JP4801878B2 - Lighting device - Google Patents

Description

  The present invention relates to a lighting device using a semiconductor light emitting element.

  In recent years, high-brightness LEDs, white LEDs, and the like have been developed in the field of semiconductor light-emitting devices, and their application range has expanded. For example, there is a camera flash device that uses an illumination device including a plurality of LEDs in place of a conventionally used xenon discharge tube. This is because problems such as a xenon discharge tube that requires a capacitor for driving, a space in the camera being narrowed, and a danger due to high voltage flow can be eliminated by using LEDs.

By the way, the light emitted from the flash device is ideally close to sunlight. Therefore, as a light source of the flash device, a white LED that emits white light by combining a blue LED and a phosphor, applying blue light emitted from the blue LED to the phosphor, causing secondary light emission, and the like is used. Since such white LEDs have insufficient light emission luminance to be used alone, a plurality of white LEDs are used (for example, Patent Document 1).
JP 2002-148686 A

  However, since the blue light emitted from the blue LED used in each white LED has a variation in peak wavelength, and the phosphors have individual differences, the white light emitted from each white LED has a variation in color temperature. is there. Further, since the LEDs are driven by current, the white light of each white LED has a variation in illuminance according to individual differences, and there is a problem that uneven illumination occurs when the subject is irradiated.

  Further, when the current value of the supplied current is increased in order to compensate for the low luminance of the white LED alone, the amount of heat generated by each white LED increases, and thus it is necessary to dissipate heat. If this heat dissipation is insufficient, there is a problem that the variation in luminance of each white LED and the variation in the peak wavelength of the blue light described above are amplified.

  Furthermore, since the LED has a small diameter, the flash device is a point light source with a small diameter. When such a small-diameter point light source emits high-luminance white light, if the subject is a human, the emitted light forms an image in the eye, causing damage to the retina of the eye.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems, and an object of the present invention is to provide good illumination light without uneven color temperature and uneven illumination in an illumination device using LEDs.

  An illumination device according to the present invention includes a plurality of semiconductor light emitting elements, a housing that holds the plurality of semiconductor light emitting elements so that the optical axes of the respective emitted lights face the same direction, and a housing along a plane that intersects the optical axes. And a housing driving means for displacing the body.

  The plurality of semiconductor light emitting elements are arranged, for example, along the circumferential direction or along the linear direction on the side surface of the housing parallel to the plane described above.

  When the plurality of semiconductor light emitting elements are arranged along the circumferential direction, the casing driving means may rotate the casing around, for example, the central axis in the circumferential direction, and each other along the plane described above. The housing may be displaced along two orthogonal axes.

  Further, when the plurality of semiconductor light emitting elements are arranged along the linear direction, the housing driving means has a housing around an axis extending in a direction perpendicular to the plane at the approximate center of the plurality of semiconductor light emitting elements. May be rotated, and the housing may be displaced along two mutually perpendicular axes along the plane described above.

  Preferably, a heat radiating means for radiating heat generated by the semiconductor light emitting element is provided. The heat radiating means may be an air guide port formed on a side surface intersecting with a side surface on which a plurality of semiconductor light emitting elements are disposed, or may be a fluid disposed in the housing.

  As described above, according to the present invention, a plurality of semiconductor light emitting elements are held in a casing so that the optical axes of the respective emitted lights are directed in the same direction, and such a casing is displaced along a plane intersecting the optical axis. It is done. Accordingly, light emitted from the plurality of semiconductor light emitting elements is mixed on the subject surface. As a result, the color temperature and illumination unevenness caused by individual differences of the semiconductor light emitting elements are eliminated.

  FIG. 1 is a block diagram of a camera to which the first embodiment of the present invention is applied. The CPU 10 controls the entire camera. When a power button provided on a camera body (not shown) is operated and the main switch SWMAIN is turned on, supply of power is started. When a shutter button (not shown) provided on the camera body is half-pressed, the photometry switch SWS is turned on. When the photometry switch SWS is turned on, the CPU 10 executes photometry processing and distance measurement processing. That is, the exposure value is calculated based on the input from the photometric device 11, and the aperture value, shutter speed, and charge accumulation time of the image sensor 13 necessary for photographing are calculated based on the exposure value. Further, a driving amount of a focusing lens (not shown) is calculated based on an input from the distance measuring device 12 and a driving signal is output to the focus driving circuit 14.

  When the shutter button is fully pressed, the release switch SWR is turned on. When the release switch SWR is turned on, the CPU 10 drives the shutter unit drive circuit 15 according to the aperture value calculated by the photometry process, and outputs a control signal to the image sensor drive circuit 16 according to the charge accumulation time. The shutter unit drive circuit 15 outputs a drive signal to the shutter unit 17 in accordance with the input control signal. The image sensor drive circuit 16 outputs a drive signal to the image sensor 13 in accordance with the input control signal. The image sensor 13 photoelectrically converts an optical image of a subject formed in the light receiving area and outputs an analog image signal. The A / D converter 18 A / D converts the analog image signal and outputs the digital image signal to the CPU 10.

  The digital image signal input to the CPU 10 is temporarily stored in the DRAM 19 as image data. The stored image data is appropriately read from the DRAM 19 when performing predetermined image processing. The EEPROM 20 stores various data for controlling the camera. When the main power of the camera is turned on, various data are read from the EEPROM 20, stored in the RAM in the CPU 10, and used for control by the CPU 10.

  An LCD 21 provided on the back of the camera body is connected to the CPU 10. Various data such as shooting conditions and date are displayed on the LCD 21 under the control of the CPU 10.

  As a result of photometry by the photometry device 11, when it is determined that the amount of subject light is insufficient, the CPU 10 outputs a flash drive control signal to the flash drive mechanism 22.

  FIG. 2 is a perspective view schematically showing the light emitting unit 50 constituting the flash drive mechanism 22. The light emitting unit 50 includes an annular and hollow holding housing 60 and a rotating shaft 70 provided coaxially on the axis of the holding housing 60. Six white LEDs 80 are provided on the flat surface 61 of the holding housing 60. The white LEDs 80 are arranged at equal intervals along the circumferential direction on the plane 61. A plurality of air guide holes 63 are formed on the side surface 62 of the holding housing 60 that intersects the flat surface 61 over the entire circumference. The air guide port 63 is a rectangular opening. A rectangular air guide piece 63 </ b> A that is inclined toward the inside of the holding housing 60 at a predetermined angle is provided at an edge along the axis of the holding housing 60 among the edges of the air guide opening 63. . The plurality of air guide pieces 63A are provided so that the inclination directions thereof are the same. The power supply unit 90 is provided with a power supply that supplies a drive current to the white LED 80.

  FIG. 3 is a plan view showing an internal configuration of the holding housing 60, and FIG. 4 is a partial cross-sectional view of the holding housing 60. 4 corresponds to a cross-sectional view taken along line IV-IV in FIG. As shown in FIG. 4, the disk-shaped connecting plate 64 is fixed in the vicinity of the upper end portion of the rotating shaft 70 at the center thereof, and is fixed to the holding housing 60 at the peripheral portion thereof. The ring-shaped positive electrode 65 is disposed along the circumferential direction on the inner peripheral surface of the holding housing 60. The ring-shaped negative electrode 66 is fitted in the vicinity of the lower end portion of the rotating shaft 70. The lead wire of each white LED 80 is connected to the positive electrode 65 and the negative electrode 66. Note that FIG. 3 is shown with the connecting plate 64 removed in order to clearly show the inside of the holding housing 60, and FIG. 4 is slightly enlarged compared to FIG.

  The electric brush 67 connected to the positive side of the power supply in the power supply unit 90 is supported by a support member (not shown) so as to contact the inner peripheral surface of the positive electrode 65. Similarly, the electric brush 68 connected to the negative side of the power source is supported by a support member (not shown) so as to contact the outer peripheral surface of the negative electrode 66. The negative electrode 66, the rotating shaft 70, and the electric brush 68 are electrically connected, and the current that has passed through the white LED 80 passes through the connecting plate 64, the rotating shaft 70, the negative electrode 66, and the electric brush 68 to the negative side of the power source. It flows to.

  When the rotation shaft 70 is rotated by a drive mechanism (not shown), the rotational movement is transmitted to the holding housing 60 via the connecting plate 64, and the holding housing 60 rotates about the rotation shaft 70. Since the positive electrode 65 and the negative electrode 66 have a ring shape as described above, the electric brush 67 is always in contact with the inner peripheral surface of the positive electrode 65 while the holding housing 60 is rotating, and the electric brush 68 is always The negative electrode 66 is in contact with the outer peripheral surface. Therefore, the white LED 80 can be driven even while the holding housing 60 is rotating.

  FIG. 5 is a block diagram of the flash drive mechanism 22. The control signal for the flash drive mechanism 22 output from the CPU 10 includes a control signal for controlling the light emission of each white LED 80 and a control signal for rotationally driving the holding housing 60. The light emission control signal is controlled to a predetermined duty ratio in the PWM circuit 101 and input to the drive pulse generation circuit 102. In the drive pulse generation circuit 102, the pulse amplitude is controlled. The drive signal output from the drive pulse generation circuit 102 is output to the white LED 80 of the light emitting unit 50 via the power MOSFET 103 and the resistor R. As a result, the white LED 80 is driven to emit white light. In addition, a motor 104 a for rotating the rotary shaft 70 is connected to the housing driving circuit 104. A control signal for driving the holding housing 60 is output to the motor 104a as a drive signal by the housing driving circuit 104, and as a result, the motor 104a is driven. The motor 104a is connected to an encoder 104b that detects the rotation of the motor. A rotation detection signal from the encoder 104b is input to the CPU 10 via the housing drive circuit 104, and is used for grasping the rotation speed and rotation state of the motor and driving control.

  FIG. 6 and FIG. 7 are flowcharts showing a photographing processing procedure in the camera to which the first embodiment is applied. In step S100, ON / OFF of the photometric switch SWS is checked. If it is confirmed that the above shutter button is pressed halfway and the photometric switch SWS is turned on, the process proceeds to step S102. In step S102, the above-mentioned photometric process based on the measurement result of the photometric device 11 is executed. Based on the result of this photometric processing, an exposure value is calculated in step S104, and a shutter speed is calculated in step S106.

  Next, in step S108, whether the release switch SWR is on or off is checked. If it is confirmed that the shutter button is fully pressed and the release switch SWR is turned on, the process proceeds to step S110.

  In step S110, it is determined whether it is necessary to irradiate flash light based on the result of the photometric process in step S102. When the brightness of the subject is sufficient and it is not necessary to irradiate the flash light, the process proceeds to step S112 and the subject image photographing process is started. In step S112, driving of the shutter is started. In step S114, the imaging element is driven, and photoelectric conversion processing of the optical image of the subject is executed. When the charge accumulation time calculated based on the photometric result has elapsed, the shutter drive is stopped in step S116, the drive of the image sensor 13 is then stopped in step S118, the subject image capturing process is terminated, and the process returns to step S100. .

  On the other hand, if it is determined in step S110 that the brightness of the subject is insufficient and the flash light needs to be irradiated, the process proceeds to step S120 in FIG. In step S120, rotation driving of the rotation shaft 70 of the holding housing 60 by the housing driving circuit 104 is started. In step S122, it is checked based on the detection signal of the encoder 104b whether or not the rotation of the rotary shaft 70 is stable. If it is confirmed that the rotation is stable, the process proceeds to step S124. In step S124, a driving current is supplied to each white LED 80 in the flash drive mechanism 22 described above, and light emission is started. As a result, flash light is supplied to the subject. Next, in steps S126 to S130, processing similar to that in steps S112 to S116 described above is performed. That is, the shutter driving is started in step S126, the image sensor is driven in step S128, and when the calculated charge accumulation time has elapsed, the shutter driving is stopped in step S130.

  Next, in step S132, whether the release switch SWR is on or off is checked. If it is confirmed that the shutter button is fully pressed and the release switch SWR remains on, the process returns to step S126, and the above-described photographing process is repeatedly executed.

  If it is confirmed in step S132 that the release switch SWR is OFF, the process proceeds to step S134. In step S134, the supply of the drive current to the white LED 80 is stopped, the light emission from the white LED 80 is stopped, and the supply of flash light is stopped. Next, the process proceeds to step S136, and the rotation driving of the rotating shaft 70 by the housing driving circuit 104 is stopped. If it is confirmed in step S138 that the rotation of the rotary shaft 70 has been stopped, the process proceeds to step S140. In step S140, the driving of the image sensor 13 is stopped, the subject image capturing process is terminated, and the process returns to step S100.

  As described above, in the first embodiment, the holding housing 60 is rotationally driven while the shutter is opened, that is, in conjunction with the supply of flash light.

  Here, the rotation speed of the rotation of the holding housing 60 executed in steps S120 to S136 will be described. First, the moving pitch of the white LEDs 80 for mixing the emitted light of the white LEDs 80 arranged at a predetermined pitch on the subject surface will be considered. In the example shown in FIG. 8, the distance A from the white LED 80 to the subject surface L is 10 cm (centimeter), and the arrangement pitch B of the white LEDs 80 is 2 cm. Further, when the emitted light of the white LED 80 is projected onto the subject surface L, the angle θ formed by the outer edge of the emitted light and the optical axis OP is 5.7 °. That is, the light emitted from the white LED 80 has a spread of 11.4 ° (2θ). In this case, the irradiation area on the subject surface L has a radius of 1 cm from the optical axis OP of the emitted light. Therefore, as shown in FIG. 8, the irradiation area of the adjacent white LED 80 is in contact with the subject surface L. In this case, if the white LEDs 80 are moved at a pitch of 1 cm (moving pitch C) along the straight line on which the white LEDs 80 are arranged, the illumination light is mixed on the subject surface L.

  As shown in FIG. 9, when the above-mentioned angle θ is 8.5 °, that is, when the emitted light of the white LED 80 has a spread of 17.0 °, the irradiation area on the subject surface L is the light of the emitted light. It has a radius of 1.5 cm from the axis OP. Therefore, as shown in FIG. 9, the distance from the irradiated area of the adjacent white LED 80 is 1 cm on the object plane L. In this case, if the white LEDs 80 are moved at a pitch of 1 cm (moving pitch C) in one direction along the straight line on which the white LEDs 80 are arranged, the illumination light is uniformly mixed on the subject surface L. Further, if the white LED 80 is vibrated at a pitch of 0.5 cm along the straight line on which the white LEDs 80 are arranged, the illumination light is uniformly mixed on the subject surface L.

  As shown in FIG. 10, when the above-described angle θ is 14.0 °, that is, when the emitted light of the white LED 80 has a spread of 28.0 °, the irradiation area on the subject surface L is the light of the emitted light. It has a radius of 2.5 cm from the axis OP. Therefore, as shown in FIG. 10, the distance from the irradiation region of the two adjacent white LEDs 80 is 1 cm on the subject plane L. In this case, if the white LEDs 80 are moved at a pitch of 1 cm (moving pitch C) in one direction along the straight line on which the white LEDs 80 are arranged, the illumination light is uniformly mixed on the subject surface L. Further, if the white LED 80 is vibrated at a pitch of 0.5 cm along the straight line on which the white LEDs 80 are arranged, the illumination light is uniformly mixed on the subject surface L.

  As shown in FIG. 11, when the above-mentioned angle θ is 11.3 °, that is, when the emitted light of the white LED 80 has a spread of 22.6 °, the irradiation area on the subject surface L is the light of the emitted light. It has a radius of 2 cm from the axis OP. Therefore, the irradiation area of the adjacent white LED 80 is uniformly mixed in the subject surface L. In this case, there is no need to move the white LED 80. That is, the movement pitch C is “0”.

  As described above, when the arrangement pitch B of the white LEDs 80 is 2 cm, when the white LEDs 80 are moved only in one direction and the illumination light is mixed uniformly, the movement pitch C may be set in the range of 0 to 1 cm. . Further, when the white LEDs 80 are moved in two directions opposite to each other with the same arrangement pitch B, that is, when they are vibrated, the movement pitch C may be set in the range of 0 to 0.5 cm.

  Generalizing the relative relationship between the arrangement pitch B and the movement pitch C is as follows. That is, when the arrangement pitch B of the white LEDs 80 is “n”, the movement pitch C for moving the white LEDs 80 only in one direction and uniformly mixing the illumination light on the subject surface is “0 to 0.5n”. The moving pitch C for vibrating and uniformly mixing the illumination light is “0 to 0.25 n”.

  By the way, the examples of FIGS. 8 to 11 described above are cases where the spread of the illumination light on the subject surface is equal to or more than ¼ of the arrangement pitch B of the white LEDs 80. When the spread of the illumination light on the subject surface is smaller than ¼ of the arrangement pitch B of the white LEDs 80, for example, when the spread of the emitted light of the white LED 80 is 2.85 °, the irradiation area on the subject surface L is the emitted light. And a radius of 0.25 cm from the optical axis OP. Therefore, in order to mix the illumination light uniformly, a movement amount of 1.5 cm for rotation and 0.75 cm for vibration is required, and the movement pitch C “with respect to the generalized arrangement pitch B“ n ”described above is required. The relative relationship of “0-0.5n” does not apply. Therefore, in the first embodiment, it is desirable that the spread of the illumination light on the subject surface is equal to or more than a quarter of the arrangement pitch B of the white LEDs 80.

  In the first embodiment, the white LEDs 80 are arranged at equal intervals along the circumferential direction. Based on the relationship between the arrangement pitch and movement pitch of the white LEDs 80 for mixing the illumination light described above, when the number of white LEDs arranged in the holding case 60 is m, the holding case for mixing the illumination light is used. The rotation angle θr of the body 60 is obtained from the equation (1).

    θr = 360 / (2 × m) (1)

  Further, the vibration angle θr of the holding housing 60 for mixing the illumination light can be obtained from Expression (2).

    θr = 360 / (4 × m) (2)

  In the first embodiment, six white LEDs 80 are arranged at equal intervals along the circumferential direction. Therefore, the angle at which the holding housing 60 is rotated while the shutter is open is 30 ° from the equation (1). That is, if the holding housing is rotated at a speed rotated by 30 ° while the shutter is opened, the illumination light is uniformly mixed on the subject surface. Moreover, the angle which vibrates the holding | maintenance housing | casing 60 while the shutter is open | released will be 15 degrees from Formula (2). By rotating or vibrating the holding housing 60 in this manner, variations in color temperature and illuminance of illumination light on the subject surface, which are caused by individual differences of the white LEDs 80, are eliminated.

  When the holding housing 60 rotates or vibrates, the air is guided to the air guide piece 63 </ b> A from the above-described air guide port 63 and air flows into the holding housing 60, and air convection occurs in the holding housing 60. Therefore, even if the drive substrate of the white LED 80 generates heat as the white LED 80 is driven, it is dissipated by air convection.

  Even if the brightness of the emitted light from each white LED 80 is increased to increase the illuminance of the illumination light, the plurality of white LEDs 80 are displaced with the rotation of the holding housing 60. Safe without adverse effects on the retina.

  Furthermore, in the first embodiment, since the white LEDs 80 are arranged so as to be adjacent to each other in the rotation direction, the holding housing 60 can be further downsized. As a result, it is possible to cope with high-speed driving.

  FIG. 12 is a perspective view of the holding housing 110 to which the second embodiment of the present invention is applied, and FIG. 13 is a plan view of the holding housing 110. The holding housing 110 has a hollow, substantially quadrangular prism shape. A rotation shaft 120 is provided on the flat surface 111 of the holding housing 110 in the center in the longitudinal direction. The rotating shaft 120 extends in a direction orthogonal to the plane 111. Three white LEDs 80 are arranged at equal intervals on the left and right of the rotation shaft 120 in the plane 111. The holding housing 110 can rotate around the rotation shaft 120.

  In the holding housing 110, air guide holes 114 and 115, which are rectangular openings, are formed on the side surfaces 112 and 113 that intersect the plane 111. A rectangular air guide piece 114 </ b> A that is inclined at a predetermined angle toward the inside of the holding housing 110 is disposed at an edge portion in the longitudinal direction of the air guide port 114. 114 A of air guide pieces are provided so that each inclination direction may become the same. Further, in the air guide opening 115, a similar air guide piece 115A is disposed at an edge portion along a direction orthogonal to the longitudinal direction. Although not shown in FIG. 12, an air guide port similar to the air guide port 114 is formed on the side surface parallel to the side surface 112, and an air guide port similar to the air guide port 115 is formed on the side surface parallel to the side surface 113. Has been.

  As in the first embodiment, the holding housing 110 is rotated about the rotation shaft 120 while the shutter is opened and flash light is supplied. Here, the rotation angle of the holding housing 110 and the spread of the illumination light of each white LED will be described with reference to FIGS. 14 and 15.

  The arrangement pitch when rotating the plurality of white LEDs 80 arranged linearly in one direction as in the second embodiment is 180 °. As described above, in order to uniformly mix the illumination light on the subject surface, the spread of the illumination light on the subject surface is equal to or more than a quarter of the arrangement pitch B “n” of the white LEDs 80, and the arrangement pitch B “n” The movement pitch C may be set to “0 to 0.5n”. Therefore, in order to uniformly mix the irradiation light on the object surface, the illumination light spreads over a quarter or more of the arc that moves to the position of the white LED 80 that is at least 180 ° in the rotation direction. There must be. In addition, if the holding housing 110 is rotated at a predetermined speed so that the rotation angle of the holding housing 110 is 90 ° while the shutter is opened, the illumination light is uniformly mixed on the subject surface. As a result, uneven color temperature and uneven illuminance in illumination light are eliminated.

  As shown in FIGS. 14 and 15, the locus followed by the white LED 80 during rotation of the holding housing 110 becomes larger as the distance from the rotation shaft 120 increases. Therefore, the spread of the illumination light is configured such that the white LED 80 relatively close to the rotation axis 120 is small (see FIG. 14) and the white LED 80 relatively far from the rotation axis 120 is large (see FIG. 15).

  Since the holding casing 110 is formed with an air guide opening, a heat dissipation effect can be obtained by rotating the holding casing 110. In particular, since the side surface 112 and the air guide port provided on the side surface parallel to the side surface 112 intersect the rotation direction when the holding housing 110 rotates, the inflow of outside air is effectively performed, and a higher cooling effect is achieved. Is obtained. Further, by rotating the holding housing 110, the adverse effect on the retina when the subject is a human is avoided as in the first embodiment.

  The first and second embodiments have a configuration in which an air guide port is formed on the side surface of the holding housings 60 and 110 and the white LED 80 is radiated by air flowing from the air guide port according to the rotation of the holding housings 60 and 110. It has, but is not limited to this. FIG. 16 is a diagram illustrating a part of the inside of a rectangular columnar holding housing similar to that of the second embodiment. As shown in FIG. 16, a water cooling jacket 130 is disposed inside the holding housing instead of forming the air inlet. A plurality of recesses 131 are formed in the water cooling jacket 130. Each recess 131 is provided with a drive board 81 of the white LED 80 and a heat conductive sheet 82 that guides heat generated from the drive board 81 to the water cooling jacket 130. Cooling water is injected into the water cooling jacket 130. Heat generated from the drive substrate 81 in response to the driving of the white LED 80 is transmitted to the water cooling jacket 130 via the heat conductive sheet 82 and is radiated by the cooling water in the water cooling jacket 130. Note that the holding housing having such an internal structure is also rotated about the rotation axis in order to eliminate uneven color temperature and uneven illumination and to avoid adverse effects on the retina when the subject is a human being.

  FIG. 17 is a perspective view schematically showing a holding housing 140 to which the third embodiment according to the present invention is applied, and FIG. 18 is a plan view schematically showing a flat surface 141 of the holding housing 140. The holding housing 140 is hollow and has a cylindrical shape, and is fixed to two fixed shafts 150 and 151 provided at the center. On the flat surface 141 of the holding housing 140, six white LEDs 80a, 80b, 80c, 80d, 80e, and 80f are arranged at equal intervals along the circumferential direction. In the third embodiment, the direction along the straight line connecting the white LEDs 80a and 80d is the vertical direction, and the straight line connecting the white LEDs 80b and 80f and the direction along the straight line connecting the white LEDs 80c and 80e are horizontal.

  19 and 20 are diagrams illustrating a driving mechanism of the holding housing 140 according to the third embodiment. 19 is a view shown from the plane 141, and FIG. 20 is a view shown from the direction corresponding to the left direction of FIG. The fixed shafts 150 and 151 are fixed to the coil forming plate 152. The movement restricting plate 160 is formed with an elliptical movement restricting hole 161. The fixed shafts 150 and 151 are inserted through the movement restriction holes 161. The holding housing 140 is fixed to the fixed shafts 150 and 151 on the opposite side of the coil forming plate 152 with the movement restriction plate 160 interposed therebetween. The movement restricting plate 160 is fixedly supported by a predetermined support mechanism (not shown).

  In FIG. 19, drive mechanisms 170 and 180 are provided at the upper end and the right end of the coil forming plate 152, respectively. The drive mechanism 170 includes a flat coil 171, a permanent magnet 172, and a yoke 173 that extend in a direction parallel to the flat surface 141 of the holding housing 140. As shown in FIG. 20, the yoke 173 has a U-shaped cross section, and the flat coil 171 and the permanent magnet 172 are disposed in the concave portion of the yoke 173. Similarly, the drive mechanism 180 includes a flat coil 181, a permanent magnet 182, and a yoke 183 that extend in a direction parallel to the plane 141. The flat coil 181 and the permanent magnet 182 are disposed in a concave portion of a yoke 183 having a U-shaped cross section. The flat coils 171 and 181 are formed near the upper end and the right end of the coil forming plate 152, respectively.

  The permanent magnets 172 and 182 and the yokes 173 and 183 are fixedly supported by a predetermined support mechanism (not shown). Therefore, when a current flows through the flat coil 171, electromagnetic force acts on the coil forming plate 152 in the vertical direction according to the direction of the current, and the coil forming plate 152 is displaced in the vertical direction. When a current flows through the flat coil 181, electromagnetic force acts on the coil forming plate 152 along the horizontal direction according to the direction of the current, and the coil forming plate 152 is displaced in the horizontal direction.

  The fixed shafts 150 and 151 are inserted through the drive restriction holes 161. That is, the drive restriction holes 161 define the vertical and horizontal drive ranges of the coil forming plate 152. In addition, the drive restriction hole 161 stops the coil forming plate 152 at a predetermined position when the flat coils 171 and 181 are not energized.

  By controlling the direction and amount of the current supplied to the flat coils 171 and 181, the coil forming plate 152 is moved along two orthogonal axes. As described above, the fixed shafts 150 and 151 are fixed to the coil forming plate 152, and the holding housing 140 is fixed to the fixed shafts 150 and 151. Accordingly, the holding housing 140 moves along the biaxial direction in accordance with the movement of the coil forming plate 152.

  The vertical movement pitch of the white LEDs for uniformly mixing the illumination light on the subject surface is determined based on the arrangement pitch of the white LEDs 80a and 80d, and the horizontal movement pitch of the white LEDs is the arrangement of the white LEDs 80b and 80f. It is determined based on the pitch and the arrangement pitch of the white LEDs 80c and 80e. The relative relationship between the arrangement pitch and the movement pitch is as described above. That is, when the arrangement pitch of the white LEDs 80a and 80d is “n1”, the movement pitch when vibrating along the vertical direction is “0 to 0.25 (n1)”. Further, when the arrangement pitch of the white LEDs 80b and 80f and the arrangement pitch of the white LEDs 80c and 80e are “n2”, the movement pitch when vibrating along the horizontal direction is “0 to 0.25 (n2)”. By driving the holding housing 140 so that the white LEDs 80a to 80f are vibrated in this way, the emitted light from each white LED is uniformly mixed on the subject surface. As a result, the uneven color temperature and the uneven illuminance caused by the individual differences among the white LEDs are eliminated.

  FIG. 21 is a perspective view schematically showing a holding housing 190 to which the fourth embodiment according to the present invention is applied, and FIG. 22 is a plan view schematically showing a flat surface 191 of the holding housing 190. The holding housing 190 has a quadrangular prism as in the second embodiment. In the holding housing 190, two fixed shafts 192 and 193 are provided in the center in the longitudinal direction of the flat surface 191. The holding housing 190 is fixed to the fixed shafts 192 and 193. On the left and right sides of the fixed shafts 192 and 193, three white LEDs are arranged at equal intervals along the longitudinal direction. The fixed shafts 192 and 193 are fixed to a coil forming plate (not shown) similar to that of the third embodiment. The drive mechanism for the coil forming plate is the same as in the third embodiment. Accordingly, by controlling the current flowing through the flat coil of the drive mechanism, the holding housing 190 is driven along two axial directions that are parallel to the plane 191 and orthogonal to each other. Other configurations are the same as those of the second embodiment.

  In the fourth embodiment, the movement pitch of the white LEDs 80 for uniformly mixing the illumination light on the subject surface is determined by the arrangement pitch between two adjacent white LEDs 80 with the fixed axes 192 and 193 interposed therebetween. That is, assuming that the arrangement pitch of the two white LEDs 80 is “n3”, in order to uniformly mix the illumination light on the subject surface, the holding housing is moved at a moving pitch of “0 to 0.25 (n3)” in the horizontal direction. The body 190 may be vibrated.

  Also in the third and fourth embodiments, similarly to the second embodiment, the heat may be radiated by the water cooling jacket instead of the air inlet.

  The first to fourth embodiments have been described by taking the camera flash device as an example. However, the present invention is not limited to this, and can be applied to an illumination device that is used with other optical devices that require illumination light.

  As described above, according to the present invention, the holding housing that holds the plurality of white LEDs is rotated or moved along two orthogonal axes. Therefore, the uneven color temperature and the uneven illuminance in the illumination light caused by the individual difference of each white LED are eliminated.

1 is a block diagram of a camera to which a first embodiment according to the present invention is applied. It is a perspective view which shows typically the light emission unit of 1st Embodiment. It is a top view which shows typically the holding | maintenance housing | casing of 1st Embodiment. It is a partial cross section figure of a holding housing | casing. It is a block diagram of a flash drive mechanism. It is a flowchart which shows the first half of the process sequence of imaging | photography in 1st Embodiment. 4 is a flowchart illustrating a second half of a photographing procedure in the first embodiment. It is a figure which shows the arrangement | positioning pitch when the breadth of the illumination light of white LED is 11.4 degrees, and the mixing in the to-be-photographed object surface. It is a figure which shows the arrangement pitch when the breadth of the illumination light of white LED is 17.0 degrees, and the mixing in the to-be-photographed object surface. It is a figure which shows the arrangement pitch when the breadth of the illumination light of white LED is 28.0 degrees, and the mixing in the to-be-photographed object surface. It is a figure which shows arrangement | positioning pitch when the breadth of the illumination light of white LED is 22.6 degrees, and mixing in the to-be-photographed object surface. It is a perspective view showing typically a holding case to which a 2nd embodiment concerning the present invention is applied. It is a top view which shows typically the holding | maintenance housing | casing of 2nd Embodiment. It is a figure which shows the relationship between the expansion of the illumination light of white LED located in the approximate center between a rotating shaft and the edge part of a holding | maintenance housing | casing, and the locus | trajectory of rotation. It is a figure which shows the relationship between the breadth of illumination light of white LED near the edge part of a holding | maintenance housing | casing, and the locus | trajectory of rotation. It is a figure which shows the modification of a holding | maintenance housing | casing. It is a perspective view showing typically a holding case to which a 3rd embodiment concerning the present invention is applied. It is a top view which shows typically the holding | maintenance housing | casing of 3rd Embodiment. It is a figure which shows the drive mechanism of a holding | maintenance housing | casing. It is a figure which shows the drive mechanism of a holding | maintenance housing | casing from the left direction of FIG. It is a perspective view showing typically a holding case to which a 4th embodiment concerning the present invention is applied. It is a top view which shows typically the holding | maintenance housing | casing of 4th Embodiment.

Explanation of symbols

10 CPU
22 Flash drive mechanism 60, 110, 140, 190 Holding housing 63, 114, 115 Air guide port 70, 120 Rotating shaft 80 White LED
130 Water cooling jacket 150, 151, 192, 193 Fixed shaft

Claims (16)

A plurality of semiconductor light emitting elements that emit illumination light having a predetermined spread angle ;
A housing for holding the plurality of semiconductor light emitting elements so that the optical axes of the respective outgoing lights are directed in the same direction;
A housing driving means for displacing the housing along a plane intersecting the optical axis,
The housing driving means rotates the housing in one direction around a rotation axis located at the center of the plurality of semiconductor light emitting elements,
When the arrangement pitch in the rotation direction of the plurality of semiconductor light emitting elements is n, the movement pitch when the plurality of semiconductor light emitting elements move while emitting illumination light is greater than 0 and 0.5 n or less. Thus, the illumination device is defined such that the circles of the irradiation regions of the two semiconductor light emitting elements located closest to each other do not intersect with each other, and the circles of the illumination regions on the plane do not intersect with each other .   The lighting device according to claim 1, wherein the plurality of semiconductor light emitting elements are arranged at equal intervals along a circumferential direction on a side surface of the casing parallel to the plane.   The lighting device according to claim 1, wherein the plurality of semiconductor light emitting elements are arranged along a linear direction on a side surface of the housing parallel to the plane.   The housing driving means rotates the housing around an axis extending in a direction orthogonal to the plane at the center of the plurality of semiconductor light emitting elements disposed along the linear direction. Item 4. The lighting device according to Item 3.   The lighting device according to claim 1, further comprising a heat radiating unit that radiates heat generated by the plurality of semiconductor light emitting elements.   The lighting device according to claim 5, wherein the heat dissipating means is an air guide port formed on a side surface intersecting the side surface on which the plurality of semiconductor light emitting elements are disposed in the housing.   The lighting device according to claim 5, wherein the heat dissipating means is a fluid disposed inside the housing. 2. The lighting device according to claim 1, wherein when the number of the semiconductor light-emitting elements is m, θr is determined by the following expression as a rotation angle of the casing which is the moving pitch.
θr = 360 / (2 × m) A plurality of semiconductor light emitting elements that emit illumination light having a predetermined spread angle ;
A housing for holding the plurality of semiconductor light emitting elements so that the optical axes of the respective outgoing lights are directed in the same direction;
A housing driving means for displacing the housing along a plane intersecting the optical axis,
The housing driving means vibrates the housing around a rotation axis located at the center of the plurality of semiconductor light emitting elements,
When the arrangement pitch in the rotation direction of the plurality of semiconductor light emitting elements is n, the movement pitch when the plurality of semiconductor light emitting elements move while emitting illumination light is greater than 0 and equal to or less than 0.25 n. Thus, the illumination device is defined such that the circles of the irradiation regions of the two semiconductor light emitting elements located closest to each other do not intersect with each other, and the circles of the illumination regions on the plane do not intersect with each other .   The lighting device according to claim 9, wherein the plurality of semiconductor light emitting elements are arranged at equal intervals along a circumferential direction on a side surface of the housing parallel to the plane.   The lighting device according to claim 9, wherein the plurality of semiconductor light emitting elements are arranged along a linear direction on a side surface of the housing parallel to the plane.   The housing driving means rotates the housing around an axis extending in a direction orthogonal to the plane at the center of the plurality of semiconductor light emitting elements disposed along the linear direction. Item 12. The lighting device according to Item 11.   The lighting device according to claim 9, further comprising a heat radiating unit that radiates heat generated by the plurality of semiconductor light emitting elements.   The lighting device according to claim 13, wherein the heat dissipating means is an air guide port formed on a side surface intersecting the side surface on which the plurality of semiconductor light emitting elements are disposed in the housing.   The lighting device according to claim 13, wherein the heat dissipating means is a fluid disposed inside the housing. 10. The lighting device according to claim 9, wherein θr is determined by the following expression as a rotation angle of the casing, which is the moving pitch, where m is the number of the semiconductor light emitting elements.
θr = 360 / (4 × m)

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