JP7370798B2 - Lighting device and its control method and program - Google Patents

Description

The present invention relates to a lighting device, a method of controlling the same, and a program, and particularly relates to a lighting device including a cooling unit, a method of controlling the same, and a program.

Conventionally, lighting devices are provided with a cooling unit that limits the temperature rise of an optical panel disposed in front of the lighting device, which occurs when a light emitting unit continuously emits light, to a range where the optical panel can be used safely.

However, the temperature of the light emitting part changes greatly depending on the operating state of the cooling section, so depending on the operating state of the cooling section, it may not be possible to limit the temperature rise of the optical panel, resulting in an issue where the optical panel may not be able to be used safely. was.

In order to solve such a problem, for example, in Patent Document 1, in which a blower section is installed in a lighting device as a cooling section, the amount of air blown by the blower section is adjusted based on the distance between the light emitting section and the optical panel.

Patent No. 6330544

However, the temperature rise curve of the optical panel during continuous light emission is not determined only by the distance between the light emitting unit and the optical panel. For this reason, if the air volume of the air blower is reduced when the distance between the light emitting unit and the optical panel is large as in Patent Document 1, the optical panel will not be able to safely use the temperature rise of the optical panel during continuous light emission. There is a possibility that it will not be possible to limit the amount to what is possible.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a lighting device, a control method thereof, and a program that can appropriately control the temperature rise of an optical panel during continuous light emission.

A lighting device according to claim 1 of the present invention includes a light source, and an optical panel in which a relative position between the light source and the light source is held changeable, and a light distribution angle of light from the light source is changed according to the relative position. a cooling unit that cools the optical panel heated by the light source, the lighting device comprising: a cooling unit that cools the optical panel heated by the light source; a calculation means for calculating a control temperature corresponding to an assumed temperature ; a control means for controlling the operational output of the cooling unit based on the control temperature; a setting/switching means for switching the shortest light emission interval at a set timing; a detection means for detecting whether the cooling unit is in a drivable state or in a non-drivable state; and a setting means for setting calculation parameters used when calculating the control temperature by the calculation means based on the possible number of times and the set timing, and the state detected by the detection means is the driveable state. When the state changes from the state where the drive is disabled to the state where the drive is disabled, the setting/switching means reduces the number of times the light can be emitted and advances the set timing.

According to the present invention, it is possible to appropriately control the temperature rise of the optical panel during continuous light emission.

1 is a block diagram showing a schematic configuration of a strobe device 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 strobe device of FIG. 1. FIG. 3 is a flowchart of light emission processing according to the first embodiment of the present invention in a strobe device. 4 is a flowchart of the state confirmation process in step S302 of FIG. 3. FIG. 4 is a flowchart of continuous light emission control processing in step S311 in FIG. 3. 6 is a flowchart of the state determination process in step S503 of FIG. 5. FIG. 6 is a flowchart of the light emission energy NL calculation process in step S504 of FIG. 5. FIG. 3 is a diagram showing a heat transfer model of the light emitting section in FIG. 2. FIG. 6 is a flowchart of control stage determination processing in step S509 of FIG. 5. FIG. 6 is a flowchart of the zoom position changing process in step S514 of FIG. 5. FIG. 6 is a flowchart of a cooling unit drive control process executed every time the control temperature Tf is calculated in step S508 of FIG. 5. FIG. 3 is a graph showing the actual measured temperature value of the optical panel in FIG. 2 and its assumed panel temperature. FIG. 2 is a block diagram showing a schematic configuration of a strobe device as a lighting device according to a second embodiment of the present invention. It is a flowchart of control parameter determination processing concerning a 2nd embodiment of the present invention. This is a continuation of FIG. 14A.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

(First embodiment)
FIG. 1 is a block diagram showing a schematic configuration of a strobe 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 strobe device 100. Note that the same components in FIGS. 1 and 2 are given the same reference numerals.

First, the configuration of the strobe device 100 will be explained. As shown in FIG. 2, the strobe device 100 includes a main body part 100a that is detachably attached to a camera body (not shown), and a light emitting part that is held rotatably in the vertical and horizontal directions with respect to the main body part 100a. 100b. In addition, in this embodiment, the rotation direction of the light emitting part 100b is defined with the side of the main body part 100a connected to the light emitting part 100b being the upper side.

A microcomputer FPU (hereinafter referred to as a strobe microcomputer) 101 controls each part of the strobe device 100. The strobe microcomputer 101 is, for example, a one-chip IC circuit with a built-in microcomputer that includes a CPU, ROM, RAM, input/output control circuit (I/O control circuit), multiplexer, timer circuit, EEPROM, A/D, D/A converter, etc. The structure is as follows.

The battery 200 functions as a power source (VBAT) for the strobe device 100.

As shown in FIG. 1, the booster circuit block 102 includes a booster section 102a, resistors 102b and 102c used for voltage detection, and a main capacitor 102d. The booster circuit block 102 boosts the voltage of the battery 200 to several hundred volts using the booster 102a to charge the main capacitor 102d with electrical energy for light emission.

The charging voltage of the main capacitor 102d is divided by resistors 102b and 102c, and the divided voltage is input to the A/D conversion terminal MCV_AD of the strobe microcomputer 101.

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 kilovolts applied from the trigger circuit 103, it is excited and emits light using the electrical energy charged in the main capacitor 102d.

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 integrating circuit 107 integrates the light-receiving current of the photodiode 106, and its output is input to the inverting input terminal of the comparator 108 and the A/D converter terminal INT_AD of the strobe microcomputer 101. A non-inverting input terminal of the comparator 108 is connected to a D/A converter terminal INT_DAC in the strobe microcomputer 101, and an output of the comparator 108 is connected to an 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 strobe microcomputer 101, and the output of the AND gate 109 is input to the light emission control circuit 105.

The reflector 110 reflects the light emitted from the discharge tube 104 and guides it in a predetermined direction.

The optical panel 111 is included in a zoom optical system (not shown), and is held so that its relative position (zoom position) with respect to a reflector unit 112 including a discharge tube 104 and a reflector 110 can be changed. In this way, by changing the relative position between the reflector unit 112 and the optical panel 111, the guide number (the light distribution angle of the light from the discharge tube 104) of the strobe device 100 can be changed.

The light emitting section 100b mainly includes a discharge tube 104, a reflector 110, and an optical panel 111, and its irradiation direction changes by rotation from the main body section 100a.

The input unit 113 includes a power switch, a mode setting switch for setting the operating mode of the strobe device 100, including drive settings for the cooling unit 117 (described later), in accordance with user operations, and setting buttons for setting various other parameters in accordance with user operations. including. The strobe microcomputer 101 executes various processes in response to inputs to the input unit 113.

The display unit 114 includes a liquid crystal device and a light emitting element, and displays each status of the strobe device 100.

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

The terminals 116 include a terminal SCLK_S for synchronizing communication between the camera body and the strobe device 100, a terminal MOSI_S for transmitting data from the camera body to the strobe device 100, and a terminal MISO_S for receiving data transmitted from the strobe device 100. . The terminal 116 also includes a GND terminal that connects both the camera body and the strobe device 100.

The cooling unit 117 is a module having a fan for cooling the optical panel 111, and is connected to the terminal FAN_PWM and the terminal FAN_FG of the strobe microcomputer 101. The cooling unit 117 can change the rotation speed of the fan under PWM control from the strobe microcomputer 101 to change the output air volume. Furthermore, by feeding back the rotation speed information to the strobe microcomputer 101, it is possible to maintain the rotation speed as specified by the rotation instruction.

Next, the light emission processing according to this embodiment in the strobe device 100 will be explained using FIG. 3. This process is executed by the CPU included in the strobe microcomputer 101 reading a program held in the ROM also included in the strobe microcomputer 101.

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

In step S301, the strobe microcomputer 101 initializes its own memory and ports. Further, the state of the switch included in the input unit 113 and preset input information are read, and various light emission modes such as how to determine the amount of light emission and the light emission timing are set, and the process moves to step S302.

In step S302, the strobe microcomputer 101 performs a status confirmation process to confirm the status of hardware (hereinafter referred to as target hardware) related to the continuous light emission control process of FIG. 5, which will be described later. Thereafter, the confirmed status result is stored in the RAM of the strobe microcomputer 101, and the process moves to step S303. Details of the status confirmation process will be described later using the flowchart in FIG.

In step S303, the strobe microcomputer 101 causes the booster circuit block 102 to start its operation to charge the main capacitor 102d. After starting charging the main capacitor 102d, the process moves to step S304.

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

In step S305, the strobe microcomputer 101 causes the zoom drive circuit 115 to move the reflector unit 112 so that the distribution angle of the strobe light falls within the range according to the focal length information acquired in step S304, and then in step S306 Move to. Note that if there is no need to move the reflector unit 112, the process directly proceeds to step S306.

In step S306, the strobe microcomputer 101 displays on the display unit 114 an image related to the light emission mode set at the input unit 113 in step S301, an image related to the focal length information acquired in step S304, and the like. Furthermore, if it is detected in the status confirmation process in step S302 that an error condition has occurred in any of the hardware related to the continuous light emission process, a warning is displayed in accordance with the content of the error. After that, the process moves to step S307.

In step S307, the strobe microcomputer 101 checks whether charging of the main capacitor 102d is completed based on the voltage input to the A/D conversion terminal MCV_AD. If charging has been completed, the strobe microcomputer 101 transmits a charging completion signal to the camera microcomputer (not shown) of the camera body via the terminal 116 and proceeds to step S308; if charging has not been completed, the process proceeds to step S302. return.

In step S308, the strobe microcomputer 101 determines whether or not a light emission start signal has been received from the camera microcomputer as a light emission instruction. If so, the process proceeds to step S309; if not, the process returns to step S302.

In step S309, the strobe microcomputer 101 instructs the light emission control circuit 105 to emit light according 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 is completed, information regarding the light emission, such as voltage information of the main capacitor 102d, is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S310. Note that for a series of light emissions such as pre-light emission and main light emission for dimming, the process proceeds to step S310 after the series of light emissions is completed in step S309.

In step S310, it is determined whether the light emission in step S309 is the first light emission, that is, the first light emission after the start of the light emission process in FIG. 3. If it is the first light emission, the process advances to step S311, and if it is the second or subsequent light emission, the process returns to step S302.

In step S311, the strobe microcomputer 101 starts continuous light emission control processing to control light emission and charging to prevent excessive heat generation even if heat continues to be applied due to continuous light emission. Details of the continuous light emission control process will be described later using the flowchart of FIG. This continuous light emission control process repeats the calculations when the control temperature Tf and other calculation results described below are not in the initial state, and ends when the calculation results return to the initial state. That is, the calculation of the assumed temperature of the optical panel 111, which is the target portion to be protected from the influence of heat generated by the light emission in step S309, or a counter that is a substitute for the temperature, is started from the time when the first light emission occurs. Then, the continuous light emission control process of FIG. 5 is continued in parallel with the light emission process of FIG. 3 until the calculation result becomes the same as the initial state, until the time for heat dissipation has elapsed or until a reset is required. Therefore, in this embodiment, the process shown in FIG. 5 is continuous light emission control process, but the same process may be performed for single light emission control. After starting the continuous light emission control process in this way, the process returns to step S302. Furthermore, each time a control temperature Tf, which will be described later, is calculated by the continuous light emission control process, a cooling unit drive control process is executed in order to effectively protect the optical panel 111 from the heat from the discharge tube 104. Details of the cooling unit drive control process will be described later using the flowchart of FIG.

Next, the status confirmation process (step S302) in the strobe device 100 will be explained using the flowchart of FIG.

This process starts when hardware related to the continuous light emission control process (target hardware) is detected. Target hardware refers to components that affect the optical system and heat sources. Specifically, examples include a 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 to the front of the optical panel 111. 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 understand the optical axis of the light emitted from the optical panel 111, and the like.

In step S401, the strobe microcomputer 101 acquires status information of the target hardware. The status information includes information indicating whether each piece of target hardware is mounted on and connected to the strobe device 100, and settings made by the input unit 113 to enable or disable operation. The status information, along with error information described below, is updated every time the status of the target hardware changes. The obtained status information of the target hardware related to the continuous light emission control process is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S402.

In step S402, the strobe microcomputer 101 detects whether the target hardware itself is in an error state based on the status information of the target hardware acquired in step S401. For example, even though the cooling unit 117 is connected to the strobe device 100 and the lighting mode setting performed in step S301 indicates that the cooling unit 117 is operable, the cooling unit 117 may malfunction or otherwise operate. There may be cases where it is not possible. In this case, it is detected that the cooling unit 117 itself, which is the target hardware, is in an error state. As a result of the detection, if the target hardware itself is in an error state, information indicating this is acquired as error information in the RAM included in the strobe microcomputer 101, and the process moves to step S403.

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

Next, continuous light emission control processing (step S311) in the strobe device 100 will be explained using the flowchart of FIG.

This process performs restrictions to protect the light emitting section 100b, particularly the optical panel 111, from the influence of heat generated by the light emission of the discharge tube 104. Specifically, a numerical value that can be used to relatively evaluate the temperature of the optical panel 111 is calculated as the assumed panel temperature, and the light emission interval, charging current, etc. are controlled based on the calculation result.

When the discharge tube 104 emits light for the first time in step S309 in FIG. 3, the strobe microcomputer 101 starts this process in parallel with the light emission process in FIG.

In step S501, the strobe microcomputer 101 initializes settings related to continuous light emission control. The preset input information and parameters are read, and the process moves to step S502. Note that if reading has already been performed in step S301 of FIG. 3, this step can be omitted.

In step S502, the strobe microcomputer 101 starts sampling for controlling continuous light emission. Every time a predetermined sampling time elapses, calculations in steps S503 to S512, which will be described later, are performed. In the following description, calculations within one sampling will be explained, and the calculations are repeated every time a predetermined sampling time elapses until the calculation result becomes the same as the initial state, or until a heat dissipation time elapses or a reset is applied. After starting sampling, the process moves to step S503.

In step S503, the flash microcomputer 101 performs a state determination process to set calculation parameters. Details of the state determination process will be described later using the flowchart of FIG. After setting the calculation parameters in the state determination process, the results are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S504.

In step S504, the strobe microcomputer 101 performs a light emission energy NL calculation process to calculate the light emission energy NL emitted during the main 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, the light emission command information from the camera body, etc. Details of the luminescence energy NL calculation process will be described later using the flowchart of FIG. After calculating the light emission energy NL, it is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S505.

In step S505, the flash microcomputer 101 calculates the 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 the RAM included in the strobe microcomputer 101, and the process moves to step S506.

In step S506, the flash microcomputer 101 calculates the controlled elapsed temperature Tfd. The controlled elapsed temperature Tfd will be described later. After calculating the control elapsed temperature Tfd, the calculation result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S507.

In step S507, the flash microcomputer 101 calculates the 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 the RAM included in the strobe microcomputer 101, and the process moves to step S508.

In step S508, the strobe microcomputer 101 calculates the 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 strobe microcomputer 101, and the process moves to step S509. Note that the cooling unit drive control process (FIG. 11) is executed every time the control temperature Tf is calculated in step S508.

In step S509, the flash microcomputer 101 performs control stage determination processing. The control stage is a stage for setting the shortest light emission interval when continuous light emission is performed in the strobe device 100, and includes a plurality of stages including a warning stage, which is the highest control stage. The shortest light emission interval is set to increase as the control stage increases. Details of the control stage determination process will be described later using the flowchart of FIG. After the control stage determination process, the determination result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S510.

In step S510, the strobe 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 the RAM included in the strobe microcomputer 101, and the process moves to step S511.

In step S511, the strobe microcomputer 101 calculates the 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 the RAM included in the strobe microcomputer 101, and the process moves to step S512.

In step S512, the strobe microcomputer 101 calculates the 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 the RAM included in the strobe microcomputer 101, and the process moves to step S513.

In step S513, the strobe microcomputer 101 compares the zoom position at the time of the last light emission in this sampling with the zoom position at the time of the previous sampling. As a result of the comparison, if there is no change, the process moves to step S515. Incidentally, in the previous sampling, if the zoom position changing process in step S514 is executed and a bit indicating that the zoom position has been changed is set, this bit is lowered. On the other hand, if there is a change as a result of the comparison in step S513, the process moves to step S514.

In step S514, the flash microcomputer 101 performs zoom position change processing. Details of the zoom position changing process will be described later using the flowchart of FIG. After the zoom position change processing, the result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S515.

In step S515, the strobe microcomputer 101 stores various calculation results and the light emission energy -NL in the RAM included in the strobe microcomputer 101, and then proceeds to step S516. If these are already stored in RAM, this step may be omitted.

In step S516, the flash microcomputer 101 checks whether the control temperature Tf and other calculation results have returned to the initial state set in step S501. If it has returned to the initial state, the process moves to step S517, and if it has not returned to the initial state, the process returns to step S503 to start the next sampling.

In step S517, the strobe microcomputer 101 ends the sampling started in step S502, and ends this process.

Next, the state determination process (step S503) will be explained using the flowchart of FIG.

In the state determination process, the state is determined based on the information stored in the state confirmation process of FIG. 4 described above.

In step S601, the flash microcomputer 101 determines whether the cooling unit 117 is included. If the cooling unit 117 is included, the process moves to step S602, and if it does not, the process moves to step S607.

In step S602, the flash microcomputer 101 determines whether the cooling unit 117 is in a drivable state or in a non-drivable state. The drivable state is a state in which the cooling unit 117 is permitted to be driven by the drive setting of the cooling unit 117 by the input unit 113. In addition, the drive-unable state means that driving of the cooling unit 117 is prohibited due to the driving setting of the cooling unit 117 by the input unit 113, or the cooling unit 117 is in an error state in step S402 due to a failure of the cooling unit 117 or the like. This is the state in which it has been detected that there is a If the drive is possible, the process moves to step S603, and if the drive is not possible, the process moves to step S604.

In step S603, the strobe microcomputer 101 determines whether an external power source is detected and whether there is a response from the external power source. This is because continuous charging performance differs depending on the external power source, so the purpose is to optimize the charging performance and protect external power sources that do not support identification responses. As a result of the determination in step S603, if an external power source is detected and there is a response, the process moves to step S605, and if an external power source is detected but there is no response, the INDEX:2 bit is set (step S608a). The process moves to step S609. Further, if an external power source is not detected, the process moves to step S606. Incidentally, the strobe microcomputer 101 sets a possible number of times the discharge tube 104 can emit light from the start of continuous light emission to the warning stage described later, according to the value of INDEX. Further, the strobe microcomputer 101 switches the shortest light emission interval at a timing set according to the value of this INDEX (setting/switching means).

In step S604, the strobe microcomputer 101 determines whether an external power source is attached. Unlike the case of step S603, it is not determined whether there is a response from the external power supply. The reason for this is that the cooling unit 117 is determined to be in a non-driveable state (NO in step S602), and cooling by the cooling unit 117 cannot be used, so it is necessary to set the number of times that light can be emitted to be small in the first place. Therefore, the external power source can be protected by simply lowering the number of times the light can be emitted by a small amount to the extent that it is not necessary to determine whether there is a response from the external power source. Note that if the external power source supports the identification response, the same determination as in step S603 is made. As a result of the determination in step S604, if the external power supply is installed, the INDEX:7 bit is set (step S608f) and the process moves to step S609; if it is not installed, the process moves to step S607.

In steps S605, S606, and S607, the flash microcomputer 101 determines whether an optical accessory is attached. As a result of the determination in step S605, if it is installed, the bit INDEX:4 is set (step S608b). Further, as a result of the determination in step S606, if the device is attached, the bit INDEX:3 is set (step S608d). Similarly, if the result of the determination in step S607 is that the device is attached, the bit INDEX:6 is set (step S608g). After that, the process moves to step S609. On the other hand, if the result of the determination in step S605 is that it is not attached, the bit INDEX:1 is set (step S608c). Furthermore, if the result of the determination in step S606 is that the device is not attached, the bit INDEX:0 is set (step S608e). Similarly, if the result of the determination in step S607 is that the device is not attached, the bit INDEX:5 is set (step S608h). After that, the process moves to step S609.

In step S609, the strobe microcomputer 101 sets the calculation parameter associated with the INDEX whose bit is set. If already set, update the calculation parameters.

In this embodiment, the strobe device 100 is equipped with a cooling unit 117 as shown in FIG. 1, and driving is permitted according to settings from the input unit 113 (YES in step S601, YES in step S602). Furthermore, although an external power source and an optical accessory can be attached to the strobe device 100, the external power source and optical accessory are not attached (no detection in step S603, NO in step S606). Therefore, the strobe microcomputer 101 proceeds to step S608e and sets the INDEX:0 bit. Therefore, in the strobe device 100 of this embodiment, the possible number of times of light emission is set to the energy equivalent to full light emission in step S609. Since the degree of temperature rise of the light emitting unit 100b will also change, the calculation parameter of the conversion gain CS, which will be described later, which affects the switching timing of the shortest light emission interval is also set in step S609. After setting the calculation parameters in step S609, this process ends and the process moves to step S504.

Next, the luminescence energy NL calculation process (step S504) will be explained using the flowchart of FIG. 7.

In this embodiment, the light emission energy NL is calculated from the voltage information of the main capacitor 102d.

In step S701, the strobe microcomputer 101 obtains information on the pre-light emission voltage bVCM from the A/D conversion value of the main capacitor 102d. After obtaining the pre-emission voltage bVCM, the process moves to step S702.

In step S702, the strobe microcomputer 101 obtains information on the post-light emission voltage aVCM from the A/D conversion value of the main capacitor 102d. After acquiring the post-emission voltage aVCM, the process moves to step S703.

In step S703, the strobe microcomputer 101 calculates electrical energy EC using the pre-light emission voltage bVCM obtained in step S701 and the post-light emission voltage aVCM obtained in step S702. Electrical energy EC is determined by the following formula.

According to equation (1), the output range of the electrical energy EC is adjusted by a gain Os, which is an adjustment gain on the firmware, in order to convert it into a number of digits that are easy to control. After calculating the electrical energy EC, the process moves to step S704.

In step S704, the strobe microcomputer 101 calculates the light emission energy NL to be used in an arithmetic expression used in continuous light emission control processing, which will be described later, by weight value conversion. The light emission energy NL is determined by the following approximate formula according to the configuration of the strobe device 100, etc.

Coefficients α and β are adjusted based on measurement data. More specifically, the coefficients α and β are adjusted based on the amount of change in the voltage of the main capacitor 102d for each amount of light emission. After calculating the light emission energy NL, the result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S705.

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

In step S706, the strobe microcomputer 101 adds up the light emission energy NL emitted within the present sampling time, and updates the light emission energy NL. If there is light emission a plurality of times (z) within this sampling time, and if the respective light emission energies calculated in step S704 are NL1, NL2, ..., NLz, the updated light emission energy NL is calculated using the following formula: is required.

In step S309, it is assumed that the pre-emission and the main emission are treated as a series of emission, but in calculating the emission energy NL, the pre-emission is also regarded as an individual emission and is summed using equation (3). Note that if no light is emitted within the sampling time, the value of the light emission energy NL summed up in step S706 becomes 0. After updating the light emission energy NL, the result is stored in the RAM included in the strobe microcomputer 101, the light emission energy NL calculation process is ended, and the process moves to step S505.

Next, various arithmetic expressions (steps S505 to S508 and steps S510 to S512) used in the continuous light emission control process in FIG. 5 will be explained using FIG. 8.

FIG. 8 is a diagram showing a heat transfer model of the light emitting section 100b. FIG. 8(a) is a diagram showing heat radiation to the optical panel 111 when the discharge tube 104 emits light. FIG. 8B is a diagram showing heat transfer from the heated interior space of the light emitting section 100b to the optical panel 111 after the discharge tube 104 emits light. FIG. 8C is a diagram showing heat transfer when heat is radiated from the heated optical panel 111 to the external space after the discharge tube 104 emits light. FIG. 8D is a diagram showing heat transfer when the optical panel 111 heated by the light emitted from the discharge tube 104 radiates 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 section 100b when the discharge tube 104 emits light. FIG. 8(f) is a diagram showing heat transfer when heat is radiated from the heated inner space of the light emitting part 100b to the outer space through the outer shell.

First, as shown in FIG. 8A, the optical panel 111 is heated by heat radiation when the discharge tube 104 emits light. If this amount of heat is defined as the amount of radiant heating Rh, then the following equation is obtained using the above-mentioned luminous energy NL.

Rhc indicates the radiant heating coefficient. Since the effective range of the optical panel 111 and the influence of heat radiation from the discharge tube 104 differ depending on the zoom position, the radiant heating amount Rh is determined by setting the radiant heating coefficient Rhc for each zoom position.

As shown in FIG. 8(b), after the discharge tube 104 emits light, heat transfer from the heated interior space of the light emitting section 100b to the optical panel 111 occurs with a time lag from the time when the aforementioned heat radiation occurs. . If this is the heat transfer heating amount Hh, it is determined by the following formula.

Ci indicates an internal temperature counter, and Cp indicates a panel temperature counter. Further, the prefix pre indicates a result calculated at one or more previous sampling times. Hhc indicates a heat transfer coefficient when heat in the internal space of the light emitting section 100b is transferred to the optical panel 111.

As shown in FIG. 8(c), the optical panel 111 is heated and simultaneously radiates heat. Assuming that the amount of heat radiated from the optical panel 111 to the outside is the panel heat radiation amount Fp, it is determined by the following formula.

T indicates the environmental temperature or a counter serving as an alternative thereof, and Fhc indicates the heat transfer coefficient when heat is radiated from the optical panel 111.

As shown in FIG. 8(d), the optical panel 111 is cooled by air blown by the cooling unit 117. Assuming that the amount of heat forcibly cooling the optical panel 111 by the cooling unit 117 is the amount of forced cooling heat Ap, it is determined by the following formula.

Af is the cooling flow rate, Dt is the operating output, and Afc is the conversion coefficient.

Normally, heat conduction with the outer shell would be included in addition to the above, but this is omitted in this embodiment because the contact area is small and is sufficiently small for heat transfer when the discharge tube 104 emits light.

Next, the internal temperature counter Ci shown by equation (5) is determined.

As shown in FIG. 8E, the internal space of the light emitting section 100b is heated by heat transfer when the discharge tube 104 emits light. When this amount of heat is defined as the amount of heat generated Hv, the following equation is obtained using the light emission energy NL.

Cic indicates an internal temperature coefficient, and is a conversion coefficient from luminous energy NL to calorific value Hv. CS indicates a conversion gain, and has a function of adjusting the deviation in the conversion to the heat generation amount Hv, which changes depending on the temperature of the internal space of the light emitting section 100b.

As shown in FIG. 8(f), the heated internal space of the light emitting section 100b radiates heat. Assuming that the amount of heat radiated to the external space through the outer shell is the internal cooling amount Fi, it is determined by the following formula.

Fic indicates internal cooling coefficient.

The internal temperature counter Ci shown in equation (5) is determined by the following equation.

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

Furthermore, the panel temperature counter Cp shown in equation (5) is obtained by the following equation.

Thereby, the heat transfer heating amount Hh can be determined using equation (5).

と表すことができる。式（１２）より、環境温度Ｔがわかれば、その時の想定パネル温度を求めることができる。本実施形態では公知の温度センサ等を用いず、コストダウンを図りながら連続発光制御を実現することを想定し、また制御の簡単化のため、Ｔ＝０として以降の演算を行う。 Next, the assumed temperature of the optical panel 111 (hereinafter referred to as assumed panel temperature) is calculated using the panel temperature counter Cp obtained by equation (11) and the environmental temperature T. If the assumed panel temperature is Tps,

It can be expressed as. From equation (12), if the environmental temperature T is known, the assumed panel temperature at that time can be determined. 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 control, the subsequent calculations are performed with T=0.

In order to perform calculations related to continuous light emission control processing, formula (12) is expanded and rearranged as follows.

となる。制御温度加算量Ｔｆｕは本サンプリングでの熱放射による光学パネル１１１の発熱を示している。制御経過温度Ｔｆｄは前回のサンプリングの演算結果から想定される本サンプリングでの光学パネル１１１の温度（想定パネル温度）を示している。制御温度減算量Ｔｆａは本サンプリングでの冷却部１１７による光学パネル１１１の冷却熱量を示している。また、制御経過温度Ｔｆｄ内には前回サンプリングのパネル温度カウンタｐｒｅＣｐと前回サンプリングの内部温度カウンタｐｒｅＣｉが含まれるため、図５のフローチャートから、以下の３式で１サンプリング内の演算を完了することができる。 Tf indicates the control temperature, which is the relative temperature of the optical panel 111, and also serves as a light emission counter, which is used for determination of control described later. Here, 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 elapsed temperature Tfd, and the fourth term on the right side is the control temperature subtraction amount Tfa, then

becomes. The control temperature addition amount Tfu indicates the heat generated by the optical panel 111 due to thermal radiation during this sampling. The control elapsed temperature Tfd indicates the temperature of the optical panel 111 in this sampling (assumed panel temperature) assumed from the calculation result of the previous sampling. The control temperature subtraction amount Tfa indicates the amount of heat for cooling the optical panel 111 by the cooling unit 117 in this sampling. Furthermore, since the control elapsed temperature Tfd includes the panel temperature counter preCp of the previous sampling and the internal temperature counter preCi of the previous sampling, from the flowchart in FIG. 5, it is possible to complete the calculation within one sampling using the following three equations. can.

The above is the calculation formula used in the continuous light emission control process. That is, in step S505, the first equation of equation (14), in step S506, the second equation of equation (14), in step S507, the third equation of equation (14), and in step S508, the fourth equation of equation (14). Calculations are performed using the eyes. Further, calculations are performed using equation (15) in step S510, equation (16) in step S511, and equation (17) in step S512. Further, in equations (15) to (17), the panel temperature counter, internal temperature counter, and internal cooling heat amount are respectively calculated to be fed back to the next sampling. This makes it possible to calculate the expected panel temperature based on the heat dissipation time, the air flow rate determined by the operating output Dt of the cooling unit 117 and the corresponding cooling flow rate Af, and the temperature difference in the internal space of the optical panel 111 and the light emitting unit 100b. Become.

Next, the control stage determination process (step S509) during the continuous light emission control process will be explained using the flowchart of FIG.

In step S901, the strobe microcomputer 101 acquires the zoom position at the time of light emission in the main sampling from the zoom detection unit 115a, stores the result in the RAM included in the strobe microcomputer 101, and then proceeds to step S902.

In step S902, the strobe microcomputer 101 reads a plurality of determination threshold values set corresponding to the zoom position acquired in step S901 from the RAM included in the strobe microcomputer 101, and proceeds to step S903. Here, the plurality of determination threshold values each indicate the lowest temperature of a different control stage.

In step S903, the flash microcomputer 101 determines the control stage based on the control temperature Tf determined in step S508 and the determination threshold read in step S902. Specifically, the control temperature Tf is compared in order from the highest control stage to see whether it exceeds the determination threshold, and as a result of the comparison, when the control temperature Tf exceeds the determination threshold, the determination threshold is set to the lowest temperature. It is determined that this is the control stage. Thereafter, the determined control stage is stored in the RAM included in the strobe microcomputer 101, and then the process moves to step S904.

In step S904, the strobe microcomputer 101 updates the current control stage to the control stage determined in step S903, and updates related parameters. By updating the control stage, the shortest emission interval is changed. This step may be omitted if there is no change from the current control stage. After updating the control stage, the result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S905.

In step S905, the flash microcomputer 101 determines whether the control stage updated in step S904 is in the warning stage. If the control stage is not updated in step S904 and the step is omitted, this step may be omitted. If it is in the warning stage, the process moves to step S906, and if it is not in the warning stage, the control stage determination process in FIG. 9 is ended and the process moves to step S510. Note that if the sampling time is not in the warning stage and the sampling time has been updated to the determination processing time for the warning stage, which will be described later, in step S906, the sampling time is returned to the sampling time set in step S502.

In step S906, the strobe microcomputer 101 updates the sampling time set in step S502 to the judgment processing time for the warning stage. Here, the determination processing time is a time longer than the sampling time set in step S502. This is because when the warning display in the next step S907 is updated at the sampling time set in step S502, a phenomenon such as chattering occurs on the display, which not only makes the display difficult to see, but also prevents the user from using the strobe device 100. This is because it may be mistaken for a malfunction. After applying the judgment processing time for the warning stage, the result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S907.

In step S907, the strobe microcomputer 101 (display control means) causes the display unit 114 to display a warning for the corresponding warning stage, and then ends the control stage determination process and proceeds to step S510.

Next, the zoom position changing process (step S514) during the continuous light emission control process will be explained using the flowchart of FIG.

In step S1001, the flash microcomputer 101 reads the determination threshold value of the control temperature Tf of the control stage determined in step S509 at the zoom position before the zoom position is changed. After reading the determination threshold before change, the process moves to step S1002.

In step S1002, the flash microcomputer 101 reads the determination threshold value of the control temperature Tf of the control stage determined in step S509 at the zoom position after the zoom position has been changed. After reading the changed determination threshold, the process moves to step S1003.

In step S1003, the flash microcomputer 101 performs a conversion process on the panel temperature counter preCp, which is the calculation result of step S510, using the ratio of the determination threshold values read in each of steps S1001 and S1002. This is because the range of control steps differs at each zoom position. The value of the panel temperature counter Cp after conversion is determined by the following equation from equation (15), where the judgment threshold before conversion is FPZ and the judgment threshold after conversion is FAZ.

After the conversion process in step S1003, the calculation result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1004.

In step S1004, similarly to step S1003, the strobe microcomputer 101 performs a conversion process on the internal temperature counter preCi, which is the calculation result of step S511, using the ratio of the determination threshold values read in each of steps S1001 and S1002.

After the conversion process in step S1004, the calculation result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1005.

In step S1005, the strobe microcomputer 101 updates the pre-change determination threshold with the changed determination threshold, and stores it in the RAM included in the strobe microcomputer 101. This allows the current determination threshold to be used as the pre-change determination threshold in the next sampling. It also sets a bit indicating that the zoom position has been changed. If this bit is set, the control stage determination process in step S509 is not performed. This is because feedback is performed in the 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 internal temperature counter Ci calculated at the previous zoom position. This is because if control stage determination is performed at that stage, the control stage may temporarily deviate from the normal value. After storing the bits in the RAM included in the strobe microcomputer 101, the zoom position changing process shown in FIG. 10 is ended.

Next, the cooling unit drive control process that starts in conjunction with the continuous light emission control process in FIG. 5 will be described using the flowchart in FIG. 11.

The cooling unit drive control process is a process of cooling the optical panel 111 by blowing air from the cooling unit 117 in order to protect the light emitting unit 100b, especially the optical panel 111, from the effects of heat generated by the light emission of the discharge tubes 104. . By determining the operating output Dt during air blowing based on the control temperature Tf, the operating output Dt is increased to increase cooling efficiency when the temperature of the optical panel 111 is high, and the operating output is increased when the temperature of the optical panel 111 is low. This enables control to reduce drive noise and power consumption by lowering Dt.

When the control temperature Tf is calculated in step S508 in FIG. 5, the strobe microcomputer 101 starts the cooling unit drive control process shown in FIG.

In step S1101, the strobe microcomputer 101 reads the result of the control temperature Tf calculated in step S508 from the RAM. After reading the control temperature Tf, the process moves to step S1102.

In step S1102, the strobe microcomputer 101 reads a plurality of cooling unit drive control threshold values that determine the operating output Dt of the cooling unit 117 from the RAM included in the strobe microcomputer 101, and proceeds to step S1103.

In step S1103, the strobe microcomputer 101 determines which control stage (cooling control stage) the control temperature Tf read in step S1101 is among the plurality of cooling unit drive control thresholds read in step S1102. Then, the operational output Dt corresponding to the determined control stage is determined. Specifically, information indicating the value of the operational output Dt for each control stage is stored in advance in the ROM of the flash microcomputer 101, and this information is used to make this determination. After determining the operational output Dt, the result of the operational output Dt is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1104.

In step S1104, the strobe microcomputer 101 updates the drive control settings in order to drive the cooling unit 117 with the operating output Dt determined in step S1103. After updating the drive control settings, the setting results are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1105.

In step S1105, the flash microcomputer 101 checks whether the cooling unit 117 is being driven at the operating output set in step S1104 and whether there is any abnormality in the operating output. If there is no abnormality in the operational output, the process ends the cooling unit drive control process in FIG. 11 and returns to step S302, and if there is an abnormality in the operational output, the process moves to step S1106.

In step S1106, the strobe microcomputer 101 determines that the cooling unit 117 cannot operate normally due to a failure or the like, and stops driving the cooling unit 117. Then, the state determination process in step S503 is executed to update the INDEX that sets the bit, and to update the settings for the calculation parameters linked to the INDEX. In the example of this embodiment, the bit set from INDEX:0 to INDEX:5 is updated, and the setting is updated to the calculation parameter linked to INDEX:5. After updating the calculation parameter settings, the cooling unit drive control process of FIG. 11 is ended.

Note that in step S1103, the operating output Dt of the cooling unit 117 may be determined based on the determination threshold used in the control stage determination process in step S902 instead of the cooling unit drive control threshold in step S1102. Although this makes it difficult to finely adjust the operating output Dt, it is possible to eliminate the need for a table of cooling unit drive control threshold values, and to link the shortest light emission interval and the operating output Dt for each control stage.

Next, an example in which the optical panel 111 can be effectively protected by the light emission process of FIG. 3 described above will be described using the graph of FIG. 12.

FIG. 12 is a graph showing the measured temperature value of the optical panel 111 and its assumed panel temperature. As mentioned above, the assumed panel temperature can be determined using equation (12).

The temperature results of the optical panel 111 are shown when the drive of the cooling unit 117 is stopped from the input unit 113 150 seconds after the end of continuous light emission with the cooling unit 117 being driven.

In the example of FIG. 12, the temperature of the optical panel 111 rises to around 88°C due to continuous light emission, and then the temperature is temporarily lowered to around 72°C before the driving of the cooling unit 117 stops, based on the actual measurement value indicated by the dotted line. . However, after the cooling unit 117 is stopped, the temperature rises again to around 100° C. due to the heat in the internal space of the light emitting unit 100b heated by the discharge tube 104. The assumed panel temperature Tps of Equation (12) shown by the solid line is calculated by assuming the temperature change of the optical panel 111 caused by the cooling unit 117 stopping from being driven by the series of processes and calculations described above. is possible. In the example of FIG. 12, when the cooling unit 117 changes from the driving state to the stopped state, the calculation parameters are updated from INDEX:0 to INDEX:5 according to the state determination process (FIG. 6) in step S503. This reduces the number of times that light can be emitted and also advances the timing of switching the shortest light emitting interval. By doing so, even if the cooling unit 117 continues to emit light while it is in a stopped state, the optical panel 111 can be protected from the heat of the discharge tube 104 by controlling the light emission based on the control temperature Tf determined from the assumed panel temperature Tps. can be protected. Similarly, when the cooling unit 117 changes from the stopped state to the driven state, the calculation parameters are updated from INDEX:5 to INDEX:0 according to the determination flow in the state determination process in step S503. As a result, the number of times that light can be emitted is increased within an appropriate range, and the switching timing of the shortest light emitting interval is delayed.

As described above, various processes associated with light emission by the strobe device 100 are executed. In this embodiment, the strobe microcomputer 101 has been described as having a one-chip IC circuit configuration with a built-in microcomputer that includes a CPU that executes the series of processes described above, a RAM that stores various information, etc., but is not limited to this. For example, a dedicated control unit, determination unit, memory, etc. may be provided to execute each of the series of processes described above. Further, although the cooling unit 117 has been described as a fan module, it may be a cooling module having an equivalent function such as a pump.

Note that each flowchart described in this embodiment is just an example, and various processes may be executed in a different order from each flowchart described in this embodiment if there is no inconvenience.

(Second embodiment)
A second embodiment of the present invention will be described below with reference to FIGS. 13, 14A, and 14B.

Among the configurations of the strobe device 150 as the illumination device of this embodiment, the same components as those of the strobe device 100 according to the first embodiment are given the same reference numerals, and redundant explanation will be omitted.

In this embodiment, the light emitting unit 100b further includes a modeling LED 118, and the cooling unit 117 is also driven when protecting the optical panel 111 from the heat generated by the modeling LD 118. Therefore, for example, the second embodiment differs from the first embodiment in that the setting condition for the operating output Dt of the cooling unit 117 exists other than the control temperature Tf calculated based on the heat transfer model of FIG. 8. That is, the strobe device 150 includes a light emitting section thermometer 119 and a control section thermometer 120, and information on the temperature detected by these can also be used as a setting condition for the operating output Dt of the cooling section 117. . In this way, the present embodiment has a plurality of setting conditions for various control parameters including the operating output Dt of the cooling unit 117.

In this way, the present embodiment actually sets various control parameters in the strobe device 150 using setting conditions that allow the set control parameters to reliably protect the optical panel 111 among the plurality of setting conditions. The feature is that it can be set.

FIG. 13 is a block diagram showing a schematic configuration of a strobe device 150 as a lighting device according to a second embodiment of the present invention.

The modeling LED 118 is a light projection LED used to aim the optical axis direction of the light emitted from the discharge tube 104 from the optical panel 111 before the discharge tube 104 emits light. The modeling LED 118 is unitized with a dedicated small lens (not shown), and is arranged in the light emitting section 100b at a position having an optical axis approximately equal to the optical axis of the optical panel 111. In addition, the modeling LED 118 is also equipped with an LED heat dissipation section (not shown) that suppresses the heat generated when it is lit, and a portion of the air blown from the cooling section 117 hits the LED heat dissipation section, further increasing the heat dissipation effect. There is.

The light emitting section thermometer 119 is connected to the strobe microcomputer 101 and is placed in the light emitting section 100b at a position where it does not block the optical path of the light from the discharge tube 104. The light emitting section thermometer 119 detects the temperature of the light emitting section 100b, which increases in temperature due to light emission from the discharge tube 104. Information on the temperature detected by the light emitting section thermometer 119 is transmitted to the strobe microcomputer 101 and stored in the RAM included in the strobe microcomputer 101.

The control section thermometer 120 is connected to the strobe microcomputer 101 and is located within the main body section 100a at a position where the influence of heat radiation from the light emitting section 100b heated by the discharge tube 104 is small. That is, the control section thermometer 120 detects the temperature inside the main body section 100a of the strobe device 150. Information on the temperature detected by the control section thermometer 120 is transmitted to the strobe microcomputer 101 and stored in the RAM included in the strobe microcomputer 101.

Next, control parameter determination processing according to this embodiment in the strobe device 150 will be described using FIGS. 14A and 14B.

In the first embodiment, the shortest light emission interval (hereinafter referred to as shortest light emission interval Ft) is set from the control stage determined by the control stage determination process (FIG. 9). Furthermore, the value of the operating output Dt of the cooling unit 117 is determined in the cooling unit drive control process (FIG. 11) from the control temperature Tf calculated in the continuous light emission control process (FIG. 11).

In contrast, in the control parameter determination process according to the present embodiment, various control parameters (possible number of times of light emission, shortest light emission interval, operational output of the cooling unit 117) under a plurality of setting conditions are first determined. Thereafter, the values of various control parameters under the plurality of setting conditions obtained are compared, and the control parameter that provides the greatest protection effect for the optical panel 111 is actually used in the strobe device 150. In this embodiment, the cooling unit 117 is set to the operating output DtL under the setting condition that the modeling LED 118 is lit. Furthermore, when the temperature of the light emitting section 100b heated by the light emission of the discharge tube 104 or the lighting of the modeling LED 118 is detected by the light emitting section thermometer 119 as a setting condition, the cooling section 117 is set to the operating output DtT and at the same time , is set to the shortest light emission interval FtT.

In step S1401, the flash microcomputer 101 checks whether the power switch of the input unit 113 is turned on. If the power switch of the input unit 113 is turned on, the process moves to step S1402, and if it is turned off, the process moves to step S1414.

In step S1402, the flash microcomputer 101 determines whether the cooling unit 117 is in a drivable state or in a non-drivable state. This determination is the same as step S602 in FIG. 6, so the details will be omitted. If the drive is possible, the process moves to step S1403, and if the drive is not possible, the process moves to step S1414.

In step S1403, the strobe microcomputer 101 checks whether the strobe device 150 is in an auto power-off state. If it is in the auto power off state, the process moves to step S1414, and if it is not in the auto power off state, the process moves to step S1404.

In step S1404, the strobe microcomputer 101 detects the temperature with the light emitting part thermometer 119, and sets the operating output of the cooling part 117 and the shortest light emission when the detected temperature information (hereinafter referred to as temperature control conditions) is set as the setting condition. Calculate the interval. In this embodiment, based on the temperature information detected by the light emitting part thermometer 119, it is determined in which temperature control stage the temperature of the light emitting part 100b is among a plurality of temperature control thresholds, and the process corresponds to the determined temperature control stage. The operating output DtT and the shortest light emission interval FtT are determined. In this embodiment, information indicating the value of the operating output DtT and the value of the shortest light emission interval FtT for each temperature control stage is stored in advance in the ROM of the strobe microcomputer 101, and this information is used to make this determination. Further, it is preferable to provide temperature control stages in stages at intervals similar to the control stages between the cooling unit drive control threshold values shown in the first embodiment, since it facilitates comparisons to be described later. Thereafter, the determined shortest light emission interval FtT and operating output DtT in the temperature control stage are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1405.

In step S1405, the strobe microcomputer 101 sets the shortest light emission interval FtT and the operating output DtT of the cooling unit 117 as control parameters in the tentative selection state based on the result determined in step S1404. Note that, instead of the shortest light emission interval FtT and the operating output DtT of the cooling unit 117, the determined temperature control stage may be set as the control parameter in the temporarily selected state. Thereafter, the set control parameters in the temporarily selected state are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1406.

In step S1406, the strobe microcomputer 101 calculates the control temperature Tf by performing the same process as the continuous light emission control process (FIG. 5) shown in the first embodiment, and the calculated control temperature Tf is 0 (zero). ). If the control temperature Tf exceeds 0 (zero), information on the control temperature Tf (hereinafter referred to as continuous light emission control condition) is provisionally determined as a setting condition and the process moves to step S1407; if it is 0 (zero), step S1409 Move to. In addition, since the control temperature Tf is defined as 0 (zero) or more, it does not become negative.

In step S1407, the strobe microcomputer 101 determines which control stage (cooling control stage) the control temperature Tf is at between a plurality of cooling unit drive control thresholds, similarly to the cooling unit drive control process in the first embodiment (FIG. 11). Determine if there are any. Then, the operational output Dt corresponding to the determined control stage is determined. Furthermore, the shortest light emission interval Ft is determined based on the control stage determined in the control stage determination process of FIG. After that, the shortest light emission interval Ft and the operation output Dt are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1408.

In step S1408, the strobe microcomputer 101 sets the shortest light emission interval Ft and the operating output Dt of the cooling unit 117 as control parameters in the tentative selection state based on the result determined in step S1407. Note that, instead of the shortest light emission interval Ft and the operating output Dt of the cooling unit 117, the determined control stage may be set to the provisional selection state. Thereafter, the set control parameters in the temporarily selected state are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1409.

In step S1409, the strobe microcomputer 101 checks whether the modeling LED 118 is on or off. If it is lit, information that the modeling LED 118 is lit (hereinafter referred to as modeling LED condition) is provisionally determined as a setting condition and the process moves to step S1410, and if it is turned off, the process moves to step S1411.

In step S1410, the strobe microcomputer 101 sets the operating output DtL of the cooling unit 117 under the modeling LED condition as a control parameter in the temporarily selected state. Thereafter, the set control parameters in the temporarily selected state are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1411. Note that instead of the operating output DtT of the cooling unit 117, the lowest temperature control stage may be set as the provisional selection state.

In step S1411, the strobe microcomputer 101 determines a control parameter that maximizes the shortest light emission interval and the maximum operational output of the cooling unit 117 from the control parameters provisionally selected in steps S1405, S1408, and S1410. That is, the values of the shortest light emission interval FtT and the shortest light emission interval Ft are compared, and the larger value (ie, the shortest light emission interval is longer) is determined as the control parameter to be actually set in the strobe device 150. Regarding the cooling unit 117, the values of the operating output DtT, the operating output Dt, and the operating output DtL are compared, and the largest value (that is, the maximum airflow amount) is determined as the control parameter to be actually set in the strobe device 150. .

Note that if a temperature control stage or a control stage is set in the control parameters in the provisionally selected state, it is first determined in step S1408 which temperature control stage the set control stage corresponds to. Thereafter, the highest temperature control stage among the determined temperature control stage and the temperature control stages set in steps S1405 and S1410 is determined as the control parameter to be actually set in the strobe device 150.

By doing so, the control parameters can be determined in consideration of the three setting conditions: temperature control conditions, continuous light emission control conditions, and LED modeling conditions. Therefore, even when the number of heat sources such as the modeling LED 118 increases, the optical panel 111 can be protected more reliably. Thereafter, the determined control parameters are stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1412. Note that the shortest light emission interval set in the strobe device 150 is updated at the time when the control parameters are determined in step S1411, and is applied from the timing of subsequent light emission instructions.

In step S1412, the strobe microcomputer 101 determines whether the operating output of the cooling unit 117 determined as a control parameter in step S1411 exceeds 0 (zero). If the operating output of the cooling unit 117 exceeds 0 (zero), the process moves to step S1413, and if it is 0 (zero), the process moves to step S1414. In addition, since the operating output is defined as 0 (zero) or more, it does not become negative (reverse air blowing).

In step S1413, the strobe microcomputer 101 updates the operating output of the cooling unit 117 set in the strobe device 150 to the operating output of the cooling unit 117 determined as the control parameter in step S1411, and starts driving. After starting the drive, the process moves to step S1415.

In step S1414, the strobe microcomputer 101 stops driving the cooling unit 117. If it has already stopped, this step may be omitted. After the drive is stopped, the process moves to step S1415.

In step S1415, the strobe microcomputer 101 feeds back the operating output of the cooling unit 117 and determines whether it is being driven with the operating output as set. After the determination, the determination result is stored in the RAM included in the strobe microcomputer 101, and the process moves to step S1416.

In step S1416, the flash microcomputer 101 determines whether there is an error in the operational output of the cooling unit 117 due to malfunction such as a failure, based on the determination result in step S1415. If it is determined that there is an error, the process moves to step S1417, and if it is determined that there is no error, the process returns to step S1401.

In step S1417, the flash microcomputer 101 displays a warning on the display unit 114 to the effect that the cooling unit 117 is malfunctioning. After displaying the warning, the process moves to step S1414, and the driving of the cooling unit 117 is stopped. If it has already stopped, this step may be omitted. After the drive is stopped, the process moves to step S1415.

As described above, according to the control parameter determination process shown in FIG. 14A and FIG. Tentatively select control parameters. Thereafter, among the temporarily selected control parameters, the maximum shortest light emission interval and the operating output of the cooling unit are determined as control parameters. Thereby, the optical panel 111, which is heated by the light emitted from the discharge tube 104, can be reliably protected.

Further, the possible number of times of light emission under the above three setting conditions may also be determined in the same manner as the other control parameters, and may be set in a provisional selection state. In this case, the smallest possible number of times of light emission among the temporarily selected possible times of light emission under each setting condition is determined as the control parameter. Thereby, the optical panel 111, which is heated by the light emitted from the discharge tube 104, can be reliably protected.

Note that in the flowcharts of FIGS. 14A and 14B, information on the temperature detected by the light emitting section thermometer 119 is used only when tentatively determining the temperature control conditions in step S1404; It may also be used to calculate Tf.

Regarding an example in which information on the temperature detected by the light emitting part thermometer 119 is used to calculate the control temperature Tf, differences will be explained using the flowchart of FIG. 5.

In step S511, the strobe microcomputer 101 calculates the internal temperature counter Ci based on the temperature information detected by the light emitting section thermometer 119. Assuming that the temperature Ti is detected by the light emitting section thermometer 119, the internal temperature counter Ci can be converted using the following formula.

The coefficients σ and τ vary depending on the configuration of the strobe device 150, and are adjusted based on measurement data.

Further, by using equation (12) and the temperature detected by the control section thermometer 120 as a substitute for the environmental temperature T, it is possible to obtain the assumed panel temperature Tps. As a result, in the first embodiment, the control temperature Tf was calculated with T=0 to simplify the control, whereas in the present embodiment, the control temperature Tf can be calculated corrected by the environmental temperature T. becomes.

Regarding other points, continuous light emission control processing is performed in the same manner as in the first embodiment, and the control temperature Tf is calculated in step S1406.

As described above, in this embodiment, the strobe device 150 has a plurality of setting conditions for various control parameters (the number of possible flashes, the shortest flash interval, the operating output of the cooling unit 117), and one of the setting conditions is used. The set control parameters are set in the strobe device 150.

Note that each flowchart described in this embodiment is just an example, and various processes may be executed in a different order from each flowchart described in this embodiment if there is no inconvenience.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the invention.

[Other embodiments]
It goes without saying that the object of the present invention can also be achieved by supplying the device with a storage medium recording software program codes that implement the functions of the embodiments described above. At this time, the computer (or CPU or MPU) including the control unit of the supplied device reads and executes the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the embodiments described above, and the program code itself and the storage medium storing the program code constitute the present invention.

As the storage medium for supplying the program code, for example, a flexible disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, nonvolatile memory card, ROM, etc. can be used.

Further, based on the instructions of the program code described above, the OS (basic system or operating system) running on the device performs part or all of the processing, and the functions of the embodiment described above are realized by the processing. Needless to say, this also includes cases.

Furthermore, the functions of the embodiments described above may be realized by writing the program code read from the storage medium into a memory provided in a function expansion board inserted into the device or a function expansion unit connected to a computer. Needless to say, it is included. At this time, a CPU or the like provided in the function expansion board or function expansion unit performs part or all of the actual processing based on instructions from the program code.

100 Strobe device 100a Main unit 100b Light emitting unit 101 Strobe microcomputer 104 Discharge tube 111 Optical panel 113 Input unit 114 Display unit 117 Cooling unit 118 Modeling LED
119 Light-emitting part thermometer

Claims (10)

a light source; an optical panel in which a relative position between the light source and the light source is changeable; and a light distribution angle of light from the light source is changed according to the relative position; and an optical panel heated by the light source; A lighting device comprising a cooling unit,
Calculating means for calculating a control temperature corresponding to the temperature assumed in the optical panel based on the relative position, the light emission of the light source, and the heat transfer caused by driving the cooling unit;
A control means for controlling the operating output of the cooling unit based on the control temperature ;
Setting/switching means for setting the number of times the light source can emit light during continuous light emission and switching the shortest light emission interval at a set timing;
a detection means for detecting whether the cooling unit is in a drivable state or in a non-drivable state;
Setting means for setting calculation parameters used when calculating the control temperature by the calculation means based on the possible number of times of light emission and the set timing,
When the state detected by the detection means changes from the drivable state to the non-drivable state, the setting/switching means reduces the number of times the light can be emitted and advances the set timing. A lighting device featuring: When the state detected by the detection means changes from the non-driveable state to the driveable state, the switching means increases the number of times the light can be emitted and also delays the set timing. The lighting device according to claim 1, characterized in that: The device further includes a drive setting unit configured to set the drive of the cooling unit in response to a user operation from an input unit, and the detection unit determines whether the cooling unit is in the driveable state based on the drive setting of the cooling unit. The lighting device according to claim 1 or 2 , wherein the lighting device detects whether the drive is disabled. Further comprising updating means for updating, at a first sampling time, a control step that determines the shortest light emission interval from among the plurality of control steps according to the relative position,
The possible number of times the light source can emit light is the number of times the light source can emit light from the start of the continuous light emission until a warning step that increases the shortest light emission interval among the plurality of control steps. Item 3. The lighting device according to any one of Items 1 to 3 . 5. The lighting device according to claim 4, further comprising display control means for causing a display unit to display a warning when the warning stage is reached. 6. The lighting device according to claim 4 , wherein when the lighting device is in the warning stage, the updating means performs updating at a sampling time interval longer than the first sampling time. 7. The lighting device according to claim 4 , wherein the calculation means calculates the control temperature at the first sampling time. The at least one control parameter has a plurality of setting conditions for changing at least one control parameter of the possible number of times of light emission, the shortest light emission interval, and the operating output of the cooling unit, and the at least one control parameter in at least one of the plurality of setting conditions. further comprising provisional selection means for provisionally selecting the
8. Any one of claims 1 to 7 , wherein among the temporarily selected control parameters, the smallest number of possible light emission, the maximum shortest light emission interval, and the maximum operating output of the cooling unit are determined as the control parameters. 2. The lighting device according to item 1. a light source; an optical panel in which a relative position between the light source and the light source is changeable; and a light distribution angle of light from the light source is changed according to the relative position; and an optical panel heated by the light source; A method of controlling a lighting device comprising a cooling unit,
a calculation step of calculating a control temperature corresponding to the temperature assumed in the optical panel based on the relative position, the light emission of the light source, and the heat transfer caused by driving the cooling unit;
a setting/switching step of setting the number of times the light source can emit light during continuous light emission and switching the shortest light emission interval at a set timing;
a detection step of detecting whether the cooling unit is in a drivable state or in a non-drivable state;
a setting step of setting calculation parameters used when calculating the control temperature in the calculation step, based on the possible number of times of light emission and the set timing;
a control step of controlling the operating output of the cooling unit based on the control temperature ,
When the state detected in the detection step changes from the drivable state to the non-drivable state, in the setting/switching step, the number of times the light can be emitted is decreased and the set timing is advanced. A control method characterized by: A program for executing the control method according to claim 9 .

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