JP2007078823A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera which has a reduced mounting space of a light source and consumes low power. <P>SOLUTION: The camera gas an LED light emitting circuit 10 capable of emitting light in at least two stages of luminance, and AF assisting light radiated when measuring a distance to a measurement object by an auto focus function and a self-timer display light displaying that a self-timer function is being executed are emitted from an LED provided in the LED light emitting circuit 10, and luminance of the AF assisting light and that of the self-timer display light are set independently of each other. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a camera, and more particularly, to a camera that is reduced in size and power consumption.

  Conventionally, in a digital camera, in addition to a strobe device that emits auxiliary light (shooting auxiliary light) to compensate for the lack of brightness of the subject, red-eye reduction light, auxiliary light for assisting focus detection (AF auxiliary light), And a light source for emitting self-timer display light indicating that self-timer photographing is being measured.

  In recent years, digital cameras have been required to be smaller and lighter, and to have a large LCD screen. Therefore, it is becoming difficult to secure a space for mounting these light sources separately.

As conventional techniques for using one light source for two or more applications, there are a “camera” disclosed in Patent Document 1 and a “camera equipped with an active automatic focus detection device” disclosed in Patent Document 2.
JP 2003-140236 A JP-A 63-44639

  The invention disclosed in Patent Document 1 emits photographing auxiliary light, red-eye reduction light, and self-timer display light by a single light emitting means. However, since the light emitting means composed of a plurality of light emitting elements is used, the control becomes complicated. That is, since it is difficult to reduce the size of the control circuit of the light emitting means, it is difficult to reduce the size and weight of the entire digital camera.

  The invention disclosed in Patent Document 2 emits AF auxiliary light and self-timer display light from a single light emitting means. However, the invention disclosed in Patent Document 2 creates self-timer display light by scattering part of the light emitted by the light emitting means. For this reason, when outputting only one of the AF auxiliary light and the self-timer display light, it is necessary to shield one of the unnecessary light. However, scattering or blocking light causes the battery to be wasted and hinders the reduction in power consumption.

  Thus, conventionally, there has not been provided a camera that reduces the mounting space of the light source and achieves low power consumption.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a camera that reduces the mounting space of the light source and achieves low power consumption.

  In order to achieve the above object, the present invention has a light source capable of emitting light with at least two levels of brightness, an AF auxiliary light emitted when measuring a distance to a distance measuring object by an autofocus function, and a self-timer Provided is a camera characterized in that self-timer display light for displaying that a function is being executed is emitted from a light source, and the brightness of AF auxiliary light and the brightness of the self-timer display light are set independently. Is.

  In the above configuration, the light source has a light emitting element and a light emitting circuit that changes the current supplied to the light emitting element in at least two stages, and changes the luminance by changing the current supplied from the light emitting circuit to the light emitting element. In addition, it is more preferable that the light emitting element is an LED.

  In any of the above configurations, a user interface for accepting a user input operation is provided, and at least one of the brightness of the AF auxiliary light and the brightness of the self-timer display light is determined by the input operation performed through the user interface. It is preferably set. Or it has a brightness measuring means for measuring the brightness of the subject, and at least one of the brightness of the AF auxiliary light and the brightness of the self-timer display light is set according to the measurement result of the brightness measuring means. preferable. Here, the brightness of the subject refers to the brightness in the entire imaging region including the object to be focused and the periphery of the focused object.

  In any of the above-described configurations, it is preferable that the digital still camera includes an image sensor and generates image data corresponding to image light from a subject by the image sensor.

  According to the present invention, it is possible to provide a camera that reduces the mounting space of the light source and achieves low power consumption.

A preferred embodiment of the present invention will be described.
FIG. 1 shows a configuration of a digital camera according to the present embodiment. This digital camera is provided with a lens barrel section 7 and a remote control light receiving section 6 on the front. An optical viewfinder 6a, AFLED 8, strobe LED 9, and LCD monitor 110 are disposed on the back of the digital camera. A sub LCD 1 is disposed on the top surface of the digital camera. Furthermore, a memory card / battery cover 2 for protecting a slot for storing a memory card / battery is provided on the side of the digital camera.
The remote control light receiving unit 6 is an interface for receiving a control signal sent from a remote control (not shown). The lens barrel 7 is an optical system for forming image light from a subject on an image sensor.

Further, on the top and back of the digital camera, a release shutter SW1, a mode dial SW2, a zoom switch SW3 (WIDE) and SW4 (TELE), a self-timer / delete switch SW5, a menu switch SW6, an up / strobe switch SW7, and a right switch Various switches such as SW8, display switch SW9, lower / macro switch SW10, left / image confirmation switch SW11, OK switch SW12, and power switch SW13 are arranged.
The release switch SW1 is a button for executing imaging. The mode dial switch SW2 is a switch for switching a photographing mode (Av mode, Tv mode, program mode, manual mode, etc.). The zoom switches SW3 and SW4 are switches for adjusting the angle of view. The self-timer / deletion switch SW5 functions as a switch for selecting whether or not to execute the self-timer function at the time of shooting, but functions as a switch for deleting data of the selected image during image confirmation. . The menu switch SW6 is a switch for selecting the sensitivity of the image sensor and the size and type of image data generated when the image is captured. The strobe switch SW7 is a switch for switching strobe modes (automatic, forced light emission, red-eye reduction, etc.). The right switch SW8 is a switch for moving the cursor to the right on the menu screen or the image selection screen or scrolling the image to the left. The display switch SW9 is a switch for switching on / off the display of the LCD monitor 10. The down / macro switch SW10 functions as a switch for turning on / off the macro shooting mode during shooting, and moves the cursor downward or scrolls the image upward on the menu screen or the image selection screen. Functions as a switch. The OK switch SW12 is a switch for executing a function selected on the menu screen and approving deletion of image data on the deletion screen. The power switch SW13 is a switch for switching on / off the power of the digital camera.

2 and 3 show the functional configuration of the digital camera according to the present embodiment.
The lens barrel 7 includes a zoom optical system 71 including a zoom lens 71a and a zoom drive motor 71b for capturing an optical image of a subject, a focus optical system 72 including a focus lens 72a and a focus drive motor 72b, an aperture 73a and an aperture motor 73b. A diaphragm unit 73, a mechanical shutter 74a and a mechanical shutter motor 74b, and a motor drive 75 for driving each motor.
The motor drive 75 is driven and controlled by a drive command from a CPU block 1043 in the digital still camera processor 104 to be described later, based on an input from the remote control light receiving unit 6 and an operation input from the operation unit key units SW1 to SW13.
The ROM 108 stores a control program written in a code readable by the CPU block 1043 and parameters for control. Note that these parameters may be stored in the internal memory 120. When the power of the digital camera is turned on, the program is loaded into a main memory (not shown), and the CPU block 1043 controls the operation of each part of the apparatus according to the program and temporarily stores data and the like necessary for the control in the RAM 107 and later. The image data is stored in a local SRAM 1044 in the digital still camera processor 104. By applying a rewritable flash ROM as the ROM 108, the control program and control parameters can be changed, and the function can be easily upgraded.

  The CCD 101 is a solid-state imaging device for photoelectrically converting an optical image. The F / E (front end) -IC 102 is a CDS 1021 that performs correlated double sampling for image noise removal, an AGC 1022 that performs gain adjustment, and digital signal conversion. A / D 1023 to be performed, a vertical synchronization signal (VD) and a horizontal synchronization signal (HD) are supplied from the first CCD control unit 1041 and are controlled by the CPU block 1043 and drive timing signals of the F / E-IC 102 TG (Timing Generator) 1024 for generating

  The digital still camera processor 104 performs white balance setting and gamma setting on the output data from the CCD 101 to the F / E-IC 102, and as described above, the first CCD control block 1041 that supplies the VD signal and the HD signal. A second CCD control block 1042 that performs conversion into luminance data and color difference data by filtering processing, a CPU block 1043 that controls the operation of each part of the apparatus, a local SRAM 1044 that temporarily stores data necessary for control, a computer terminal, etc. USB block 1045 for USB communication with other external devices, serial block 1046 for serial communication with external devices such as computer terminals, JPEG CODEC block 1047 for JPEG compression / decompression, interpolation processing of image data size A RESIZE block 1048 that is enlarged or reduced by a TV signal display block 1049 that converts image data into a video signal for display on an external display device such as a liquid crystal monitor or a TV, a memory card that records captured image data, It has a memory card block 10410 for controlling general-purpose PCMCIA and the like.

  The SDRAM 103 temporarily stores image data when the digital still camera processor 104 performs image processing. The stored image data is, for example, “RAW-RGB image data in a state in which white balance setting / gamma setting is performed in the first CCD signal processing block 1041 after being taken in from the CCD 101 via the F / E-IC 102. ”,“ YUV image data ”in which luminance data / color difference data conversion has been performed in the second CCD control block 1042,“ JPEG image data ”compressed in JPEG by the JPEG CODEC block 1047, and the like.

The memory card slot 121 is a slot for inserting a removable memory card or the like. The internal memory 120 is a memory for recording captured image data when no memory card is inserted in the memory card slot 121.
The LCD driver 117 is a drive circuit that drives the LCD monitor 10 to be described later, and also has a function of converting the video signal output from the TV signal display block 1049 into a signal for display on the LCD monitor 10.
The LCD monitor 10 is a monitor for monitoring the state of a subject before photographing, confirming a photographed image, and displaying an image recorded on a memory card or the internal memory 120.
The video AMP 118 is an amplifier for converting the impedance of the video signal output from the TV signal display block 1049 to 75Ω, and the video jack 119 is a terminal for connecting to an external display device such as a TV.
The USB connector 122 is a connector for performing USB connection with an external device such as a computer terminal.
The serial driver circuit 1231 is a circuit for voltage-converting the output signal of the serial block 1046 in order to perform serial communication with an external device such as a computer terminal. The RS-232C connector is serially connected to an external device such as a computer terminal. It is a connector for connection.

The SUB-CPU 109 is a CPU in which ROM and RAM are built in a single chip, and the output signals of the operation key units SW1 to SW13 and the remote control light receiving unit 6 are output to the CPU block 1043 as user operation information, or the CPU block 1043. Is converted into control signals for the sub LCD 1, AF LED 8, strobe LED 9, and buzzer 113, which will be described later, and output.
The sub LCD 1 is a display unit for displaying the number of shootable images. The LCD driver 111 is a drive circuit for driving the sub LCD 1 according to the output signal of the SUB-CPU 109.
The AF LED 8 is an LED for displaying an in-focus state at the time of shooting. The strobe LED 9 is an LED for indicating a strobe charging state. Note that the AF LED 8 and the strobe LED 9 may be used for other display applications such as indicating that the memory card is being accessed.
The operation key units SW1 to SW13 are interfaces for a user to operate. The remote control light receiving unit 6 receives a remote control signal generated from a remote control (not shown) by a user operation.
The audio recording unit 115 includes a microphone 1151 to which a user inputs an audio signal, an amplifier 1152 that amplifies the input audio signal, and an audio recording circuit 1153 that records the amplified audio signal.
The audio reproduction unit 116 includes an audio reproduction circuit 1161 that converts a recorded audio signal into a signal that can be output from the speaker, an audio AMP 1162 that amplifies the converted audio signal, and drives the speaker, and according to the input signal It consists of a speaker that outputs sound.
The LED light emitting circuit 10 includes an LED as a light emitting element and a control IC for changing the luminance of the LED. By controlling the light emitting circuit with the control IC, multi-level luminance control is possible for the LED.

  FIG. 4 shows a configuration example of the LED light emitting circuit 10. One of the N transistors (N is an integer of 2 or more) of the transistors TrA, TrB,..., TrN is driven by a drive signal from the control IC. The resistors Ra, Rb,..., Rn arranged between the transistors and the LEDs all have different resistance values, and are supplied to the LEDs depending on which of the transistors TrA, TrB,. The current that is changed. This makes it possible to change the luminance of the LED in multiple stages depending on which of the transistors TrA, TrB,..., TrN is driven.

  FIG. 5 shows a configuration example of the LED light emitting circuit 10 when an IC having a high drive capability is used. The control IC includes N ports A to N (N is an integer of 2 or more), and each port is connected to the LED via resistors Ra to Rn, respectively. The resistance values of the resistors Ra to Rn are all different values. In this circuit configuration, the LED is directly driven without using a transistor, but the luminance of the LED is changed in multiple stages depending on which of port A to port N is used, as in the configuration shown in FIG. It becomes possible.

6, 7, and 8 show an example of the operation flow of the digital camera according to the present embodiment.
When the self-timer function is executed in the state where the self-timer mode is set in the operation unit 103 or the initial mode (step S101 / Yes), the digital still camera processor 104 turns around with AE information (auto expose) from the CCD 101. Is measured (step S102). Then, the digital still camera processor 104 determines whether or not AF auxiliary light is necessary based on the acquired data from the ROM 108 and the AE information from the CCD 101 (step S103).

  If AF auxiliary light is necessary (step S103 / Yes), the system file processor of the digital still camera processor 104 stores the setting contents (time until photographing) recorded in the internal memory 120 or the ROM 108 and the flashing specification (flashing (Interval) is acquired (step S104). Then, the light-emitting circuit that causes the LED elements of the LED light-emitting circuit 10 to emit light with the brightness adapted to the current state is selected (step S105). Then, a pulse signal adapted to the flashing specification (flashing interval) is generated in the selected light emitting circuit (step S106), a signal is sent to the LED light emitting circuit 10, and the LED element is turned on / off (step S107).

  As the specification of blinking, it is preferable that the blinking interval is shortened as the time until the photographing time is shortened. For example, by increasing the turn-on / off speed every second, the user can recognize the time until shooting.

  If the AF auxiliary light has not been emitted (step S108 / No), the digital still camera processor 104 monitors the emission timing of the AF auxiliary light (step S109). If the light emission timing has not come (step S109 / No), the process returns to step S106, and the digital still camera processor 104 repeats blinking of the LED elements of the LED light emission circuit 10 until the AF auxiliary light emission timing comes.

  When the AF auxiliary light emission timing comes (S109 / Yes), the digital still camera processor 104 changes the light emitting circuit to obtain sufficient luminance as AF auxiliary light (step S110), and then changes the LED to the light emission timing. The LED element of the light emitting circuit 10 is caused to emit light to turn on for AF, and the distance measuring unit 5 acquires AF information (distance information to the subject).

  After that, if the self-timer operation is not finished (step S112 / No), the LED element of the LED light emitting circuit 10 is repeatedly blinked for displaying the self-timer (steps S106, S107, S108 / Yes). If completed (step S112 / Yes), the subject is photographed to generate image data (step S113).

  On the other hand, if AF auxiliary light is not required (step S103 / No), the system file processor of the digital still camera processor 104 stores the setting contents (time until photographing) recorded in the internal memory 120 or the ROM 108 and the blinking specification ( (Blinking interval) is acquired (step S114). Then, the light-emitting circuit that causes the LED elements of the LED light-emitting circuit 10 to emit light with the brightness adapted to the current state is selected (step S115). Then, a pulse signal adapted to the flashing specification (flashing interval) is generated in the selected light emitting circuit (step S116), a signal is sent to the LED light emitting circuit 10, and the LED element is turned on / off (step S117). As the specification of blinking, it is preferable that the blinking interval is shortened as the time until the photographing time is shortened. For example, by increasing the turn-on / off speed every second, the user can recognize the time until shooting.

  After that, if the self-timer operation has not ended (step S118 / No), the LED element of the LED light emitting circuit 10 is repeatedly blinked for displaying the self-timer (steps S116, S117, S118 / Yes). If completed (step S118 / Yes), the subject is photographed to generate image data (step S119).

  On the other hand, when the self-timer function is not used (step S101 / No), the digital still camera processor 104 measures the brightness of the subject based on the AE information from the CCD 101 (step S102). Then, the digital still camera processor 104 determines whether or not AF auxiliary light is necessary based on the acquired data from the internal memory 120 or the ROM 108 and the AE information from the CCD 101 (step S121).

  If AF auxiliary light is necessary (step S121 / Yes), the system file processor of the digital still camera processor 104 records the setting contents (the brightness obtained by AE from the brightness acquired by the AE) from the internal memory 120 or the ROM 108. (Data for selecting which one to use) is acquired (step S122). Then, the light-emitting circuit that causes the LED element of the LED light-emitting element circuit 10 to emit light with the luminance adapted to the current state is selected (step S123). Then, a pulse signal adapted to the flashing specification (flashing interval) is generated in the selected light emitting circuit, the signal is sent to the LED light emitting circuit 10, the LED element is turned on, and the AF information (up to the subject) is detected by the distance measuring unit 5. Distance information) is acquired (step S124). Then, the subject is photographed based on the acquired AF information, and image data is generated (step S125).

  If AF auxiliary light is unnecessary (step S121 / No), the subject is photographed to generate image data (step S126).

In this way, the visibility is improved by turning on the LED with a luminance corresponding to the brightness of the subject. Therefore, when the lighting speed is changed according to the time until photographing, it becomes easier for the subject to check the time until photographing. Further, the power consumption can be reduced by changing the brightness of the self-timer display light and the brightness of the AF auxiliary light according to the brightness of the subject.
In the above operation example, the brightness of the subject is measured by the AE function and the LED is caused to emit light with the brightness corresponding to the brightness. However, the user selects the brightness of the LED using various switches. You may be able to do it. For example, at least one of the operation key units SW <b> 1 to SW <b> 13 may be configured to also serve as a LED brightness selection switch, and the LED brightness may be arbitrarily set according to the operation of the LED brightness selection switch. . When such an LED luminance selection switch is operated, LED luminance information selected and determined by the user is stored in the internal memory 120 or the ROM 108.
When the self-timer mode is set and AF auxiliary light is required (step S103 / Yes), when the brightness selection switch for the LED is operated, when the setting content is acquired in step S104, the user The brightness information of the set LED is acquired simultaneously with the acquisition of the setting contents (time until photographing) and the flashing specification (flashing interval) recorded in the internal memory 120 or the ROM 108, and the LED of the brightness ranging unit 5 is acquired. A light emitting circuit for emitting light from the element is selected (step S105).
When the self-timer mode is set and AF auxiliary light is not required (step S103 / No), when the LED brightness selection switch is operated, it is recorded in the internal memory 120 or the ROM 108 in step S114. Simultaneously with acquisition of the setting contents (time until photographing) and flashing specifications (flashing interval), the LED brightness information set by the user is acquired from the internal memory 120 or the ROM 108, and the LED elements of the LED light emitting circuit 10 are caused to emit light. A light emitting circuit is selected (step A115).
When AF auxiliary light is required (step S121 / Yes) and the LED luminance selection switch is operated, the luminance information set by the user is acquired from the internal memory 120 or the ROM 108 simultaneously with the acquisition of the setting content in step S122. The light emitting circuit that obtains the light and emits the LED element is selected (step S123).
In this way, it is possible to cause the LED to emit light with a luminance according to the user's preference.

In addition, the said embodiment is an example of suitable implementation of this invention, and this invention is not limited to this.
For example, the LED lighting speed, the brightness control method, the circuit configuration, and the like shown in the above embodiment are merely examples, and the present invention is not limited to these.
In the above-described embodiment, a digital camera using an image sensor has been described as an example, but it goes without saying that the present invention is also applicable to a film camera.
As described above, the present invention can be variously modified.

It is a figure which shows the external appearance of the digital camera concerning suitable embodiment of this invention. It is a figure which shows the function structure of the digital camera concerning suitable embodiment of this invention. It is a figure which shows the function structure of the digital camera concerning suitable embodiment of this invention. It is a figure which shows the structural example of a LED light emission circuit. It is a figure which shows another structural example of an LED light emission circuit. It is a flowchart which shows an example of the flow of operation | movement of the digital camera concerning suitable embodiment of this invention. It is a flowchart which shows an example of the flow of operation | movement of the digital camera concerning suitable embodiment of this invention. It is a flowchart which shows an example of the flow of operation | movement of the digital camera concerning suitable embodiment of this invention.

Explanation of symbols

1 Sub LCD
4 Optical viewfinder 5 Ranging unit 6 Remote control light receiving part 7 Lens barrel part 8 AF LED
9 Strobe LED
10 LCD monitor 11
71 Zoom optical system 71a Zoom lens 71b Zoom drive motor 72 Focus optical system 72a Focus lens 72b Focus drive motor 73 Aperture unit 73a Aperture 73b Aperture motor 74 Shutter unit 74a Mechanical shutter 74b Mechanical shutter motor 75 Motor driver 101 CCD
102 F / E-IC
103 SDRAM
104 Digital still camera processor 107 RAM
108 ROM
109 SUB-CPU
111 LCD Driver 113 Buzzer 114 Strobe Circuit 115 Audio Recording Unit 116 Audio Playback Unit 117 LCD Driver 118 Video AMP
119 Video jack 120 Internal memory 121 Memory card slot 122 USB connector 123 Serial driver circuit 1021 CDS
1022 AGC
1023 A / D
1024 TG
1041 First CCD signal processing block 1042 Second CCD signal processing block 1043 CPU block 1044 Local SRAM
1045 USB block 1046 Serial block 1047 JPEG codec block 1048 Resize block 1049 TV signal display block 10410 Memory card controller block 1151 Audio recording circuit 1152 Microphone AMP
1153 Microphone 1161 Audio reproduction circuit 1162 Audio AMP
1163 Speaker 1231 Serial driver circuit 1232 RS-232C connector

Claims (6)

Having a light source capable of emitting at least two levels of brightness;
The AF auxiliary light emitted when measuring the distance to the object to be measured by the autofocus function and the self-timer display light indicating that the self-timer function is being executed are emitted from the light source, and the AF auxiliary light is emitted. A camera characterized in that brightness of light and brightness of the self-timer display light are set independently.   The light source includes a light emitting element and a light emitting circuit that changes a current supplied to the light emitting element in at least two stages, and changes luminance by changing a current supplied from the light emitting circuit to the light emitting element. The camera according to claim 1.   The camera according to claim 2, wherein the light emitting element is an LED.   A user interface for accepting a user input operation is provided, and at least one of the luminance of the AF auxiliary light and the luminance of the self-timer display light is set by an input operation performed through the user interface. The camera according to any one of claims 1 to 3.   Brightness measuring means for measuring the brightness of the subject, and at least one of the brightness of the AF auxiliary light and the brightness of the self-timer display light is set according to the measurement result of the brightness measuring means. The camera according to any one of claims 1 to 4, characterized in that:   The camera according to any one of claims 1 to 5, wherein the camera is a digital still camera that includes an image sensor and generates image data corresponding to image light from a subject by the image sensor.

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