JP2017156571A - Illumination device, control method thereof, control program, and imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illumination device capable of controlling to achieve satisfactory light emission while preventing temperature rise on the illumination device.SOLUTION: A stroboscope 300 has a light emission part 300b that radiates a subject with light when picking up an image of a subject with a camera. A stroboscope microcomputer 310 calculates the light emission energy when the light emission part emits light and calculates temperature rise due to light emission by the light emission part. The stroboscope microcomputer controls the light emission by the light emission part on the basis of the light emission energy and the temperature rise.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lighting device, a control method thereof, a control program, and an imaging device, and more particularly to a lighting device capable of controlling heat generation due to light emission.

  In general, lighting devices such as strobe devices used in imaging devices such as digital cameras are limited to light emission in order to prevent the temperature of the lighting device from rising due to heat generated by light emission and causing discomfort to the user. Yes. On the other hand, if the light emission is restricted, the timing at which the illumination apparatus can emit light is restricted, such as the fact that light cannot be emitted suddenly during photographing.

  In order to cope with such a problem, there is a light emission counter that adds a count value according to a light emission condition, and restricts light emission when the count value of the light emission counter reaches a predetermined count value (Patent Literature). 1).

JP 2008-185699 A

  However, in the lighting device described in Patent Document 1, since subtraction is not performed until the time during which light emission is not performed reaches a predetermined time, if light emission continues for a little shorter time than the predetermined time, the light emission counter No subtraction is performed at. As a result, light emission is limited in a state where the lighting device does not generate much heat, and the timing at which the lighting device can emit light is likely to be limited.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an illuminating device, a control method thereof, a control program, and an imaging device that can perform good light emission control while suppressing temperature rise of the illuminating device.

  In order to achieve the above object, a lighting device according to the present invention includes a light emitting means, a first calculating means for obtaining light emission energy when light is emitted from the light emitting means, and a second for obtaining a temperature rise due to light emission of the light emitting means. And calculating means for controlling light emission by the light emitting means based on the emission energy and the temperature rise.

  ADVANTAGE OF THE INVENTION According to this invention, favorable light emission control can be performed, suppressing the temperature rise of an illuminating device.

It is a figure which shows the structure about an example of an imaging device provided with the illuminating device by the 1st Embodiment of this invention. It is a figure which fractures | ruptures a part about the imaging device shown in FIG. 1, and shows the structure. 2 is a flowchart for explaining light emission processing of the strobe shown in FIG. 1. It is a flowchart for demonstrating the continuous light emission control shown in FIG. 6 is a flowchart for explaining an example of a control stage determination process shown in FIG. It is a figure for demonstrating an example of the heat transfer model in the optical panel shown in FIG. 1, (a) is a figure which shows the thermal radiation with respect to the optical panel when a discharge tube light-emits, (b) is a discharge tube light-emission. The figure which shows the heat transfer with respect to an optical panel from the internal space of a subsequent light emission part, (c) is a figure which shows the heat transfer from the optical panel after a discharge tube light-emits to external space. It is a figure for demonstrating the heat transfer model by the light emission of the interior space in the light emission part shown in FIG. 1, (a) is a figure which shows the heat transfer with respect to the interior space of the light emission part at the time of discharge tube light emission, (b) ) Is a diagram showing heat transfer when heat is radiated from the internal space of the light emitting unit to the external space through the outer shell. It is a figure which shows the calculation result obtained using the optical panel temperature actual value and Formula (13), and its temperature difference. 5 is a flowchart for explaining zoom position change processing shown in FIG. 4. It is a block diagram which shows the structure about an example of the camera provided with the strobe by the 2nd Embodiment of this invention. It is a flowchart for demonstrating the continuous light emission control performed with the strobe shown in FIG. It is a figure which shows an example of the operation | movement in the warning stage for preventing the chattering on a display in the strobe shown in FIG. It is a figure which shows the structure about an example of the camera provided with the flash by the 3rd Embodiment of this invention.

  Below, an example of the illuminating device by embodiment of this invention is demonstrated with reference to drawings.

[First Embodiment]
FIG. 1 is a diagram illustrating a configuration of an example of an imaging device including the illumination device according to the first embodiment of the present invention. FIG. 2 is a diagram illustrating a configuration of the imaging apparatus illustrated in FIG.

  With reference to FIGS. 1 and 2, the illustrated imaging apparatus is, for example, a digital camera (hereinafter simply referred to as a camera), and the camera has a camera body 100. An interchangeable photographic lens unit (hereinafter simply referred to as a photographic lens: imaging optical system) 200 is attached to the camera body 100. Furthermore, a light emitting device (illumination device) such as a detachable strobe device 300 is attached to the camera body 100.

  The camera body 100 is provided with a microcomputer (CCPU: hereinafter referred to as camera microcomputer) 101, and the camera microcomputer 101 controls the entire camera. The camera microcomputer 101 is a one-chip IC circuit with a built-in microcomputer. The camera microcomputer 101 includes a CPU, ROM, RAM, input / output control circuit (I / O control circuit), multiplexer, timer circuit, EEPROM, A / D converter, D / A converter, and the like. Then, the camera microcomputer 101 controls the camera body 100, the photographing lens 200, and the strobe 300 according to a program (that is, software) and performs various condition determinations.

  The image sensor 102 is a CCD or CMOS sensor including an infrared cut filter and a low-pass filter. An optical image (subject image) is formed on the image sensor 102 via a lens group 202 described later, and the image sensor 102 outputs an electrical signal (analog signal) corresponding to the optical image.

  The shutter 103 shields the image sensor 102 when not photographing, and opens a shutter curtain when photographing to guide an optical image to the image sensor 102. The main mirror (half mirror) 104 reflects light incident through the lens group 202 and forms an image on the focus plate 105 when not photographing. The photographer visually confirms the image projected on the focus plate 105 with the eyepiece 120.

  The photometric circuit (AE) 106 includes a photometric sensor. Here, an image sensor such as a CCD or CMOS sensor including a plurality of pixels is used as the photometric sensor. Before the recording image is acquired, the image obtained by the photometry circuit 106 is analyzed by a digital signal processing circuit 111 described later to detect the orientation of the face of the subject. Note that a subject image formed on the focusing plate 105 is incident on the photometric sensor via the pentaprism 114.

  The focus detection circuit (AF) 107 includes a distance measurement sensor, and the distance measurement sensor outputs focus information indicating a defocus amount for each distance measurement point with a plurality of distance measurement points. The photometric sensor is divided into a plurality of areas, and the areas include distance measuring points.

  The gain switching circuit 108 is a circuit for switching the gain for amplifying the electric signal that is the output of the image sensor 102. The gain switching circuit 108 performs gain switching under the control of the camera microcomputer 101 in accordance with shooting conditions and a photographer's instruction. The A / D converter 109 converts the electrical signal that is the output of the image sensor 102 into a digital signal. A timing generator (TG) 110 synchronizes the electrical signal that is the output of the image sensor 102 and the timing of A / D conversion by the A / D converter 109.

  A digital signal processing circuit (also simply referred to as a signal processing circuit) 111 performs image processing on a digital signal that is an output of the A / D converter 109 according to a predetermined development parameter to generate image data. Here, the memory used for the processed image is omitted.

  The input unit 112 includes an operation unit including a power switch, a release switch, a setting button, and the like, and the camera microcomputer 101 performs various processes according to inputs from the input unit 112. When the release switch is operated in one step (half-pressed), the first release switch SW1 is turned ON, and the camera microcomputer 101 starts photographing preparation operations such as focus adjustment and photometry. When the release switch is operated in two steps (fully pressed), the second release switch SW2 is turned on, and the camera microcomputer 101 starts photographing operations such as exposure and development processing. Furthermore, various settings of the strobe 300 can be performed by operating a setting button provided in the input unit 112.

  The display unit 113 displays the set shooting mode of the camera, other shooting information, and the like. Note that the display unit 113 includes, for example, a liquid crystal display device and a light emitting element.

  The pentaprism 114 guides the subject image formed on the focusing plate 105 to a photometric sensor provided in the photometric circuit 106 and also to the eyepiece 120. The sub mirror 115 guides the light transmitted through the main mirror 104 to a distance measuring sensor provided in the focus detection circuit 107.

  Communication lines LC and SC are interfaces between the camera body 100, the photographing lens 200, and the strobe 300, respectively. For example, using the camera microcomputer 101 as a host, the camera body 100, the photographing lens 200, and the strobe 300 mutually exchange data and transmit commands.

  For example, as shown in FIG. 1, the communication lines LC and SC have terminals 120 and 130, respectively. The terminal 120 includes an SCLK_L terminal, a MOSI_L terminal, a MISO_L terminal, and a GND terminal.

  The SCLK_L terminal is a terminal for synchronizing communication between the camera body 100 and the photographing lens (also referred to as a lens unit) 200. The MOSI_L terminal is a terminal for transmitting data from the camera body 100 to the lens unit 200. The MISO_L terminal is a terminal for receiving data transmitted from the lens unit 200 to the camera body 100. The camera body 100 and the lens unit 200 are connected to the GND terminal.

  The terminal 130 includes an SCLK_S terminal, a MOSI_S terminal, a MISO_S terminal, and a GND terminal. The SCLK_S terminal is a terminal for synchronizing communication between the camera body 100 and the strobe 300. The MOSI_S terminal is a terminal for transmitting data from the camera body 100 to the strobe 300. The MISO_S terminal is a terminal for receiving data transmitted from the strobe 300 to the camera body 100. The camera body 100 and the strobe 300 are connected to the GND terminal.

  The photographing lens 200 has a microcomputer (LPU: lens microcomputer) 201. The lens microcomputer 201 controls the entire photographing lens 200. The lens microcomputer 201 is a one-chip IC circuit with a built-in microcomputer having, for example, a CPU, ROM, RAM, input / output control circuit, multiplexer, timer circuit, EEPROM, A / D converter, and D / A converter.

  The photographing lens 200 includes a lens group 202 having a plurality of lenses, and the lens group 202 includes at least a focus lens. The lens driving unit 203 moves at least the focus lens in the lens group 202 along the optical axis. Based on the detection output of the focus detection circuit 107, the camera microcomputer 101 calculates a drive amount for driving the lens group 202 and sends it to the lens microcomputer 201.

  The encoder 204 is for detecting the position of the lens group 202 when the lens group 202 is driven. The lens microcomputer 201 controls the lens driving unit 203 according to the driving amount calculated by the camera microcomputer 101. Then, the lens microcomputer 201 refers to the position indicated by the output of the encoder 204 to drive and control the lens group 202 to adjust the focus. A diaphragm control circuit 206 controls the diaphragm 205 under the control of the lens microcomputer 201.

  The strobe 300 has a main body part 300a that is detachably attached to the camera main body 100, and a light emitting part 300b that is held by the main body part 300a so as to be pivotable in the vertical and horizontal directions. In the following description, the rotation direction of the light emitting unit 300b will be described with the side connected to the light emitting unit 300b in the main body 300a as the upper side.

  The strobe 300 includes a microcomputer (FPU: strobe microcomputer) 310, and the strobe microcomputer 310 controls the entire strobe 300. The strobe microcomputer 310 is a one-chip IC circuit with a built-in microcomputer having, for example, a CPU, ROM, RAM, input / output control circuit, multiplexer, timer circuit, EEPROM, A / D, and D / A converter.

  The battery 301 is a power source (VBAT) of the strobe 300, and the booster circuit 302 has a booster 302a, resistors 302b and 302c used for voltage detection, and a main capacitor 302d. The booster circuit 302 boosts the voltage of the battery 301 to several hundred volts by the booster 302a and stores electric energy for light emission in the main capacitor 302d. The charging voltage of the main capacitor 302d is divided by the resistors 302b and 302c, and the divided voltage is input to the A / D conversion terminal of the flash microcomputer 310.

  The discharge tube 305 receives a pulse voltage of several KV applied from the trigger circuit 303 and is excited by the energy charged in the main capacitor 302d to emit light. Then, the light from the discharge tube 305 is irradiated to the subject or the like. The light emission control circuit 304 controls the light emission start and light emission stop of the discharge tube 305.

  The photodiode 314 receives light from the discharge tube 305 and outputs a detection output (current) corresponding to the light emission amount. The photodiode 314 receives light from the discharge tube 305 directly or through a glass fiber or the like. The integrating circuit 309 integrates the current that is the output of the photodiode 314. The output (integrated output) of the integrating circuit 309 is input to the non-inverting input terminal of the comparator 315 and the A / D converter terminal of the strobe microcomputer 310.

  The non-inverting input terminal of the comparator 315 is connected to the D / A converter output terminal of the flash microcomputer 310, and the output terminal of the comparator 315 is connected to one of the input terminals of the AND gate 311. The other input terminal of the AND gate 311 is connected to the light emission control terminal of the flash microcomputer 310, and the output terminal of the AND gate 311 is connected to the light emission control circuit 304.

  The strobe 300 is provided with a reflector unit 306a and a zoom optical system. The reflector 306 reflects light emitted from the discharge tube 305 and guides it in a predetermined direction. The zoom optical system includes an optical panel 307 and the like. The zoom optical system changes the light irradiation angle by the strobe 300. By changing the relative position (relative position) between the reflector unit 306a and the optical panel 307, the guide number and irradiation range of the strobe 300 can be changed. That is, the relative position between the optical panel 307 and the light emitting unit 300b can be changed.

  The light emitting unit 300b includes a discharge tube 305, a reflector 306, and an optical panel 307. The light distribution angle of the light emitter 300b changes according to the movement of the reflector unit 306a, and the irradiation direction of the light emitter 300b is the main body. It changes with rotation with respect to the part 300a.

  The input unit 312 has an operation unit including a power switch, a mode setting switch for setting the operation mode of the strobe 300, and setting buttons for setting various parameters. The stroboscopic microcomputer 310 performs various processes according to the input from the input unit 312. Information indicating the state of the strobe 300 is displayed on the display unit 313. Note that the display portion 313 is provided with a liquid crystal device and a light-emitting element.

  The zoom drive circuit 330 includes a zoom detection unit 330a and a zoom drive unit 330b. The zoom detection unit 330a detects the relative position between the reflector unit 306a and the optical panel 307 using an encoder or the like. The zoom drive unit 330b moves the reflector unit 306a by a motor. The flash microcomputer 310 obtains the focal length from the lens microcomputer 201 via the camera microcomputer 101, and obtains the driving amount of the reflector unit 306a according to the focal length.

  FIG. 3 is a flowchart for explaining the light emission processing of the strobe 300 shown in FIG.

  When the power switch provided in the input unit 312 is turned on and the flash microcomputer 310 becomes operable, the flash microcomputer 310 starts the flowchart shown in FIG.

  First, the flash microcomputer 310 initializes a memory and a port provided in the flash microcomputer 310 (step S301). At this time, the stroboscopic microcomputer 310 reads the state of the switch provided in the input unit 312 and preset input information, and sets the light emission mode such as the method for determining the light emission amount and the light emission timing.

  Subsequently, the flash microcomputer 310 controls the booster circuit 302 to start charging the main capacitor 302d (step S302). Thereafter, the flash microcomputer 310 stores information indicating the focal length of the lens unit 200 obtained from the camera microcomputer 101 via the communication line in the built-in memory (step S303). If the previous focal length information has been stored, the flash microcomputer 310 updates the focal length information.

  The strobe microcomputer 310 moves the reflector unit 306a by the zoom drive circuit 330 so that the light distribution angle of the strobe light is in a range corresponding to the focal length information (step S304). If it is not necessary to move the reflector unit 306a, the process of step S304 is omitted. Subsequently, the flash microcomputer 310 displays the light emission mode and focal length information set in the input unit 312 on the display unit 313 (step S305).

  The stroboscopic microcomputer 310 determines whether or not the charging of the main capacitor 302d is completed (step S306). If charging is not completed (NO in step S306), strobe microcomputer 310 waits. On the other hand, when the charging is completed (YES in step S306), the flash microcomputer 310 transmits a charging completion signal to the camera microcomputer 101, and the process proceeds to step S307.

  The flash microcomputer 310 determines whether or not a main light emission start signal, which is a main light emission instruction, is received from the camera microcomputer 101 (step S307). If the main light emission start signal is not received (NO in step S307), the flash microcomputer 310 returns to the process of step S302. On the other hand, when the main light emission start signal is received (YES in step S307), the flash microcomputer 310 controls the light emission control circuit 304 according to the main light emission start signal to cause the discharge tube 305 to perform main light emission (step S308). After the main light emission ends, the flash microcomputer 310 stores information related to the light emission such as the voltage of the main capacitor 302d in the built-in memory, and proceeds to the process of step S309.

  The flash microcomputer 310 starts continuous light emission control for controlling light emission and charging so that the temperature of the flash device 300 does not rise too much due to continuous light emission or the like (step S309). The continuous light emission control will be described later.

  This continuous light emission control is performed when a change occurs from the initial state, and ends when the state returns to the initial state. Here, the stroboscopic microcomputer 310 assumes the temperature of the target part where it is necessary to consider the influence of heat generated by light emission. Then, the flash microcomputer 310 obtains the estimated temperature of the target part from the first light emission or starts counting by a counter that is a substitute for the assumed temperature. The stroboscopic microcomputer 310 performs continuous light emission control in parallel with the light emission processing shown in FIG. 3 until the assumed temperature becomes the same as the initial state or until the counter is reset.

  The continuous light emission control is performed in the same manner for single light emission. After starting the continuous light emission control, the flash microcomputer 310 returns the light emission process to the process of step S302.

  FIG. 4 is a flowchart for explaining the continuous light emission control shown in FIG. In the continuous light emission control, the stroboscopic microcomputer 310 assumes (that is, calculates) the temperature of the target portion that needs to consider the influence of heat generated by light emission. Then, based on the calculation result, the flash microcomputer 310 controls the light emission interval and the charging current. Here, the optical panel 307 will be described as a target part. This is because the optical characteristics of the optical panel 307 may change when the temperature rapidly increases.

  As described above, when the strobe light is emitted, the strobe microcomputer 310 starts the process according to the flowchart shown in FIG. 4 in parallel with the process of the flowchart shown in FIG. First, the flash microcomputer 310 initializes settings related to continuous light emission control (step S401). Then, the flash microcomputer 310 reads preset input information. Note that when input information that has been set in advance is read in step S301 shown in FIG. 3, the process in step S401 can be omitted.

  Subsequently, the flash microcomputer 310 starts sampling for performing continuous light emission control (step S402). Here, the stroboscopic microcomputer 310 detects light emission at a predetermined sampling time and performs a calculation described later for each sampling time. In the following description, calculation in one sampling will be described. The calculation is performed for each sampling until the calculation result becomes the same as the initial state or until the reset is performed.

  Note that it is desirable to set the sampling time to be equal to or shorter than the fastest charging time when the strobe 300 is fully lit. For example, if it takes 0.8 seconds to complete charging after full light emission (charging time is 0.8 seconds), the sampling time is set to 0.5 seconds. In this case, since the light emission is performed once during one sampling time at the time of full light emission that generates the most heat, it is easy to determine the parameters for the calculation. When the charging time becomes faster due to the connection of an external power supply device or the like, the sampling time may be set to be equal to or less than the charging time.

  Even when the charging time is slow, it is better not to set the sampling time too late. Although the sensitivity of the calculation result can be lowered by setting the sampling time late, the determination of the calculation result described later is delayed by the delay. As a result, when the display or the like changes due to the control after the light emission, the display changes with a delay from the light emission, so that the user tends to feel uncomfortable.

  Next, the flash microcomputer 310 acquires the light emission energy NL by light emission during one sampling time (step S403). For example, the flash microcomputer 310 calculates the light emission energy NL based on the voltage of the main capacitor 302 d, the integral value of the light emission amount obtained from the photodiode 314, or the light emission command from the camera body 100.

  First, the case where the light emission energy NL is calculated based on the voltage of the main capacitor 302d will be described.

  When the pre-light-emission voltage of the main capacitor 302d is bVCM and the post-light-emission voltage is aVCM, the energy EC is obtained by the following equation (1) by the square difference.

The stroboscopic microcomputer 310 obtains the pre-light emission voltage bVCM and the post-light emission voltage aVCM from the A / D conversion values related to the main capacitor 302d. The strobe microcomputer 310 adjusts the output range with the gain Os according to the range that can be calculated. The stroboscopic microcomputer 310 obtains the light emission energy NL by converting the energy EC according to the following approximate expression (2) according to the output range used in the continuous light emission control calculation described later.

The coefficients α and β vary depending on the configuration of the strobe 300 and are adjusted based on measurement data obtained in advance.

  Next, the case where the light emission energy NL is calculated based on the integral value of the light emission amount obtained from the photodiode 314 will be described.

  The stroboscopic microcomputer 310 obtains the energy EC by the following equation (3) based on the peak value AL obtained after light emission.

The stroboscopic microcomputer 310 adjusts the gain Os according to the output range used in the continuous light emission control calculation described later, and treats it as energy approximately. Thereafter, the stroboscopic microcomputer 310 adjusts the output range according to the expression (2) to obtain the light emission energy NL in the same manner as the case of obtaining from the voltage of the main capacitor 302d. Note that a conversion table indicating the relationship between the integrated value AL of the light emission amount and the light emission energy NL may be stored in an EEPROM or the like, and the light emission energy NL may be obtained using the conversion table.

  The conversion is performed in the same manner when the light emission energy NL is calculated based on the light emission command sent from the camera body 100. Then, the gain Os is adjusted in accordance with an output range used in a continuous light emission control calculation described later, and is treated as an energy EC approximately.

  If the light emission command from the camera body 100 is E, the energy EC is expressed by the following equation (4).

The stroboscopic microcomputer 310 adjusts the output range according to the expression (2) to obtain the light emission energy NL in the same manner as the case of obtaining from the voltage of the main capacitor 302d. Note that a conversion table indicating the relationship between the light emission command E and the light emission energy NL may be stored in an EEPROM or the like, and the light emission energy NL may be obtained using the conversion table.

  When light is emitted a plurality of times during one sampling time due to minute light emission or the like, the emission energy NL is obtained by the total value of the plurality of times of light emission. Assuming that the light emission energies resulting from the multiple times of light emission are NL1, NL2,..., NLz, the total light emission energy NL is expressed by the following equation (5).

In step S308 shown in FIG. 3, it is assumed that the pre-light emission is handled as a series of light emission. However, in the calculation of the light emission energy NL, the pre-light emission is regarded as an individual light emission, and these pre-light emission are summed up by equation (5). However, if light emission is not performed during one sampling time, NL = 0. After obtaining the light emission energy NL, the flash microcomputer 310 stores the light emission energy NL in the built-in memory, and proceeds to step S404.

  Next, the flash microcomputer 310 calculates the control temperature addition amount Tfu (step S404). The control temperature addition amount Tfu will be described later. After calculating the control temperature addition amount Tfu, the flash microcomputer 310 stores the control temperature addition amount Tfu as a calculation result in the built-in memory.

  Subsequently, the flash microcomputer 310 calculates a control elapsed temperature Tfd (step S405). The control elapsed temperature Tfd will be described later. After calculating the control elapsed temperature Tfd, the flash microcomputer 310 stores the control elapsed temperature Tfd as a calculation result in the built-in memory.

  Next, the flash microcomputer 310 calculates the control temperature Tf (step S406). The control temperature Tf will be described later. After calculating the control temperature Tf, the flash microcomputer 310 stores the control temperature Tf as a calculation result in the built-in memory.

  Subsequently, the flash microcomputer 310 performs a control stage determination process described later (step S407). The control stage sets the shortest light emission interval when performing continuous light emission. And it sets so that the shortest light emission interval may become long as a control stage goes up. The longer the shortest light emission interval, the more limited the timing at which light can be emitted. In the control stage determination process, the control stage is determined based on whether or not the control temperature Tf obtained in step S406 exceeds a predetermined threshold value. Note that the charging current may be changed instead of setting the shortest light emission interval.

  A plurality of threshold values used in the control stage determination process can be set for each zoom position. Based on the temperature of the optical panel 307 and the exterior temperature of the light emitting unit 300b, the threshold table is stored in the EEPROM, and the threshold table is used. Adjust the threshold. Further, when the control temperature Tf rises and becomes a warning stage in the latter half of the control stage, a warning display can be performed to restrict light emission.

  If the zoom position change processing bit is set, the processing in step 407 is omitted. The bits of the zoom position change process will be described later. After the control stage determination process, the flash microcomputer 310 stores the determination result in the built-in memory.

  Next, the flash microcomputer 310 calculates a panel temperature counter Cp (step S408). The panel temperature counter Cp will be described later. After calculating the panel temperature counter Cp, the flash microcomputer 310 stores the calculation result in the built-in memory.

  Subsequently, the flash microcomputer 310 calculates the internal temperature counter Ci (step S409). The internal temperature counter Ci will be described later. After calculating the internal temperature counter Ci, the flash microcomputer 310 stores the calculation result in the built-in memory.

  Next, the flash microcomputer 310 calculates the internal cooling amount Fi (step S410). The internal cooling amount Fi will be described later. After calculating the internal cooling amount Fi, the flash microcomputer 310 stores the calculation result in the built-in memory.

  Subsequently, the flash microcomputer 310 confirms the zoom position at the time of the last light emission during one sampling time. Then, the flash microcomputer 310 determines whether or not there is a change in the zoom position by comparing the zoom position during the previous one sampling time with the current zoom position (step S411). If there is a change in the zoom position (YES in step S411), the flash microcomputer 310 performs a zoom position change process described later (step S412). Thereafter, the flash microcomputer 310 stores the zoom position change process result in the built-in memory, and proceeds to the process of step S413. If there is no change in the zoom position (NO in step S411), the flash microcomputer 310 proceeds to the process in step S413.

  The flash microcomputer 310 stores the emission energy NL and the above calculation result in the built-in memory (step S413) so that it can be used in the next calculation. If already stored, step 413 is omitted. If there is no change in the zoom position (YES in step S411), the flash microcomputer 310 lowers the bit of the zoom position change process described later and proceeds to the process in step S413.

  Subsequently, the flash microcomputer 310 determines whether or not the control temperature Tf and other calculation results have returned to the initial state. That is, here, the flash microcomputer 310 determines whether or not all the calculation results are cleared (step S414). If it is determined that the calculation result is not all cleared (NO in step S414), the flash microcomputer 310 returns to the process of step S403 and performs the next sampling. On the other hand, if it is determined that the calculation result is all cleared (YES in step S414), that is, if the operation returns to the initial state, strobe microcomputer 310 ends the continuous light emission control.

  FIG. 5 is a flowchart for explaining an example of the control stage determination process shown in FIG.

  When the control stage determination process is started, the flash microcomputer 310 determines whether or not the control temperature Tf exceeds a predetermined threshold (step S501). When a change occurs in the control stage, that is, when the control temperature Tf exceeds a predetermined threshold value, the flash microcomputer 310 updates the determination result to a new control stage. Then, the flash microcomputer 310 stores the determination result in the built-in memory.

  Subsequently, the flash microcomputer 310 determines whether or not there is a change in the control stage according to the determination result obtained in step S501 (step S502). When there is a change in the control stage (YES in step S502), the flash microcomputer 310 changes the control stage and updates the related parameters (step S503). After updating the parameters, the flash microcomputer 310 stores the parameters in the built-in memory. Then, the flash microcomputer 310 determines whether or not the control stage has risen to enter the warning stage (step S504). If there is no change in the control stage (NO in step S502), strobe microcomputer 310 proceeds to the process in step S504. In the illustrated flowchart, for example, the warning stage is set to two stages.

  If the control stage is not in the warning stage (normal in step S504), the strobe microcomputer 310 applies the normal stage judgment processing sampling time (normal time judgment processing time) (step S505).

  The determination processing sampling time indicates a sampling time for performing the control stage determination processing in step S407 shown in FIG. In normal times, it is desirable to synchronize with the sampling of continuous light emission control, but it may be shifted to prevent chattering on the display.

  The same applies to the warning stage, but if not synchronized with the continuous light emission control, this step is omitted if the sampling time of the control stage determination process is not reached when the process proceeds to step S407 shown in FIG. . Alternatively, the processes according to the flowcharts shown in FIGS. 4 and 5 may be performed in parallel, and the result of the control stage determination process at the timing when the process of step S407 is performed may be applied. Furthermore, this step may be omitted when there is no change in the sampling time for determination processing.

  After applying the sampling time for determination processing in the normal stage, the flash microcomputer 310 stores the result in the built-in memory and ends the control stage determination processing. If the process is performed in parallel with the continuous light emission control, the flash microcomputer 310 returns to the process of step S501.

  When the control stage enters the first warning stage (warning 1 in step S504), the flash microcomputer 310 applies the sampling time for determination processing in the first warning stage (step S506). In the warning stage, unlike the normal time, it is desirable to set the sampling time longer than the sampling time in the continuous light emission control. That is, since a warning display is performed in the warning stage, if the display changes in the same cycle as the continuous light emission control, it becomes a phenomenon like chattering on the display and the display becomes difficult to see. Therefore, if the sampling time at the warning stage is lengthened so that the display does not change beyond a predetermined time, the above-mentioned disadvantage is solved.

  In the warning stage, from the viewpoint of protecting the strobe 300, a restriction including prohibiting light emission is executed so that the light emission interval does not become less than the first predetermined interval. In addition, when entering the warning stage, the temperature of the optical panel 307 and the exterior temperature of the light emitting unit 300b are increased by repeating light emission. For this reason, the warning display prompts the user to dissipate heat from the strobe 300, and the sampling time at the warning stage is lengthened so that the light can be emitted only at the first predetermined interval or more. If there is no change in the sampling time for determination processing, this step may be omitted.

  After applying the sampling time for the determination process in the first warning stage, the flash microcomputer 310 stores the result in the built-in memory, and ends the control stage determination process. If the process is performed in parallel with the continuous light emission control, the flash microcomputer 310 returns to the process of step S501.

  When the control stage enters the second warning stage (warning 2 in step S504), the flash microcomputer 310 applies the sampling time for determination processing in the second warning stage (step S507). The processing in the second warning stage is the same as in the first warning stage, but the warning display is changed, and the light emission is prohibited so that it does not become less than the second predetermined interval longer than the first predetermined interval. Including restrictions are enforced. In order to further suppress the increase in the temperature of the optical panel 307 and the exterior temperature of the light emitting unit 300b, the sampling time in the second warning stage may be set longer than the sampling time in the first warning stage. . Further, when there is no change in the sampling time for determination processing, this step may be omitted.

  After applying the sampling time for determination processing at the second warning stage, the flash microcomputer 310 stores the result in the built-in memory, and ends the control stage determination processing. If the process is performed in parallel with the continuous light emission control, the flash microcomputer 310 returns to the process of step S501.

  Next, derivation of an arithmetic expression used in continuous light emission control performed by the strobe 300 shown in FIG. 1 will be described.

  FIG. 6 is a diagram for explaining an example of a heat transfer model in the optical panel 307 shown in FIG. FIG. 6A is a diagram showing thermal radiation to the optical panel 307 when the discharge tube 305 emits light, and FIG. 6B is an optical diagram from the internal space of the light emitting unit 300b after the discharge tube 305 emits light. It is a figure which shows the heat transfer with respect to the panel 307. FIG. FIG. 6C shows heat transfer from the optical panel 307 to the external space after the discharge tube 305 emits light.

  In FIG. 6A, the optical panel 307 is heated by thermal radiation when the discharge tube 305 emits light. When this amount of heat is a radiant heating amount Rh, the radiant heating amount Rh is expressed by the following equation (6) using the above-described emission energy NL.

Rhc represents a radiant heating coefficient.

  The optical panel 307 has different heat effects on the optical panel 307 at each zoom position. For this reason, the radiant heating coefficient Rhc is set for each zoom position, and the radiant heating amount Rh is obtained for each zoom position.

  In FIG. 6B, after the discharge tube 305 emits light, heat transfer to the optical panel 307 occurs from the heated internal space of the light emitting unit 300b with a time difference from the above-described heat radiation. When the heat transfer heating amount is Hh, the heat transfer heating amount Hh is expressed by the following equation (7).

Ci represents an internal temperature counter (count value), and Cp represents a panel temperature counter. pre indicates a calculation result obtained at one or more previous sampling times. Hhc represents a heat transfer coefficient when heat in the internal space of the light emitting unit 300b is transferred to the optical panel 307.

  In FIG. 6C, the optical panel 307 dissipates heat because it is in contact with the outside air. If the amount of heat radiated to the outside is the panel heat dissipation amount Fp, the panel heat dissipation amount Fp is expressed by the following equation (8).

T represents an environmental temperature or a counter (count value) that is an alternative to the environmental temperature, and Fhc represents a heat transfer coefficient when heat is transferred from the optical panel 307 to the outside.

  In addition to the heat transfer model shown in FIG. 6, there is heat conduction with the exterior, but the contact area between the optical panel 307 and the exterior is small, and the heat conduction is sufficient for the heat transfer when the discharge tube 305 emits light. Since it is small, it is omitted here.

  Here, the internal temperature counter Ci shown in the above equation (7) is obtained.

  FIG. 7 is a diagram for explaining a heat transfer model by light emission in the inner space in the light emitting unit 300b. 7A is a diagram showing heat transfer to the internal space of the light emitting unit 300b when the discharge tube 305 emits light, and FIG. 7B is an external space from the internal space of the light emitting unit 300b through the exterior. It is a figure which shows the heat transfer at the time of radiating heat.

  In FIG. 7A, the internal space of the light emitting unit 300b is heated by heat transfer when the discharge tube 305 emits light. If this calorific value is a calorific value Hv, the calorific value Hv is expressed by the following equation (9) using the emission energy NL.

Cic represents an internal temperature coefficient, which is a conversion coefficient when the light emission energy NL is converted into a calorific value Hv.

  In FIG.7 (b), heat radiation is performed from the internal space of the heated light emission part 300b. Assuming that the amount of heat radiated to the external space through the outer shell is the internal cooling amount Fi, the internal cooling amount Fi is expressed by the following equation (10).

Note that Fic indicates an internal cooling coefficient.

  The internal temperature counter Ci is the sum of the internal temperature counter preCi of the previous sampling, the heat generation amount Hv of the previous sampling, and the internal cooling amount Fi of the previous sampling. Therefore, the internal temperature counter Ci is represented by the following equation (11).

The panel temperature counter Cp is the sum of the previous sampling panel temperature counter preCp, the radiant heating amount Rh, the heat transfer heating amount Hh, and the panel heat dissipation amount Fp. Therefore, the panel temperature counter Cp is expressed by the following formula (12).

Subsequently, the assumed panel temperature is calculated using the panel temperature counter Cp and the environmental temperature T obtained by Expression (12). Assuming that the assumed panel temperature is Tps, the assumed panel temperature Tps is expressed by the following equation (13).

Tc represents a temperature conversion coefficient.

  If the environmental temperature T is known from the equation (13), the temperature of the optical panel 307 at that time can be obtained.

  FIG. 8 is a diagram showing a calculation result obtained by using the optical panel temperature actual measurement value and Expression (13), and the temperature difference therebetween.

  In FIG. 8, the horizontal axis represents the elapsed time from the start of light emission, and the vertical axis represents the surface temperature of the optical panel 307. In addition, here, as an example, the result when T = 23 and 130 times of light emission is repeated is shown. However, in the following, for simplification of control, calculation is performed with T = 0.

  Since the calculation related to the continuous light emission control is performed, if the formula (13) is arranged as a development, it can be arranged as shown by the formula (14).

Tf represents a control temperature and is used for control determination described later.

  Here, when the first term on the right side of the equation (14) is the control temperature addition amount Tfu and the second term and the third term on the right side are the control elapsed temperature Tfd, it can be expressed by the equation (15).

The control temperature addition amount Tfu is an expression relating to thermal radiation, and the heat generation of the optical panel 307 due to thermal radiation in sampling is immediately added. The control elapsed temperature Tfd is an expression relating to the temperature of the optical panel 307 in the sampling assumed from the previous sampling calculation result. The control elapsed temperature Tfd includes a panel temperature counter preCp for the previous sampling and an internal temperature counter preCi for the previous sampling. Therefore, when the calculation order in the flowchart described with reference to FIG. 4 is considered, the calculation within one sampling can be completed by the following equations (16) to (18).

In this way, the calculation is performed using the first equation of equation (15) in step S404, the second equation of equation (15) in step S405, and the third equation of equation (15) in step S406. Done. Further, the calculation is performed using Expression (16) in Step S408, Expression (17) in Step S409, and Expression (18) in Step S410.

  Further, it can be seen that Expressions (16) to (18) are calculations for feeding back to the next sampling. As a result, it is possible to obtain an estimated temperature based on the time during which heat is radiated and the temperature difference between the optical panel 307 and the internal space of the light emitting unit 300b. For example, it is possible to draw a heat dissipation curve in which the panel heat dissipation amount Fp increases when the temperature of the optical panel 307 is high, and the panel heat dissipation amount Fp decreases when the temperature is low. As a result, the assumed temperature can be calculated so as to follow the actual temperature rise and temperature change during heat dissipation. As shown in FIG. 8, the change tendency of the assumed panel temperature Tps, which is the calculation result obtained by using the above formula, is approximate to the change tendency of the optical panel temperature actual measurement value, and the assumed panel temperature Tps is expressed as the optical panel temperature. There is no problem even if it is used instead of the actual measurement value. Thus, in this embodiment, it is not necessary to use a temperature sensor, and cost can be reduced.

  FIG. 9 is a flowchart for explaining the zoom position changing process shown in FIG.

  When the zoom position change process is started, the flash microcomputer 310 reads a determination threshold value of the control temperature Tf related to the control stage at the zoom position before the zoom position change from a built-in memory (for example, EEPROM) (step S901). Whether the upper limit value or the lower limit value of the determination threshold value is used depends on the threshold value stored in the EEPROM, but when the lower limit value is used, the threshold value at the first stage of the control stage is zero. In this case, a threshold value that is one level higher than the control level may be used.

  Subsequently, the flash microcomputer 310 reads from the built-in memory a determination threshold value for the control temperature Tf related to the control stage at the zoom position after the zoom position change (step S902). Whether to use the upper limit value or the lower limit value of the determination threshold needs to be the same as in step S901.

  Next, the flash microcomputer 310 performs a change process on the panel temperature counter Cp obtained by the process of step S408 shown in FIG. 4 (step S903). This process is performed because the range of the control stage at each zoom position is different. The panel temperature counter after the change process can be obtained by the following equation (19) using equation (16), where the pre-conversion threshold is FPZ and the post-conversion threshold is FAZ.

After the conversion process, the flash microcomputer 310 stores the result of the conversion process in the built-in memory. Then, the flash microcomputer 310 performs a change process on the internal temperature counter Ci obtained by the process of step S409 in the same manner as the process of step S903 (step S904). The internal temperature counter after the change process can be obtained by the following equation (20) using equation (17), where the pre-conversion threshold is FPZ and the post-conversion threshold is FAZ.

After the conversion process, the flash microcomputer 310 stores the result of the conversion process in the built-in memory. The flash microcomputer 310 stores the result of the conversion process in the built-in memory in association with the changed zoom position (step S905) so that it can be used for the next sampling. Thereafter, the flash microcomputer 310 ends the zoom position changing process.

  At this time, the flash microcomputer 310 adds a bit indicating that the zoom position has been changed. When the bit is added, the flash microcomputer 310 does not perform the determination process in step S407 shown in FIG. That is, as a result of feedback being performed in the continuous light emission control, 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. Become. If the control stage determination is performed at this stage, the control stage may temporarily deviate from the normal value, and thus the flash microcomputer 310 does not perform the determination process of step S407.

  Here, a process when the power switch provided in the input unit 312 is turned off during the above-described continuous light emission control process will be described. In addition, the following description is applied when the type that physically cuts the power supply by the power switch provided in the input unit 312 is excluded. For example, it is applied when the flash microcomputer 310 turns off the power supply by turning off the power switch. Further, even when the power supply from the main power supply is cut by the built-in power supply, the flash microcomputer 310 is applied when the power supply is not completely cut off.

  In the process of step S414 shown in FIG. 4, it is determined that the control temperature Tf and other calculation results have not returned to the initial state, and the power switch is turned off when the continuous light emission control process is continued. In this case, the flash microcomputer 310 stores various settings in the built-in memory (EEPROM) and enters a temporary sleep state.

  Here, if the continuous light emission control process is reset, a large difference occurs between the control temperature Tf and the actual optical panel temperature. For this reason, the strobe microcomputer 310 is temporarily activated at every predetermined calculation sampling time during the continuous light emission control process. Then, the flash microcomputer 310 performs the calculation as described above, and returns to the sleep state again when the calculation is completed.

  However, the display on the display unit 313 is not performed, and the apparently turned off state is continued. Thus, it is possible to continue the continuous light emission control process while minimizing power consumption. When the control temperature Tf and other calculation results return to the initial state, the flash microcomputer 310 shifts to a normal power-off state.

  In this manner, in the first embodiment of the present invention, it is possible to protect the target portion such as the optical panel from the heat generated by the light emission by controlling the light emission by the light emitting unit to prevent an abnormal temperature rise.

[Second Embodiment]
Next, an example of a camera including a strobe according to the second embodiment of the present invention will be described.

  FIG. 10 is a block diagram showing the configuration of an example of a camera including a strobe according to the second embodiment of the present invention. In FIG. 10, the same components as those of the camera shown in FIG. In the illustrated camera, an external power supply device 400 is connected to a strobe 380, and the main capacitor 302d can be charged by the external power supply device 400.

  The strobe 380 has an external power supply detection circuit 340, and the external power supply detection circuit 340 processes power supply and signals from a communication line SB described later. The communication line SB is an interface signal line between the strobe 380 and the external power supply device 400. For example, the terminal 350 provided in the communication line SB has a signal terminal SEH, a high-voltage power input terminal HV, and a GND terminal. The signal terminal SEH is used for inputting and outputting signals for controlling the strobe 380 and the external power supply apparatus 400. The high voltage power input terminal HV is used to supply power to the main capacitor 302d. The strobe 380 and the external power supply device 400 are connected to the GND terminal.

  The external power supply apparatus 400 includes a microcomputer (external power supply microcomputer: FPU) 410, and the external power supply microcomputer 410 controls the entire external power supply apparatus 400. The external power supply microcomputer 410 is a one-chip IC circuit with a built-in microcomputer having, for example, a CPU, ROM, RAM, input / output control circuit, multiplexer, timer circuit, EEPROM, A / D, and D / A converter.

  The battery 401 is used as a power supply (VBAT) for the external power supply apparatus 400. The voltage of the battery 401 is boosted to several hundred volts by the boosting unit 402, and then applied to the strobe 380 via the communication line SB to accumulate electric energy in the main capacitor 302d. The strobe detection circuit 440 processes power supply and signals via the communication line SB.

  FIG. 11 is a flowchart for explaining the continuous light emission control performed by the strobe 380 shown in FIG. In FIG. 11, the same steps as those in the flowchart shown in FIG.

  After the process of step S402, the flash microcomputer 310 confirms whether or not the external power supply device 400 is connected to the flash 380 by the external power supply detection circuit 340. Here, the external power supply detection circuit 340 obtains the type (model) and ID information of the external power supply device 400 connected via the signal terminal SEH as external power supply information and sends it to the flash microcomputer 310. Then, the flash microcomputer 310 stores the external power supply information in the built-in memory, and proceeds to the above-described processing of step S403.

  After the process of step S408, the flash microcomputer 310 calculates an internal temperature counter Ci (step S1110). When the external power supply device 400 is connected, the flash microcomputer 310 changes the gain for obtaining the light emission energy NL according to the external power supply information. As a result, the flash microcomputer 310 controls the flashable number of times (that is, the number of times of continuous light emission), the charging current, and the like, thereby protecting the flash 380 and the external power supply device 400. Then, after calculating the internal temperature counter Ci, the flash microcomputer 310 stores the calculation result in the built-in memory, and proceeds to the process of step S410.

  Next, derivation of an arithmetic expression used in continuous light emission control performed by the strobe shown in FIG. 10 will be described.

  When the coefficient for each zoom position is simplified with respect to the above-described Expressions (15) to (18), it can be expressed by the following Expression (21).

The coefficients γ, δ, ε, ζ, η, κ, λ, ν, ξ, and ρ vary depending on the material, configuration, and space size of the strobe 380, and are adjusted based on the measurement data obtained in advance. To do.

  In Expression (21), from the first and fifth expressions, γ and ν are treated as gains related to the emission energy NL. In the equation (21), the first equation takes into account the instantaneous influence of thermal radiation, so that it is not fed back at the next sampling. On the other hand, it is possible to adjust the gain by taking into consideration the effect of heat transfer of the internal temperature counter Ci in the next sampling by the gain ν of the fifth equation. As a result, the control temperature Tf can be increased rapidly by making it appear that the operation has generated a large amount of heat.

  For example, the external power supply detection circuit 340 detects whether the external power supply apparatus 400 is connected, and changes the gain ν based on the detection result. This makes it possible to adjust the number of times the strobe 380 can emit light and the charging current. Further, the flash microcomputer 310 may change the gain ν according to the external power supply information obtained by the external power supply detection circuit 340. As a result, even when the external power supply apparatus 400 having low thermal characteristics is connected, the external power supply apparatus 400 can be operated without being damaged by changing the gain ν.

  Furthermore, if the gain ν of the fifth equation in equation (21) is changed for each control stage, it is possible to adjust the operation at the time of rapid temperature rise and the warning stage regardless of the presence or absence of the external power supply device 400. For example, the gain ν is changed for each control stage in order to prevent display chattering in a warning stage when a sudden temperature rise occurs even in a short light emission interval in one stage of control.

  FIG. 12 is a diagram showing an example of an operation at a warning stage for preventing chattering on the display in the strobe shown in FIG.

  In FIG. 12, the case where the light emission interval is about 8 seconds is one warning stage, and the case where the light emission interval is about 20 seconds is two warning stages. Normally, when the temperature of the optical panel 307 is controlled, so-called display chattering occurs near the threshold value. On the other hand, as shown in FIG. 12, it is assumed that the temperature of the optical panel 307 has risen and the warning has two stages. At this time, by setting the sampling time for determination processing and the gain ν, it is possible to perform an operation of shifting from the warning level 2 to the warning level 1 when the temperature of the optical panel 307 is lowered to some extent.

  Furthermore, when the temperature of the optical panel 307 rises due to continuous light emission, it is possible to perform the operation of shifting to the second warning stage, and chattering on display or control can be prevented.

  As described above, in the second embodiment of the present invention, since the gain ν is changed for each control stage, the operation in the sudden temperature rise or warning stage is adjusted regardless of the connection of the external power supply device 400. Is possible. Thereby, it is possible to prevent a sudden temperature rise due to a short light emission interval in the first control stage or to prevent chattering on the display in the warning stage.

[Third Embodiment]
Next, an example of a camera including a strobe according to the third embodiment of the present invention will be described.

  FIG. 13 is a diagram showing the configuration of an example of a camera including a strobe according to the third embodiment of the present invention. In FIG. 13, the same components as those in the camera shown in FIG.

  The illustrated camera differs from the camera shown in FIG. 1 in that the strobe 390 includes an internal temperature measurement unit 360, an outside air temperature measurement unit 361, and an illuminance measurement unit 362. In the third embodiment, continuous light emission control is performed based on the output results of the internal temperature measurement unit 360, the outside air temperature measurement unit 361, and the illuminance measurement unit 362.

  The internal temperature measurement unit 360 includes a temperature sensor that measures the internal temperature of the light emitting unit 300b. The outside air temperature measurement unit 361 has a temperature sensor that measures the outside air temperature at a position where the strobe 390 is hardly affected by heat. The illuminance measurement unit 362 includes an illuminance sensor that measures the illuminance when the discharge tube 305 emits light.

  Here, an arithmetic expression used in the continuous light emission control of the strobe 390 will be described.

  In step S <b> 403 shown in FIG. 4, the flash microcomputer 310 calculates the light emission energy NL based on the output result of the illuminance measurement unit 362. When the output result of the illuminance measuring unit 362 is illuminance Il, the energy EC is obtained by the following equation (22).

The coefficients ω and ψ differ depending on the configuration of the strobe 390 and are adjusted based on measurement data measured in advance.

  By substituting equation (22) into equation (2), emission energy NL is obtained.

  In step S409 shown in FIG. 4, the flash microcomputer 310 calculates the internal temperature counter Ci based on the output result of the internal temperature measurement unit 360. When the output result of the internal temperature measurement unit 360 is internal Ti, the internal temperature counter Ci is obtained by the following equation (23).

The coefficients σ and τ vary depending on the configuration of the strobe 390 and are adjusted based on measurement data measured in advance.

  Further, the assumed panel temperature Tps can be obtained using the equation (13) and the environmental temperature T that is the output result of the outside air temperature measurement unit 361. Accordingly, by correcting the calculation result of the control temperature Tf, continuous light emission control can be performed in accordance with the environmental temperature T.

  As described above, in the third embodiment of the present invention, the continuous light emission control is performed based on the output results of the internal temperature measurement unit 360, the external air temperature measurement unit 361, and the illuminance measurement unit 362 provided in the strobe 390.

  In the above-described embodiment, the stroboscopic microcomputer has been described as a one-chip IC circuit with a built-in microcomputer, but a circuit such as a dedicated arithmetic unit may be provided. Furthermore, the above flowchart is an example, and the processing may be executed in a different order from the above flowchart as necessary.

  As is apparent from the above description, in the example shown in FIG. 1, the strobe microcomputer 310 functions as a first calculation unit, a second calculation unit, and a control unit.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to these embodiment, Various forms of the range which does not deviate from the summary of this invention are also contained in this invention. .

  For example, the function of the above embodiment may be used as a control method, and this control method may be executed by the lighting device. Further, a program having the functions of the above-described embodiments may be used as a control program, and the control program may be executed by a computer included in the lighting device. The control program is recorded on a computer-readable recording medium, for example.

[Other Embodiments]
A program that realizes one or more functions of the above-described embodiments is supplied to a system or apparatus via a network or a storage medium. The present invention can also be realized by a process in which one or more processors in the computer of the system or apparatus read and execute the program. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

100 camera body 101 camera microcomputer 200 photographing lens (lens unit)
201 Lens microcomputer 300 Strobe 300a Main unit 300b Light emitting unit 310 Strobe microcomputer 400 External power supply device 410 External power supply microcomputer

Claims (10)

Light emitting means;
First calculating means for obtaining light emission energy when the light emitting means emits light;
Second calculating means for obtaining a temperature rise due to light emission of the light emitting means;
Control means for controlling light emission by the light emitting means based on the light emission energy and the temperature rise;
A lighting device comprising:   The lighting device according to claim 1, wherein the control unit controls light emission by the light emitting unit according to the number of times of continuous light emission of the light emitting unit.   3. The control unit according to claim 1, wherein the control unit obtains a temperature of a target part based on the light emission energy and the temperature rise, and controls light emission by the light emitting unit based on the temperature of the target part. The lighting device described. The light emitting means is held so as to be able to change a relative position with the target part,
The lighting device according to claim 3, wherein the control unit controls light emission by the light emitting unit based on a relative position between the light emitting unit and the target part.   The control unit controls light emission by the light emitting unit based on a threshold value for controlling a light emission interval or a charging current according to a relative position between the light emitting unit and the target part. The lighting device described. Detecting means for detecting whether or not an external power supply device is connected to the lighting device;
The control means controls light emission by the light emission means based on a threshold value for controlling a light emission interval or a charging current according to a relative position between the light emission means and the target portion, and based on a detection result by the detection means. The lighting device according to claim 4, wherein the threshold value is changed. Detecting means for detecting whether or not an external power supply device is connected to the lighting device;
The lighting device according to claim 1, wherein the control unit changes a gain when the light emitting unit emits light according to a detection result of the detection unit. Imaging means for capturing an image of a subject via an imaging optical system to obtain an image;
The lighting device according to any one of claims 1 to 7,
An imaging device comprising: A first calculation step for obtaining light emission energy when the light emitting means emits light;
A second calculating step for obtaining a temperature rise due to light emission of the light emitting means;
A control step of controlling light emission by the light emitting means based on the light emission energy and the temperature rise;
A method for controlling a lighting device, comprising: A control program used in a lighting device having a light emitting means,
A computer included in the lighting device,
A first calculation step of obtaining light emission energy when the light emitting means emits light;
A second calculating step for obtaining a temperature rise due to light emission of the light emitting means;
A control step of controlling light emission by the light emitting means based on the light emission energy and the temperature rise;
A control program characterized by causing