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`
`US005895128A
`
`United States Patent
`
`[19]
`
`[11] Patent Number:
`
`5,895,128
`
`Kishimoto et al.
`Apr. 20, 1999
`[45] Date of Patent:
`
`[54] ELECTRONIC FLASH AND A CAMERA
`PROVIDED WITH THE SAME
`
`[75]
`
`Inventors: Tsuyoshi Kishimoto. Hannan;
`Masataka Hamada. Osakasayama. both
`of Japan
`
`[73] Assignee: Minolta Co., Ltd.. Osaka. Japan
`
`[21] App]. No.: 09/009,314
`
`[22]
`
`Filed:
`
`Jan. 20, 1998
`
`[30]
`
`Foreign Application Priority Data
`
`Jan. 21. 1997
`
`[JP]
`
`Japan .................................... 9-008985
`
`60313 15/05
`Int. CL“
`{51]
`396/61; 396/182
`. ...........
`[52] US. Cl.
`
`[58] Field of Search ..................................... 396/182. 155.
`396/61, 157, 164. 225; 348/224. 370. 371;
`362/12. 11; 315/241 P
`
`[56]
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`4.847.680
`5.452.049
`5.485.201
`5.815.204
`
`7/1989 Okino ...................................... 348/224
`9/1995 Takagi ............. 396/155
`
`.
`1/1996 Aoki et al.
`348/223
`
`
`..
`...... 348/37]
`9/1998 Abe et al.
`
`Primary Examiner—W. B. Perkey
`Attorney. Agent, or Firm—Burns. Doane. Swecker &
`Mathis. LLP
`
`[57]
`
`ABSTRACT
`
`An electronic flash includes a primary emission unit for
`emitting flash light for illuminating an object. an auxiliary
`emission unit for emitting light having a different color
`temperature from the flash light: and a controller for con-
`trolling emission of the auxiliary emission unit to adjust the
`color temperature of illumination light to the object. This
`electronic flash makes it possible to change the color tem—
`perature of illumination light to an object quickly and easily.
`
`4.485.336
`
`11/1984 Yoshiyama et al.
`
`315/241 P
`
`19 Claims, 18 Drawing Sheets
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`‘
`
`Apr. 20,1999
`
`Sheet 1 of 18
`
`5,895,128
`
`HTC, Exhibit 1017
`
`FI_G.1
`
`l
`
`
`
`W 2
`7
`X (My 3
`
`
`
`
`
` I
`
`
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 2 of 18
`
`5,895,128
`
`FIG. 3
`
`5
`
`503
`
`501
`r—A‘W
`501A 5018
`504 503A 5038
`HE
`
`502
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 3 of 18
`
`5,895,128
`
`FIG. 4
`
`
`
` LIGHTEMISSIONTIMEt(s)
`
`
`
`
`
`OBJECT DISTANCE D(m)
`
`FIG. 5
`
`LIGHT EMISSION TIME”:
`
`\f
`
`BLUE LED
`
` +
`
`COLOR TEMPERATURE
`CORRECTION AT(°K)
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 4 of 18
`
`5,895,128
`
`FIG. 6
`
`LIGHT EMISSION TIME t
`
`BLUE LED
`
`_
`
`0
`
`+
`
`COLOR TEMPERATURE
`CORRECTION AT(°K)
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 5 of 18
`
`5,895,128
`
`m
`
`g
`
`ZQWWEM
`
`
`mmqgomHZOu
`mwEOHUMHMQ
`
`:5ml<~7Eozmz
`
`or
`
`2!oI.
`
`<mmz<upO._.
`
`
`
`........iutzm
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`
`
`
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 6 of 18
`
`5,895,128
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 7 of 18
`
`5,895,128
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 8 of 18
`
`5,895,128
`
`FIG. 10
`
`COLOR TEMPERATUR
`CORRECTION
`
` # 24
`
`FLGRD=1
`FLGBL=1
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 9 of 18
`
`5,895,128
`
`FIG.
`
`11
`
`FLASH
`PHOTOGRAPHING
`
`
`
`# 46
`
`CLOSE SHUTTER
`
`YES
`
`RETURN
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20,1999
`
`Sheet 10 of 18
`
`5,895,128
`
`FIG. 12
`
`LED EMISSION
`START
`
`:50
`3
`
`MONO LIGHT
`EMISSION ?
`
`YES
`
`#56
`
`RED LIGHT
`
`N0
`
`“*5“
`
`EMIT R LED, B LED
`
`EMIT R LED
`
`
`
`
`
`
`#66
`
`EMIT B LED
`
`START COUNTING
`
`RETURN
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20,1999
`
`Sheet 11 of 18
`
`5,895,128
`
`FIG. 13
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 12 of 18
`
`5,895,128
`
`FIG.
`
`15
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 13 of 18
`
`5,895,128
`
`FIG
`
`16
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 14 of 18
`
`5,895,128
`
`FIG. 17
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 15 of 18
`
`5,895,128
`
`mmufiomHZOu
`
`zo_mm_zw
`
`
`
`<Nw>mozmz
`
`<mmz<u2.
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 16 of 18
`
`5,895,128
`
`FIG. 19
`
`FLASH PHOTOGRAPHING
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 17 of 18
`
`5,895,128
`
`
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`US. Patent
`
`Apr. 20, 1999
`
`Sheet 18 of 18
`
`5,895,128
`
`8.0E
`
`$N?KEu:
`/4i1gm/L»m.7£2
`
`C.
`
`omx=2
`
`
`
` m§(\5a:N8.
`
`ohm
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`
`

`

`1
`ELECTRONIC FLASH AND A CAMERA
`PROVIDED WITH THE SAME
`
`1;
`
`2
`FIG. 2 is a rear View of the electronic flash shown in FIG.
`
`5,895,128
`
`This application is based on patent application No.
`9-8985 filed in Japan.
`the contents of which is hereby
`incorporated by reference.
`
`5
`
`BACKGROUND OF THE INVENTION
`
`This invention relates to an electronic flash capable of
`changing the color temperature of flash light for illuminating
`an object and a camera provided with such electronic flash.
`As an electronic flash externally connectable with a
`camera. an electronic flash using a xenon discharge tube is
`generally widely used. A color panel set is known as an
`accessory of this electronic flash. This color panel set
`includes four color panels, e.g.. red. blue. green and yellow.
`and a filter panel for converting the color temperature. By
`suitably combining these panels and mounting them on a
`light emitter of the flash. special color effects in color
`photographing can be obtained and the color temperature of
`the flash can be corrected according to the type of the film.
`With the conventional color panel set. a photographer has
`to suitably combine a color panel and a color temperature
`conversion filter panel and manually mounting them on the
`light emitter of the flash. Accordingly. it is difficult to easily
`change the color temperature of the flash light. Since the
`colors and the color mixing ratio of color panels are
`constant. the color temperature of the flash light cannot be
`continuously adjusted. A certain degree of experience is
`required to obtain a flash light of a desired color. Thus.
`according to the known method for changing the flash light
`by color panels. it is very difficult to quickly change the
`color temperature of the flash light into a desired one by a
`simple operation.
`
`SUMMARY OF THE INVENTION
`
`It is an object of the present invention to provide an
`electronic flash and a flash—provided camera which have
`overcome the problems residing in the prior art.
`According to an aspect of the present
`invention. an
`electronic flash comprises: a primary emission unit which
`emits flash light for illuminating an object: an auxiliary
`emission unit which emits light having a different color
`temperature from the flash light emitted by the primary
`emission unit to the object; and a controller which controls
`emission of the auxiliary emission unit when the primary
`emission unit emits flash light to adjust the color tempera-
`ture of illumination light to the object.
`According to another aspect of the present invention, a
`camera comprises: an electronic flash which emits flash light
`for illuminating an object for photography; an auxiliary
`illumination unit which emits light having a different color
`temperature from the flash light emitted by the electronic
`flash to the object: and a controller which controls emission
`of the auxiliary emission unit when the electronic flash emits
`flash light to adjust the color temperature of illumination
`light to the object.
`These and other objects. features and advantages of the
`present invention will become more apparent upon a reading
`of the following detailed description and accompanying
`drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 3 is a perspective view showing a construction of an
`LED unit:
`
`FIG. 4 is a graph showing a relationship between light
`emission time of LEDs and an object distance;
`FIG. 5 is a graph showing an exemplary relationship
`between light emission time of LEDs and a color tempera—
`ture correction amount of flash light;
`FIG. 6 is a graph showing another exemplary relationship
`between light emission time of LEDs and a color tempera-
`_ ture correction amount of flash light;
`FIG. 7 is a block diagram showing a construction of the
`electronic flash shown in FIG. 1. in particular showing a
`construction concerning emission of flash light and LED
`light;
`FIG. 8 is a diagram showing an external construction of
`a camera provided with the electronic flash shown in FIG. 1.
`FIG. 9 is a schematic diagram showing a combination of
`the electronic flash and the camera;
`FIG. 10 is a flowchart showing a color temperature
`correction processing of the electronic flash shown in FIG.
`1;
`
`FIG. 11 is a flowchart showing a light emission processing
`in flash photographing in the camera shown in FIG. 8;
`FIG. 12 is a flowchart showing a subroutine “LED Emis—
`sion Start” of the flowchart shown in FIG. 11:
`
`FIG. 13 is a front view showing an external configuration
`of a camera provided with an electronic flash capable of
`changing color temperature according to a second embodi-
`ment of the invention;
`
`10
`
`l5
`
`25
`
`30
`
`FIG. 14 is a top plan view of the camera shown in FIG.
`13;
`
`35
`
`FIG. 15 is a front view of a ring electronic flash capable
`of changing color temperature according to a third embodiv
`ment of the invention. this electronic flash being adaptable
`for close-up photographing;
`FIG. 16 is a perspective view showing a schematic
`construction of an LED unit;
`
`FIG. 17 is a chromaticity diagram;
`FIG. 18 is a block diagram showing a construction of the
`ring electronic flash shown in FIG. 15;
`FIG. 19 is a flowchart showing a light emission process-
`ing in flash photographing in use of the ring electronic flash
`shown in FIG. 15;
`FIG. 20 shows a fourth embodiment of the invention. in
`
`particular. diagrammatically showing a basic construction of
`an LED unit for emitting a mixed light of colors R (red). G
`(green). and B (blue); and
`FIG. 21 shows a fifth embodiment of the invention. in
`
`4O
`
`45
`
`50
`
`55
`
`particular, diagrammatically showing a basic construction of
`an LED unit for emitting a mixed light of colors R. G. and
`B.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENTS OF THE
`INVENTION
`
`FIG. 1 is a front View of an electronic flash or a flash light
`emitting device according to a first embodiment of the
`invention: FIG. 2 is a rear view of the electronic flash; and
`FIG. 3 is a perspective view showing a construction of an
`LED unit.
`
`60
`
`65
`
`FIG. 1 is a front view of an electronic flash according to
`a first embodiment of the invention:
`
`The electronic flash 1 is provided at its upper front portion
`with a first light emission window 2. Behind this first light
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`5,895,128
`
`3
`emission window 2 is provided a flash light emitting unit for
`emitting a flash light. The flash light emitting unit serves as
`a primary emission unit. The flash light emitting unit has a
`xenon discharge tube which is a light source of flash light,
`and this xenon discharge tube is movably provided along
`forward and backward directions so that the coverage of
`flash light can be changed. At the first light emission window
`2 is provided a condenser lens 3 constructed by a Fresnel
`lens in order to enhance the illumination efficiency of the
`flash light for illuminating an object located in front.
`Below the first light emission window 2 is provided a
`second light emission window 4 for changing the color
`temperature of the flash light. and a light emitting diode unit
`5 (hereinafter, referred to as “LED unit”) is provided in a
`position behind the second light emission window 4. The
`LED unit 5 serves as an auxiliary emission unit.
`The LED unit 5 is, as shown in FIG. 3. mainly provided
`with a pair of light emitting elements 501 including light
`emitting diodes. an LED drive circuit 502 for driving the
`light emitting elements 501, a diffuser lens 503 and a
`condenser lens 504 which are movable along forward and
`backward directions, a first drive controller 505 for driving
`the diffuser lens 503, a second drive controller 506 for
`driving the condenser lens 504 and a third drive controller
`507 for controlling the driving of the entire unit 5.
`The light emitting elements 501 includes a red LED 501A
`and a blue LED 501B of high luminance which are arranged
`side by side while being spaced apart by a specified interval
`along horizontal direction. Although one each of the red
`LED 501A and the blue LED 501B are provided in this
`embodiment, two or more each of them may be provided.
`Further,
`in place of the LED, a lamp such as a short are
`xenon lamp or a short arc metal halide lamp and a spectral
`filter may be combined to construct such a light emitting
`element.
`
`The diffuser lens 503 is adapted to diffuse a beam of light
`from the light emitting elements 501 and is integrally
`formed with a pair of concave lenses 503A, 503B provided
`in conformity with the red and blue LEDs 501A, 501B. The
`condenser lens 504 is adapted to project a beam of light
`emerging from the diffuser lens 503 toward the object in
`front and is integrally formed with a pair of convex lenses
`504A, 504B provided in conformity with the red and blue
`LEDs 501A. 501B.
`Below the diffuser lens 503 and the condenser lens 504
`
`are provided the first and second drive controllers 505, 506.
`respectively. The first drive controller 505 includes a nut
`portion 505A provided in a specified position of a lens
`support member 503C of the diffuser lens 503. a shaft 505B
`screwed into the nut portion 505A and a motor 505A for
`drivingly rotating the shaft 505B. The shaft 505B is rotated
`by a torque of the motor 505C, thereby linearly moving the
`nut portion 505A along the shaft 505B to move the diffuser
`lens 503 forward and backward. The second drive controller
`
`506 is similarly constructed to the first drive controller 505.
`Specifically. a shaft 5068 is rotated by a torque of a motor
`506C. thereby linearly moving a nut portion 506A along me
`shaft 5068 to move the condenser lens 504 forward and
`backward.
`
`fawning a
`The LED drive circuit 502 is a circuit for
`time during which power is applied to the red and tune LEDs
`501A, 501B. The LED drive circuit 502 is controlled by an
`emission controller to be described later and changes the
`color temperature of light emitted toward the object (flash
`light and light emitted from the LEDs. hereinafter. “illumi—
`nation light”) by controlling the light emission times tRD. tBL
`
`IU
`
`30
`
`40
`
`45
`
`50
`
`60
`
`65
`
`4
`
`of the red and blue LEDs 501A, 5018 according to a
`distance D(meter) to the object.
`Specifically, the light emission time tRD of the red LED
`501A and the light emission time tBL of the blue LED 501B
`are in proportion to the object distance D and have
`characteristics, for example, as shown in FIG. 4. Further, the
`color temperature of the illumination light varies by mixing
`the flash light with the light from the red LED 501A and/or
`from the blue LED 501B. The degree of such a variation can
`be changed, for example, as shown in FIG. 5 according to
`the respective light emission times tRD.
`tBL.
`FIG. 5 shows a variation of a correction amount when the
`
`is corrected
`color temperature of the illumination light
`toward (+)side or (—)side by causing only one LED to emit
`light. FIG. 5 shows that the color temperature of the illu—
`mination light is changed toward (+)side when only the blue
`LED 501B is driven, while it is changed toward (—)side
`when only the red LED 501A is driven.
`The color temperature of the illumination light may be
`changed toward (+)side or (—)side by driving both LEDs
`501A, 501B. For example, when the correction amount is
`small,
`the color temperature may be finely corrected by
`adjusting the mixing ratio of the lights from the red and blue
`LEDs 501A, 501B by driving the red and blue LEDs 501A,
`501B as shown in FIG. 6.
`
`The illumination light for the object can be continuously
`changed to have a desired color temperature by driving
`either one or both of the red and blue LEDs 501A and 501B
`and adjusting the respective light emission times tRD. tm and
`the mixing ratio. For example, the illumination light for the
`object is permitted to have a higher color temperature by
`extending the light emission time tBL of the blue LED 501B
`while being permitted to have a lower color temperature by
`extending the light emission time tRD of the red LED 501A.
`The light emission times tRD, tin of the red and blue LEDs
`501A, 5018 are calculated based on the object distance D
`detected by a camera main body with which the electronic
`flash 1 is connected and a color temperature correction
`amount AT(°K) inputted by a photographer as described
`later. This calculation result is transmitted from the camera
`main body to the electronic flash 1. The LED drive circuit
`502 controls the respective light emission times of the LEDs
`501A, 501B based on the light emission times tRD,
`tBL
`transmitted from the camera main body.
`The third drive controller 507 includes a torque transmis-
`sion mechanism including an unillustrated motor and a gear,
`and is adapted to move the entire LED unit 5 a very small
`distance along horizontal direction (X—direction) and verti—
`cal direction (Y—direction) and change an illuminating direc-
`tion L of the LED unit 5. The LED unit 5 is so provided
`inside the electronic flash 1 as to be movable along X- and
`Y-directions. The third drive controller 507 translates a
`torque of the motor to a movement along a specified
`direction via the torque transmission mechanism to move the
`LED unit 5 a specified distance along the specified direction.
`Referring back to FIG. 1, an auxiliary light emission
`window 6 for the distance metering is provided below the
`second light emission window 4, and an AF auxiliary light
`unit is provided in a position behind this window 6. The AF
`auxiliary light unit has a light emitting element including an
`LED for emitting infrared rays.
`A battery chamber 7 (see FIG. 2) is in an upper portion of
`the electronic flash 1. Below the battery chamber 7 on the
`rear surface of the electronic flash 1 is provided a display 8.
`Further, an operation unit 9 for inputting a variety of pieces
`of information concerning flash firing is provided below the
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`5,895,128
`
`5
`display 8. The display 8 is made of an DCD ( liquid crystal
`display) on which the information inputted from the opera-
`tion unit 9 is displayed. The operation unit 9 is provided with
`a switch group 901 including a plurality of keys. 3 power
`switch 902. an ON/OFF switch 903 for switchingly effecting
`the emission of the LEDs (color temperature correction). a
`test switch 904 for designating a test emission of the LED
`unit 5 and a test switch 905 for designating a test emission
`of the electronic flash 1.
`
`Input modes for a variety of pieces of information includ-
`ing the coverage of the LED unit 5, a correction value of the
`color temperature ATPK). and single color emission/multi—
`color emission are set. and desired data are inputted in the
`respective input modes by operating the switch group 901.
`Further. a connection unit 10 projects from the bottom
`surface of the electronic flash 1 to externally connect the
`electronic flash 1 with the camera. In this connection unit 10
`are provided a plurality ofconnection terminals (not shown)
`for the data communication with the camera main body.
`Although the correction amount of the color temperature
`is directly inputted as numeral value data in this
`embodiment. a correction amount which a photographer
`feels to bring a desired effect may be directly inputted. For
`example.
`a color temperature correction range may be
`divided into :5 stages. and a switch capable of switchingly
`setting the color temperature in stages of —5 to +5 such as an
`exposure correction switch of a camera may be provided as
`a color temperature correction switch so as to set the color
`temperature in stages. Alternatively. there may be provided
`a color temperature correction switch having a color scale
`which enables a photographer to visually confirm a color
`temperature correction amount by feeling. A color tempera-
`ture correction amount can be inputted by changing a
`contact position on the color scale.
`FIG. 7 is a block diagram showing a construction con-
`cerning the emission of the flash light and the light of the
`LED unit 5 of the electronic flash 1. In FIG. 7. members
`identical or similar to those shown in FIGS. 1 to 3 are
`indicated at the same reference numerals.
`
`A flash CPU 11 is a central processing unit for centrally
`controlling the entire operation of the electronic flash 1. An
`emission controller 12 controls the emission of the flash unit
`41 (see FIG. 9). the LED unit 5 and the AF auxiliary light
`unit 42 (see FIG. 9). The emission controller 12 has a
`memory 12A in which the light emission times tRD. ‘31. of the
`red and blue LEDs 501A. 5018 are stored. A circuit block
`13 is a circuitry concerning the light emission of the LEDs
`included in the LED unit 5. A circuit block 14 is a circuitry
`concerning me emission of the flash light of the flash unit 41.
`The LED drive circuit 502 is a series circuit comprised of
`a transistor Tr2 connected in series with the red LED 501A
`and a transistor Tr3 connected in series with the blue LED
`5018. A series circuit comprised of the LED 501 and the
`LED drive circuit 502 is connected in parallel with a power
`battery of the electronic flash 1 set in the battery chamber 7
`via a power switch 902.
`The light emission times I“). tBL of the red and blue LEDs
`501A. 5018 (i.e.. the coverage of the light from the LEDs
`and the color temperature correction amount) are controlled
`by controlling ON-times of the transistors Tr2. Tr3 of the
`LED drive circuit 502. The transistors Tr2. Tr3 are turned on
`and off by the emission controller 12.
`A driver 131 in the circuit block 13 is adapted to drive the
`motors 505C, 506C of the first and second drive controllers
`505. 506. A motor 507C is a drive source of the third drive
`controller 507. and a driver 132 drives this motor 507C. The
`drivers 131. 132 are controllably driven by the emission
`controller 12.
`
`10
`
`15
`
`30
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`6
`The circuit block 14 includes a light emitting circuit 143
`for effecting and stopping the discharge of a xenon discharge
`tube 144 for generating the flash light, a main capacitor CM
`for storing a discharge energy of the xenon discharge tube
`144. a booster circuit 142 comprised of a DC-DC converter
`for charging the main capacitor CM. and a boost control
`circuit 141 comprised of a transistor switching circuit for
`controlling the boosting operation (i.e.. the charging of the
`main capacitor CM) of the booster circuit 142:
`The boost control circuit 141 constitutes a part of an
`inverter circuit
`included in the booster circuit 142. and
`controls the drive (start/stop. boost voltage. etc.) of the
`booster circuit 142 by the ON/OFF control of the transistor
`Tr4. The transistor Tr4 in the boost control circuit 141 is
`controllably turned on and off by the emission controller 12.
`A series circuit constructed by the booster circuit 142 and the
`boost control circuit 141 is connected in parallel with a
`power battery E via a power switch 902. With an output
`terminal of the booster circuit 142 is connected the light
`emitting circuit 143 and the main capacitor CM via a
`rectifying diode D2.
`In flash photographing. a power voltage V02 is boosted to
`a specified charging voltage V32 by the booster circuit 142
`and applied to the main capacitor CM. In this way. electrical
`energy necessary for the flash firing is stored in the main
`capacitor CM.
`The light emitting circuit 143 controls the discharge of the
`electrical energy stored in the main capacitor CM to the
`xenon discharge tube 144. Start and stop timings of the
`discharge of the energy stored in the main capacitor CM are
`controlled by the emission controller 12.
`A projection angle detector circuit 15 detects a set posi—
`tion of the xenon discharge tube 144. A member for moving
`the xenon discharge tube 144 is provided with an encoder for
`the position detection, and the projection angle detector
`circuit 15 detects position information (2-bit signal) of the
`xenon discharge tube 144 from this encoder. This detection
`signal is inputted to the emission controller 12 via the flash
`CPU 11. The emission controller 12 judges an object dis-
`tance (or angle) reachable by the coverage of the flash light
`based on the position information of the xenon discharge
`tube 144. and controllably sets a projection angle of the flash
`light of the flash unit 41 at a specified projection angle
`corresponding to the object distance (or focal length) using
`the judgment result and information on the object distance
`(or focal length) transmitted from the camera connected.
`Information on the projection angle of the flash light
`is
`displayed on the display device 8.
`A diode D1 is adapted to prevent a reverse charging. A
`capacitor C1 is a large capacity capacitor for reducing a fall
`of the drive voltage to the flash CPU 11 by the operation of
`the booster circuit 142.
`
`A circuit 16 comprised of a transistor Trl. an inverter INV
`and a resistor R is a control circuit for stably controlling a
`drive voltage V22 of the emission controller 12. The flash
`CPU 11 outputs an ON/OFF drive signal to the transistor Trl
`via the inverter INV and keeps the drive voltage to be
`supplied to the emission controller 12 at V22.
`FIG. 8 is a diagram of a flash photographing system which
`is assembled by connecting the electronic flash 1 with a
`camera and capable of changing the color temperature of the
`flash light.
`A camera 20 is a single—lens reflex camera. and a con-
`nection unit 21 with which the electronic flash 1 is externally
`connected is provided in the middle of an upper portion of
`the main body of the camera 20. The electronic flash 1 and
`
`HTC, Exhibit 1017
`
`HTC, Exhibit 1017
`
`

`

`5,895,128
`
`7
`the camera 20 are externally connected by coupling the
`connection units 21 and 10. The connection unit 21 is also
`
`provided with a plurality of connection terminals so as to
`correspond to the connection terminals of the connection
`unit 10. By coupling the connection units 10, 21.
`the
`electronic flash 1 and the camera 20 are mechanically and
`electrically connected.
`A taking lens 22 is provided substantially in the middle of
`the front surface of the camera 20. a grip 23 is so formed as
`to project at a left end portion of the front surface. An
`up/down switch 24 for selecting a desired data from a
`plurality of data set in advance in various modes and a
`shutter release button 25 are provided in an upper portion of
`the grip 23. An unillustrated LCD device is provided in a
`position behind the shutter release button 25. On the LCD
`device are displayed a variety of pieces of information
`(including the photographing mode. shutter speed. aperture
`value. continuous/one—shot
`film drive.
`the number of
`exposures. film sensitivity) concerning the photographing of
`the camera.
`
`A main switch 26 is provided in the upper surface of the
`right end of the camera main body. A mode selection switch
`27 is provided in a position before the main switch 26. and
`a function switch 28 is provided adjacent
`to the mode
`selection switch 27. The mode selection switch 27 is a
`switch for selecting the photographing mode such as a
`program mode. a shutter speed priority mode and an aperture
`priority mode. When the up/down switch 24 is operated
`while the mode selection switch 27 is kept pressed.
`the
`photographing mode displayed on the LCD device is cycli-
`cally changed and a desired photographing mode is set by
`displaying it.
`The function switch 28 is a switch for selectively setting
`the shutter speed and the aperture value in the shutter speed
`priority mode and the aperture priority mode and a correc»
`tion value in an exposure correction value setting mode.
`When the up/down switch 24 is operated in a specified mode
`while the function switch 28 is kept pressed. a plurality of
`data such as the shutter speed. aperture value and exposure
`correction value set in advance and to be displayed on the
`LCD device are cyclically changed. and a desired data is
`selectively set by displaying it.
`FIG. 9 is a block construction diagram of the flash
`photographing system including the electronic flash 1 and
`the camera 20. In FIG. 9.
`the same elements as those
`described with reference to FIGS.
`1 to 3. 7 and 8 are
`indicated at the same reference numerals.
`
`In the main body of the camera 20 is provided a camera
`controller 29 (hereinafter. referred to as “CPU 29") con—
`structed by a microcomputer for centrally controlling the
`photographing operation of the camera 20. This CPU 29 can
`communicate with the flash CPU 11 in the electronic flash 1
`via the connection terminals provided in the connection
`units 10. 21.
`The camera 20 includes a mirror assembly 30 which is
`located behind the taking lens 22 and includes a main mirror
`30A and an auxiliary mirror 30B. and a film F is located
`behind the mirror assembly 30. Below the mirror assembly
`30 are provided an AF sensor module 3] for the automatic
`focusing (AF) control and a light meter 32 for the '[TL light
`adjustment. The AFtsensor module 31 detects information
`on a focus position (hereinafter. “AF data”) from an object
`light image introduced thereto via the taking lens 22. the
`main mirror 30A and the auxiliary mirror 308. The light
`meter 32 receives the flash light reflected by a film surface
`and detects an emission stop timing of the flash light using
`
`8
`this light reception data in flash photographing. The AF data
`and the emission stop timing signal are inputted to the CPU
`29.
`
`The CPU 29 calculates a control data for driving a
`focusing lens group 22A of the taking lens 22 from a present
`lens position and to an in—focus position using lens infor—
`mation peculiar to the taking lens 22 which is read from a
`lens ROM provided in the taking lens 22. This control data
`is inputted to a motor control circuit 35 for controlling the
`drive of an AF motor 34 as a driving source of the focusing
`lens group 22A provided in the camera main body.
`A torque of the AF motor 34 is transmitted to a driving
`‘ member 37 of the focusing lens group 22A via an AF coupler
`36. The motor control circuit 35 drives the AF motor 34
`based on the control data to move the focusing lens group
`22A to the in—focus position. thereby automatically focusing
`the taking lens 22.
`the emission stop timing signal is
`On the other hand.
`inputted to the emission controller 12 via the connection
`units 10, 21. The emission controller 12 forcibly stops the
`discharge of the xenon discharge tube 144 in response to the
`emission stop timing signal. thereby controllably adjusting
`the light emission amount of the electronic flash 1 to a
`specified light emission amount.
`Above a viewfinder optical system 38 of the camera 20 is
`provided a light metering circuit 39 for detecting an object
`brightness. The light metering circuit 39 is provided with an
`AB (Automatic Exposure) sensor 391 comprised of light
`receiving elements such as SPCs and an AB optical system
`392 for introducing a reflected light from the object intro-
`duced via the taking lens 22. the main mirror 30A and a
`triangular roof prism 40 further to the AE sensor 391, and is
`adapted to detect the object brightness by receiving the
`reflected light from the object. This object brightness data is
`inputted to the CPU 29 to be used for the judgment as to
`whether or not the electronic flash 1 needs to be fired.
`The flash unit 41 in the electronic flash 1 is, as described
`above, provided with the xenon discharge tube 144 movable
`along forward and backward directions, and the movement
`of the xenon discharge tube 144 is controlled by a driving
`member 411 constructed by a motor and a screw member.
`The AF (Automatic Focus) auxiliary light unit 42 is
`provided with an LED 421 for emitting infrared rays and a
`condenser lens 422. The drive of the first to third drive
`controllers 505 to 507 of the LED unit 5 and the emission of
`the AF auxiliary light unit 42 are controlled in accordance
`with control signals from the emission controller 12.
`In flash photographing, when the shutter release button 25
`is pressed by a half stroke. the AF and AE processings for
`the photographing preparation are performed. In the AF
`processing. the AF data is detected by the AF sensor module
`31 and the AF control is performed based on the AF data to
`obtain a focusing condition of the taking lens 22. Upon the
`completion of the AF control. the motor control circuit 35
`outputs the information on the focusing condition to the
`CPU 29.
`
`This information on the focusing condition is transferred
`via the CPU 29 to the flash CPU 11. which calculates a
`projection direction of the light from the LED unit 5 using
`the received information (i.e.. an object distance
`information) and calculates a control value for the third
`drive