storing the bit in the RAM included in the microcomputer 101, the zoom position change process in FIG. 10 is terminated.

[0109] Next, the cooling unit drive control process that starts in conjunction with the continuous light emission control process of Fig. 5 will be described with reference to the flowchart of Fig. 11. The cooling unit drive control process is a process for cooling the optical panel 111 by blowing air from the cooling unit 117 to protect the light emitting unit 100b, particularly the optical panel 111, from the effects of heat generated by the light emission of the discharge tube 104. By determining the operating output Dt during air blowing based on the control temperature Tf, it is possible to control the operation output Dt to increase the cooling efficiency when the temperature of the optical panel 111 is high, and to reduce the operating output Dt to suppress drive noise and power consumption when the temperature of the optical panel 111 is low.

[0110] When the control temperature Tf is calculated in step S507 in FIG. 5, the microcomputer 101 starts the cooling unit drive control process shown in FIG.

[0111] In step S1101, the microcomputer 101 reads the result of the control temperature Tf calculated in step S507 from the RAM. After reading the control temperature Tf, the process proceeds to step S1102. In step S1102, the microcomputer 101 reads a plurality of cooling unit drive control thresholds for determining the operation output Dt of the cooling unit 117 from the RAM included in the microcomputer 101, and proceeds to step S1103. In step S1103, the microcomputer 101 determines which cooling control stage the control temperature Tf read in step S1101 is in between the plurality of cooling unit drive control thresholds read in step S1102, and determines the operation output Dt corresponding to the determined cooling control stage. Specifically, information indicating the value of the operation output Dt for each cooling control stage is held in advance in the ROM of the microcomputer 101, and this determination is made using the information. After determining the operation output Dt, the result of the operation output Dt is stored in the RAM included in the microcomputer 101, and the process proceeds to step S1104. In step S1104, the microcomputer 101 updates the drive control settings to drive the cooling unit 117 with the operating output Dt determined in step S1103. After updating the drive control settings, the microcomputer 101 stores the setting results in the RAM included in the microcomputer 101, and the process proceeds to step S1105.

[0112] In step S1105, microcomputer 101 checks whether cooling unit 117 is operating at the operation output set in step S1104 and whether there is an abnormality in the operation output. If there is no abnormality in the operation output, the cooling unit drive control process in Fig. 11 is terminated and the process returns to step S302, and if there is an abnormality in the operation output, the process proceeds to step S1106.

[0113] In step S1106, the microcomputer 101 determines that the cooling unit 117 cannot operate normally due to a malfunction or the like, stops driving the cooling unit 117, and then updates the settings of the calculation parameters. After updating the settings of the calculation parameters, the cooling unit drive control process in FIG. 11 is terminated.

[0114] In step S1103, the operation output Dt of the cooling unit 117 may be determined based on the judgment threshold used in the control stage judgment in step S903, instead of the cooling unit drive control threshold in step S1102. This makes it difficult to fine-tune the operation output Dt, but it makes it possible to eliminate the need for a table of cooling unit drive control thresholds and to link the shortest light emission interval and the operation output Dt for each control stage.

[0115] Next, the relationship between the assumed panel temperature and the actual temperature measurement value of the optical panel 111 in this embodiment will be described with reference to the graph in Fig. 12. Fig. 12 is a graph showing the actual temperature measurement value of the optical panel 111 and the assumed panel temperature. As described above, the assumed panel temperature can be calculated by the formula (12).

[0116] 12 shows the temperature result of the optical panel 111 when the driving of the cooling unit 117 is stopped from the input unit 113 after 150 seconds have elapsed after the end of continuous light emission while the cooling unit 117 is driven. In the example shown in FIG. 12, the temperature of the optical panel 111 rises to about 88°C by continuous light emission from the actual measurement value shown by the dotted line, and then drops to about 72°C before the driving of the cooling unit 117 is stopped. However, after the cooling unit 117 is stopped, the temperature rises again to about 100°C due to the heat of the internal space of the light-emitting unit 100b heated by the discharge tube 104. The assumed panel temperature Tps of the formula (12) shown by the solid line can be assumed by the series of processes and calculations described above, which are the temperature change of the optical panel 111 caused by the cooling unit 117 being stopped from being driven. That is, in this embodiment, it is possible to realize continuous light emission control while reducing costs without using a known temperature sensor or the like.

[0117] Next, various arithmetic expressions (steps S604 to S607 and steps S609 to S611) used in the discharge tube continuous light emission control process in FIG. 6 will be described with reference to FIG.

[0118] FIG. 13 is a diagram showing a heat transfer model of the discharge tube 104, and is a cross-sectional view of the discharge tube 104. The discharge tube 104 emits light and generates heat when the discharge current 104a flows from the anode to the cathode inside the discharge tube. FIG. 13(a) is a diagram showing heat radiation from the discharge current 104a to the discharge tube glass part 104b. FIG. 13(b) is a diagram showing heat transfer from the hollow internal space of the discharge tube 104 heated by the discharge current 104a to the discharge tube glass part 104b. FIG. 13(c) is a diagram showing heat transfer when the discharge tube 104 emits light and then dissipates heat from the heated discharge tube glass part 104b to the external space. FIG. 13(d) is a diagram showing heat transfer when the discharge tube glass part 104b heated by light emission dissipates heat due to the influence of the air blown by the cooling part 117. In this embodiment, the difference between the inner diameter and the outer diameter of the discharge tube 104 is assumed to be small, and the influence of heat transfer inside the glass of the tube is ignored for the sake of simplicity of explanation.

[0119] 13(a), the discharge tube glass part 104b is heated by thermal radiation of the discharge current 104a. If this heat amount is the radiant heat amount Rhx, it is expressed by the following formula (20) using the above-mentioned light emission energy NL. Rhx = NL × Sx / Rhcx (20)

[0120] Rhcx indicates a radiation heating coefficient, and Sx indicates a light emission time coefficient. The light emission time coefficient Sx is a coefficient that takes a value larger than 1 in the case of flat light emission when the light emission time coefficient Sx is set to 1 in the case of flash light emission. This indicates that even if the light emission energy NL consumed by the light emission operation of the discharge tube 104 is the same, the longer the time that the discharge current 104a flows, the easier it is for the temperature of the discharge tube glass part 104b to rise. In addition, in the above-mentioned formula (4), since the distance from the discharge tube 104 to the optical panel 111 changes due to the zoom operation, the effect on the heat radiation is expressed by the variable Rhc. In contrast, since the distance from the discharge tube glass part 104b to the discharge current 104a is not affected by the zoom position, the radiation heating coefficient Rhcx may be a constant. In addition, since the diameter of the discharge tube of the illumination device used in a general imaging device is several millimeters, the distance from the discharge current 104a to the discharge tube glass part 104b may be set to 1, ignoring the attenuation of radiation heat due to the distance.

[0121] As shown in Fig. 13(b), after the discharge tube 104 emits light, heat is transferred from the heated internal space of the discharge tube to the discharge tube glass part 104b with a time lag from the point in time when the above-mentioned heat radiation occurs. If this is the amount of heat transferred, Hhx, it can be calculated by the following formula (21). Hhx=(preCix-preCx) / Hhcx (21)

[0122] Cix indicates the internal temperature counter, Cx indicates the discharge tube temperature counter. The prefix "pre" indicates the result calculated at the previous sampling time or more. Hhcx indicates the heat transfer coefficient when the heat in the internal space of the discharge tube 104 is transferred to the discharge tube glass part 104b.

[0123] 13(c), the discharge tube glass part 104b is heated and at the same time dissipates heat. If the amount of heat dissipated from the discharge tube glass part 104b to the outside is the discharge tube heat dissipation amount Fx, it can be calculated by the following formula (22). Fx=(preCx-preTx) / Fhcx (22)

[0124] Tx indicates the spatial environmental temperature around the discharge tube 104 or a counter that serves as a substitute for it, and Fhcx indicates the heat transfer coefficient when heat is dissipated from the discharge tube glass part 104b.

[0125] 13(c), the heat of the heated discharge tube glass part 104b is transferred to the entire discharge tube glass part 104b and dissipated to the external space from the entire surface. This is because the heat distribution of the discharge tube glass part 104b is not uniform depending on the position where the discharge current 104a is generated. With reference to formula (9), if the outer shell is regarded as the entire discharge tube glass part 104b, and the amount of heat dissipated to the external space through the outer shell is the internal cooling amount Fix, it can be calculated by the following formula (23). Fix=(preCi-preTx) / Ficx ···(23)

[0126] Fix indicates the internal cooling coefficient.

[0127] 13(d), the discharge tube glass part 104b is cooled by circulating the air in the internal space of the light-emitting part 100b by the air blown by the cooling part 117. If the amount of heat forcibly cooled by the cooling part 117 in the discharge tube glass part 104d is the amount of forced cooling heat Ax, it can be calculated by the following formula (24). Ax=(Afx×Dt×Afcx) / Fhcx ···(24)

[0128] Afx is the cooling flow rate, Dt is the operating output, and Afcx is the conversion coefficient. Note that in a configuration in which the discharge tube 104 is not included in the air circulation path of the cooling unit 117, or in a configuration in which convection does not occur in the internal space of the light-emitting unit 100b, the term in formula (24) may be ignored.

[0129] Next, the internal temperature counter Cix shown in formula (21) is calculated. As shown in Fig. 13(b), the internal space of the discharge tube 104 is heated by heat transfer when the discharge tube 104 emits light. If this heat amount is the heat generation amount Hv, the following formula (25) is obtained using the light emission energy NL. Hvx = (NL × CSx) / Cicx (25)

[0130] Cicx indicates an internal temperature coefficient, which is a conversion coefficient from the light emission energy NL to the calorific value Hvx. CSx indicates a conversion gain, which has a function of adjusting the deviation at the time of conversion to the calorific value Hvx, which changes depending on the temperature of the internal space of the discharge tube 104.

[0131] The internal temperature counter Cix shown in equation (21) is calculated by the following equation (26). Cix=preCix+preHvx-preFix-preApx / Crx (26)

[0132] Apx indicates the amount of forced cooling heat, and Crx indicates the contribution rate of preAPx to the internal temperature counter Cix.

[0133] Moreover, the discharge tube temperature counter Cx shown in equation (21) is calculated by the following equation (27). Cx=preCx+Rhx+Hhx-Fx-Apx (27)

[0134] This makes it possible to calculate the heat transfer heat amount Hhx using equation (21).

[0135] Next, the assumed temperature of the discharge tube glass part 104b (hereinafter referred to as the assumed discharge tube temperature) is calculated using the discharge tube temperature counter Cx and the internal environment temperature Tx calculated by the formula (27). If the assumed discharge tube temperature is Txs, it can be calculated by the following formula (28). Txs = Tx + Cx / Tcx (28)

[0136] Tcx indicates a temperature conversion coefficient. If the internal environmental temperature Tx is known, the expected discharge tube temperature at that time can be calculated from formula (28). In this embodiment, it is assumed that continuous light emission control is realized while reducing costs without using a known temperature sensor, etc., and in order to simplify the control, the following calculations are performed with Tx=0.

[0137] In order to perform calculations related to the continuous light emission control process, equation (28) is expanded and rearranged to obtain the following equation (29). Tfx=NL×Sx / (Rhcx×Tcx)+(1 / Tcx-2 / (Hhc×Tcx))×preCx+preCix / (Hhcx×Tcx)-(Af×Dt×Afc) / (Hhcx×Tcx) ···(29) (∵Tfx=Txs-Tx,Hhcx=Fhcx,Tx=0)

[0138] Tfx indicates the control temperature, which is the relative temperature of the discharge tube glass portion 104b, and at the same time, it also has the role of a light emission counter and is used to judge the control described later.

[0139] Here, if the first term on the right side of equation (29) is the control temperature addition amount Tfux, the second and third terms on the right side are the control progress temperature Tfdx, and the fourth term on the right side is the control temperature subtraction amount Tfax, the following equation (30) is obtained.

[0140]

number

[0141] The discharge tube temperature counter for the next sampling is indicated by preCx', and the internal temperature counter is indicated by preCix'. preCx'=(1-1 / Hhcx)×preCx+preCix / Hhcx+NL×Sx / Rhcx-(Af×Dt×Afc) / Hhcx (31) preCix'=preCix+(preNL×CSx) / Cicx-(Af×preDt×Afc) / (Hhc×Cr) ···(32) preFix=preCix / Ficx (33)

[0142] The preCx' and preCix' calculated by equations (31) and (32) are fed back as preCx and preCix after conversion processing at the next sampling.

[0143] The above are the calculation formulas used in the discharge tube continuous light emission control process. That is, in step S604, the first formula of formula (30) is used, in step S605, the second formula of formula (30), in step S606, the third formula of formula (30), and in step S607, the fourth formula of formula (30). In addition, in step S609, calculation is performed using formula (31), in step S610, formula (32), and in step S611, formula (33). In addition, in formulas (31) to (33), the discharge tube temperature counter, the internal temperature counter, and the internal cooling heat quantity are calculated, respectively, for feedback to the next sampling. This makes it possible to calculate the heat dissipation time, the airflow amount determined by the operating output Dt of the cooling unit 117 and the corresponding cooling flow rate Afx, and the assumed discharge tube temperature based on the temperature difference between the internal space of the discharge tube 104 and the light emitting unit 100b, etc.

[0144] Next, the discharge tube control stage determination process (step S608) during the continuous light emission control process will be described with reference to the flowchart of FIG.

[0145] In step S1401, the microcomputer 101 acquires the light emission operation setting for light emission in this sampling from the setting in step S301, stores the result in the RAM included in the microcomputer 101, and then proceeds to step S1402. The light emission operation setting in this embodiment indicates an operation setting in which the light emission time varies depending on a single light emission instruction, such as flash emission or flat emission. In step S1402, the microcomputer 101 reads from the RAM included in the microcomputer 101 a number of determination thresholds that are set corresponding to the light emission operation acquired in step S1401, and proceeds to step S903. Here, the multiple determination thresholds indicate thresholds for the control temperature Tfx determined for each light emission operation.

[0146] In step S1403, the microcomputer 101 judges whether or not the control temperature Tfx calculated in step S608 exceeds the judgment threshold read in step S1402. If it exceeds the judgment threshold, the process proceeds to step S1404, and if it does not exceed the judgment threshold, the discharge tube control stage judgment process in FIG. 14 is terminated and the process proceeds to step S609.

[0147] In step S1404, if the determination threshold was exceeded in step S1403, the microcomputer 101 generates continuous light emission control 1 once after the next light emission operation, and then ends the discharge tube control stage determination process and proceeds to step S609. In continuous light emission control 1, while the control temperature Tfx found in step S607 exceeds the determination threshold in step S1403, control is performed to delay the determination of the next charging completion (step S307) after the light emission operation by a predetermined arbitrary time, regardless of the light emission setting. This is due to the fast heat dissipation rate of the discharge tube glass part 104b described later, and even if only a few seconds are provided for the time when the discharge current 104a does not flow, it is possible to control to suppress the temperature rise of the discharge tube 104.

[0148] In addition, when it is necessary to generate the continuous light emission control in step S907 and the continuous light emission control 1 in step S1404, the control for delaying the determination of the next charging completion (step S307) after the light emission operation may be generated once. In that case, it is sufficient to delay the determination by the longer time between the time set according to the control stage determined in step S903 and the predetermined time used in step S1404. In this embodiment, the cooling unit drive control process shown in FIG. 11 is not performed based on the calculation result of the discharge tube control temperature Tfx in step S608 of FIG. 6. This is because, in the configuration of this embodiment, the cooling unit 117 has a flow path configuration aimed at cooling the optical panel 111 and does not actively secure a flow path for the discharge tube 104. In addition, since the heat dissipation speed of the discharge tube glass part 104b described later is fast and the cooling method is by internal circulation of air around the discharge tube 104, it can be said that the influence on the temperature of the discharge tube glass part 104b is small even if the air volume is increased. In the case of a configuration in which the wind from the cooling unit 117 has a cooling effect on the discharge tube 104, a flowchart similar to that of FIG. 11 may be created and the cooling unit operation output may be determined in conjunction with the calculation result of the discharge tube control temperature Tfx.

[0149] Next, the relationship between the assumed panel temperature and the actual temperature measurement value of the discharge tube 104 in this embodiment will be described using the graph in Fig. 15. Fig. 15 is a graph showing the actual temperature measurement value by thermography of the discharge tube glass part 104b and the assumed discharge tube temperature. As described above, the assumed discharge tube temperature can be calculated by the formula (28).

[0150] Figure 15(a) is a temperature graph showing the results when the flash was fired about 20 times per second at 1 / 64th the light output of manual flash firing and stopped firing after about 32 seconds. Figure 15(b) is a temperature graph showing the results when the flash was fired about 18 times per second at 1 / 64th the light output of manual flat firing and stopped firing after about 6 seconds.

[0151] In the example of Fig. 15(a), the actual measurement value shown by the dotted line indicates that the temperature of the discharge tube glass part 104b rises to approximately 430°C after about 32 seconds of continuous light emission. In the example of Fig. 15(b), the actual measurement value shown by the dotted line indicates that the temperature of the discharge tube glass part 104b rises to approximately 490°C after about 6 seconds of continuous light emission. In both Figs. 15(a) and 15(b), the assumed discharge tube temperature shown by the solid line is approximately equal to the actual measurement value.

[0152] Next, the difference in light emission time at the same light intensity between flash emission and flat emission, which are different light emission operation methods, will be described with reference to Fig. 16. Fig. 16 is a graph showing the time axis from when a pulse voltage is applied to discharge tube 104 to when light emission ends, with Fig. 16(a) showing the trigger waveform for flash emission, Fig. 16(b) showing a schematic diagram of a flash emission waveform, and Fig. 16(c) showing a graph showing the integral value of the light receiving current during flash emission. Fig. 16(d) showing the trigger waveform for flat emission, Fig. 16(e) showing a schematic diagram of a flat emission waveform, and Fig. 16(f) showing the integral value of the light receiving current during flat emission. The horizontal axis in each of Figs. 16(a) to (f) is time.

[0153] In Fig. 16(a), trigger circuit 103 receives a trigger waveform of a flash emission instruction from light emission control circuit 105. Then, in Fig. 16(b), after a communication time T has elapsed, discharge tube 104 is excited by application of a pulse voltage from trigger circuit 103. In Fig. 16(c), photodiode 106 integrates the light receiving current received from discharge tube 104 until it reaches a designated integral value. This flash emission time is denoted as S.

[0154] In Fig. 16(d), the trigger circuit 103 receives a trigger waveform of a flat light emission instruction from the light emission control circuit 105. Then, in Fig. 16(e), after a communication time T has elapsed, the discharge tube 104 is excited by applying a pulse voltage from the trigger circuit 103. In Fig. 16(f), the photodiode 106 integrates the light receiving current received from the discharge tube 104 until it reaches a designated integral value. This flat light emission time is indicated as F.

[0155] Note that the integral values ​​shown in Figures 16(c) and 16(f) are the same light receiving current. At this time, the voltage difference before and after light emission calculated in step S703 is the same for flash light emission and flat light emission in Figure 16, and the light emission energy NL is also the same. However, as shown by the flash light emission time S and flat light emission time F in Figure 16, the time during which the discharge tube 104 is excited is longer in the flat light emission.

[0156] As shown in the above Figs. 15 and 16, the excitation time of the discharge tube 104 is different between the flash emission and the flat emission even if the light emission amount is the same. Furthermore, when the flash emission and the flat emission are continuously emitted in a short time, a difference in the excitation time occurs for each emission, so that a difference in the temperature rise rate of the discharge tube glass part 104b occurs as shown in Fig. 15. Therefore, the longer the time that the discharge current 104a flows during light emission, such as in the flat emission compared to the flash emission among the multiple light emission operations, the easier it is for the temperature of the discharge tube glass part 104b to rise. In this embodiment, the difference in the temperature rise of the discharge tube glass part 104b due to this light emission operation is indicated by the light emission time coefficient Sx shown in formula (20). That is, in this embodiment, it is possible to assume the temperature change of the discharge tube glass part 104b according to the light emission operation of the discharge tube 104 by the series of processes and calculations described above.

[0157] In the graph shown in Fig. 15, the temperatures of the discharge tube glass part 104b exceed 400°C, but the judgment threshold of step S1402 in Fig. 14 may be lowered in consideration of the heat resistance temperature of the discharge tube glass part 104b, the temperature range where light emission starts to drop, and the frequency of such a temperature drop. Also, the time for delaying the completion of the next charge (step S307) by the discharge tube continuous light emission control in the above-mentioned step S1404 may be determined in consideration of the heat dissipation rate of the discharge tube glass part 104b. This is because the heat dissipation rate of the discharge tube temperature measurement value shown in Fig. 15 is faster than the heat dissipation rate of the panel temperature measurement value shown in Fig. 12, and because the condition under which the temperature of the discharge tube glass part 104b is likely to rise is high-speed continuous shooting in a short period of time.

[0158] In addition, when setting the non-light emitting time, by expressing the heat dissipation phenomenon of the control temperature Tfx of the discharge tube 104 as a counter for subtraction processing as shown in equation (29) and Figure 15, it is possible to determine the time necessary and sufficient for cooling the discharge tube glass part 104b.

[0159] In the above embodiment, the control for suppressing the temperature rise of the optical panel 111 and the discharge tube 104 by independently processing the panel continuous light emission control process shown in FIG. 5 and the discharge tube light emission control process shown in FIG. 6 has been described. Then, the formulas (4) to (17) required for calculating the assumed panel temperature Tps and the formulas (20) to (33) required for calculating the assumed discharge tube temperature Txs have been described in detail. Among them, the distance between the optical panel 111 and the discharge tube 104 is important as a parameter that greatly affects the calculation of the assumed panel temperature Tps, and the radiant heat amount Rh in formula (4) is set for each zoom position. On the other hand, the time during which the discharge current 104a due to the light emission operation flows is important as a parameter that greatly affects the calculation of the assumed discharge tube temperature Txs, and the light emission time coefficient Sx in formula (20) is set for each light emission operation. That is, the assumed discharge tube temperature Txs is calculated based on the first degree of influence of the heat due to the light emission operation, and the assumed panel temperature Tps is calculated based on the second degree of influence of the heat due to the light emission operation that is different from the first degree of influence.

[0160] The models of the calculation formulas for the assumed panel temperature Tps and the assumed discharge tube temperature Txs take into account thermal radiation, heat transfer heating, heat transfer cooling, and forced cooling, but it is also possible to use simplified calculation formulas by omitting some of them.

[0161] In addition, in this embodiment, the microcomputer 101 has been described as a one-chip IC circuit configuration including a CPU that executes the above-mentioned series of processes and a RAM that stores various information, but is not limited to this. For example, a dedicated control unit, a determination unit, a memory, etc. that execute each of the above-mentioned series of processes may be provided. In addition, the cooling unit 117 has been described as a fan module, but it may be a cooling module having the same function as a pump, etc. In addition, the flowcharts described in this embodiment are merely examples, and various processes may be executed in a different order from the flowcharts described in this embodiment if there is no inconvenience.

[0162] Second embodiment Hereinafter, a second embodiment of the present invention will be described with reference to Fig. 17. This embodiment differs from the first embodiment in the discharge tube control stage determination process, but other aspects are similar to the first embodiment, so description thereof will be omitted.

[0163] In this embodiment, discharge tube control stage determination process 2 shown in FIG. 17 is executed in step S608 of the flowchart shown in FIG.

[0164] Steps S1601 and S1602 are the same processes as steps S1401 and S1402 in Fig. 14, and the description thereof will be omitted. In step S1603, the microcomputer 101 reads the panel control stage determined in step S508, and proceeds to step S1604. In step S1604, the same process as step S1403 in Fig. 14, and the description thereof will be omitted. In step S1605, the microcomputer 101 updates the determination processing time in the same manner as in step S906.

[0165] In step S1606, the microcomputer 101 generates the continuous light emission control 2 once after the next light emission operation, and then ends the discharge tube control stage determination process and proceeds to step S609. In the continuous light emission control 2, while the control temperature Tfx exceeds the determination threshold in step S1604, regardless of the light emission setting, the shortest light emission interval according to the panel control stage updated in step S904 is generated only once after the light emission operation, and the next light emission operation is delayed. In this way, by making the time for delaying the next charging completion by the continuous light emission control (step S307) the same as the time set according to the panel control stage in this embodiment, it is possible to prevent a plurality of control contents from being mixed. That is, in this embodiment, when it is necessary to generate the continuous light emission control in step S907, the time set according to the control stage determined in step S903 is used regardless of whether it is necessary to emit the continuous light emission control 2 in step S1606.

[0166] This allows control to suppress the temperature rise of the optical panel 111 and the discharge tube 104 while maintaining a natural operability when the lighting device 100 is continuously emitting light and continuous light emission control occurs. Also, as shown in Figs. 12 and 15, the assumed discharge tube temperature Tfx has a faster temperature drop rate than the assumed panel temperature Tf. Therefore, even if the continuous light emission control operation is unified with the charge completion delay time by the panel continuous light emission control, it is sufficiently effective as control to suppress the temperature rise of the discharge tube 104. Since the control temperature Tf and control temperature Tfx shown in formula (29) take into account the internal cooling amount and the forced cooling heat amount, which are parameters related to heat dissipation, and the effect of subtraction during this sampling can also be expressed, control to suppress the temperature rise of the optical panel 111 and the discharge tube 104 is possible.

[0167] In the above-described embodiment, the control process of steps S311 and S312 in the light emission process flow chart of FIG. 3 has been described as a control for suppressing a temperature rise of the optical panel 111 and the discharge tube 104 during continuous light emission. However, the target part for suppressing the temperature rise is not limited to the optical panel 111 and the discharge tube 104, and may be an electrical component of the light-emitting unit 100b that is located near the light source and is affected by the heat generated by the discharge tube 104 during light emission operation, or an exterior member. In this case, immediately after step S312, the control temperature of the assumed location is calculated as described in formulas (4) to (19), and a judgment threshold value for the assumed location is set as shown in step S902, thereby enabling control according to the target for which the temperature rise is to be suppressed. In addition, when it is desired to preferentially suppress a temperature rise of any target part of the lighting device 100 other than the optical panel 111 and the discharge tube 104, the control process of steps S311 and S312 may be replaced with a control process of the target part for which the temperature rise is to be preferentially suppressed. In this configuration, the part for which it is desired to suppress temperature rise preferentially is not limited to the light-emitting part 100b, but may also be the main body part 100a. For example, it may be possible to suppress temperature rise preferentially in the battery 200 of the main body part 100a or in the boosting part 102a of the main body part 100a.

[0168] In the above-described embodiment, the difference in temperature rise due to the light-emitting operation of the discharge tube 104 is represented by the light-emitting time coefficient Sx shown in formula (20), but it may be set to a parameter equivalent to the light-emitting time. For example, when the light-emitting body is an LED, the duty ratio of the voltage based on the PWM control by the microcomputer 101 is applied to Sx as a coefficient indicating the time when the LED emits light and does not emit light, making it possible to calculate the difference in temperature rise due to the duty ratio of the LED. Also, when the light-emitting body is an LED, by calculating the temperature of the heat source or its vicinity as the control temperature, it is possible to perform control to suppress the temperature rise without the need to provide a thermometer element around the LED.

[0169] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention.

[0170] The disclosure of this embodiment includes the following configurations and methods.

[0171] (Configuration 1) a first target portion including a light source; A second target portion different from the light source; A light emission control means for controlling a light emission operation of the light source; a calculation means for calculating a first control temperature, which is a relative temperature of the first target part, and a second control temperature, which is a relative temperature of the second target part, based on heat generated by a light emission operation of the light source; a control means for controlling the light emitting operation based on at least one of the first and second control temperatures; The lighting device is characterized in that the calculation means calculates the first control temperature based on a first degree of influence of heat due to the light-emitting operation, and calculates the second control temperature based on a second degree of influence of heat due to the light-emitting operation that is different from the first degree of influence.

[0172] (Configuration 2) 2. The lighting device according to configuration 1, wherein the first degree of influence is a degree of influence depending on at least an amount of light emitted by a light source and a light emission time.

[0173] (Configuration 3) 3. The lighting device according to configuration 1 or 2, wherein the second degree of influence is a degree of influence depending on at least an amount of light emitted by a light source and a distance from the light source.

[0174] (Configuration 4) 4. The lighting device according to any one of configurations 1 to 3, wherein the light source is a discharge tube.

[0175] (Configuration 5) 4. The lighting device according to any one of configurations 1 to 3, wherein the light source is an LED.

[0176] (Configuration 6) 6. The lighting device according to claim 1, wherein the control means controls to limit light emission based on a time period determined according to the first control temperature and the second control temperature.

[0177] (Configuration 7) 7. The lighting device according to claim 1, wherein the first and second influence levels vary depending on a type of light emission operation of the light source.

[0178] (Configuration 8) 8. The lighting device according to claim 1, wherein the control means controls a time period from when a first light-emitting operation is performed until when a second light-emitting operation is performed.

[0179] (Configuration 9) The lighting device described in configuration 8, wherein the control means controls the time from when the first control temperature exceeds a first threshold value to when the second light-emitting operation is performed based on a predetermined time.

[0180] (Configuration 10) The lighting device according to configuration 8, wherein the control means controls a time from when the first light-emitting operation is performed to when the second light-emitting operation is performed based on a time set in accordance with the second control temperature when the first control temperature exceeds a first threshold value.

[0181] (Configuration 11) 8. The lighting device of any one of configurations 1 to 7, wherein when the first control temperature exceeds a first threshold and the second control temperature exceeds a second threshold, the lighting device controls the light-emitting operation based on the second control temperature.

[0182] (Configuration 12) 12. The lighting device according to any one of configurations 1 to 11, wherein the calculation means includes a subtraction process based on the first degree of influence and the second degree of influence, respectively.

[0183] (Configuration 13) 13. The lighting device according to any one of configurations 1 to 12, wherein the second target portion is a member located in the vicinity of the light source.

[0184] (Configuration 14) 13. The lighting device according to any one of configurations 1 to 12, wherein the second target portion is an optical member disposed in front of the light source.

[0185] (Method 1) A method for controlling a lighting device having a first target portion including a light source and a second target portion different from the light source, comprising the steps of: a calculation step of calculating a first control temperature, which is a relative temperature of the first target part, and a second control temperature, which is a relative temperature of the second target part, based on heat generated by a light emission operation of the light source; and a control step of controlling the light emitting operation based on at least one of the first and second control temperatures, A method for controlling a lighting device, characterized in that the calculation step calculates the first control temperature based on a first degree of influence of heat due to the light-emitting operation, and calculates the second control temperature based on a second degree of influence of heat due to the light-emitting operation that is different from the first degree of influence. [Explanation of symbols]

[0186] 100 Strobe Device 100a Main body 100b Light emitting part 101 Strobe Microcomputer 104 Discharge tube 111 Optical Panel 113 Input section 114 Display section 117 Cooling section

Claims

1. a first target portion including a light source; a second target portion different from the light source; a light emission control means for controlling the light emission operation of the light source; a calculation means for calculating a first control temperature, which is the relative temperature of the first target part, and a second control temperature, which is the relative temperature of the second target part, based on heat generated by the light emission operation of the light source; a control means for controlling the light-emitting operation based on at least one of the first and second control temperatures; The lighting device is characterized in that the calculation means calculates the first control temperature based on a first degree of influence of heat due to the light-emitting operation, and calculates the second control temperature based on a second degree of influence of heat due to the light-emitting operation that is different from the first degree of influence.

2. 2. The lighting device according to claim 1, wherein the first influence degree is an influence degree according to at least an amount of light emitted by a light source and a light-emitting time period.

3. 3. The lighting device according to claim 2, wherein the second degree of influence is a degree of influence that depends at least on the amount of light emitted from the light source and the distance from the light source.

4. 2. The lighting device according to claim 1, wherein the light source is a discharge tube.

5. 2. The lighting device according to claim 1, wherein the light source is an LED.

6. 2. The lighting device according to claim 1, wherein the control means controls the light emission based on a time period determined in accordance with the first control temperature and the second control temperature.

7. The lighting device according to claim 1 , wherein the first and second influence levels vary depending on a light-emitting operation mode of the light source.

8. 2. The lighting device according to claim 1, wherein the control means controls the time from when the first light-emitting operation is performed until when the second light-emitting operation is performed.

9. 9. The lighting device according to claim 8, wherein the control means controls the time from when the first control temperature exceeds a first threshold value to when the second light-emitting operation is performed based on a predetermined time.

10. 9. The lighting device according to claim 8, wherein, when the first control temperature exceeds a first threshold, the control means controls the time from when the first light-emitting operation is performed to when the second light-emitting operation is performed based on a time set in accordance with the second control temperature.

11. 2. The lighting device according to claim 1, wherein, when the first control temperature exceeds a first threshold and the second control temperature exceeds a second threshold, the light-emitting operation is controlled based on the second control temperature.

12. 2. The lighting device according to claim 1, wherein the calculation means includes subtraction processing based on the first degree of influence and the second degree of influence.

13. 2. The lighting device according to claim 1, wherein the second target portion is a member located near the light source.

14. 2. The lighting device according to claim 1, wherein the second target portion is an optical member disposed in front of the light source.

15. A method for controlling a lighting device having a first target portion including a light source and a second target portion different from the light source, comprising: a calculation step of calculating a first control temperature, which is the relative temperature of the first target part, and a second control temperature, which is the relative temperature of the second target part, based on heat generated by a light emission operation of the light source; a control step of controlling the light-emitting operation based on at least one of the first and second control temperatures, a control method for a lighting device, wherein the calculation step calculates the first control temperature based on a first degree of influence of heat caused by the light-emitting operation, and calculates the second control temperature based on a second degree of influence of heat caused by the light-emitting operation that is different from the first degree of influence.

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