JP4872421B2 - Imaging apparatus, autofocus AF auxiliary light emission method, and program - Google Patents

Description

  The present invention relates to an auto-focus (hereinafter referred to as “AF”) AF auxiliary light emission technology for performing focus detection on a subject with low brightness or low contrast in an imaging apparatus such as a digital camera or a mobile phone with a camera.

Conventionally, there has been a well-known technique of performing AF while projecting AF auxiliary light for AF in order to improve AF accuracy when performing AF. Further, like the technique described in Patent Document 1, there is a technique for adjusting the light balance (light emission pattern) of the flash by providing an LCD filter on the flash. In addition, as in the technique described in Patent Document 2, a plurality of LEDs are provided on the front of the camera, and AF assist light is projected and flash (main light emission) is performed. There was a technology to do flash.
JP 2003-186090 A JP 2003-114462 A

  However, in the technique described in Patent Document 1, the light emission pattern is formed only for flash (main light emission), and is not used as AF auxiliary light for AF. Further, even in the technique described in Patent Document 2, there is no disclosure until the light emission pattern of the AF auxiliary light is made variable.

The present invention has been made to solve the above-described problems, and an imaging apparatus and an autofocus that can capture a more focused image by variably configuring a light emission pattern for irradiating AF auxiliary light. An object is to provide an auxiliary light emission method and program.

In order to solve the above-described problem, in the invention described in claim 1, the light emitting means for emitting AF auxiliary light which is auxiliary light for autofocus, and the light emission pattern of the auxiliary light emitted by the light emitting means are variably configured. A pattern control unit that measures the light reflected from the subject by the auxiliary light emitted from the light emitting unit, and the light emission while changing a plurality of predetermined light emission patterns by the pattern control unit. AF means for emitting auxiliary light by means, and performing autofocus based on a plurality of photometric results of the auxiliary light by the photometric means, AF success / failure judging means for judging success or failure of AF by the AF means, and AF success / failure the determination unit, when the AF is determined to be not established, the set of the plurality of light emitting patterns in a single AF operation by the AF unit Combined to change the, it characterized by having, an AF re-executing means for attempting AF again.

Further, in the invention described in claim 7, a light emitting means for emitting AF auxiliary light, which is auxiliary light for autofocusing, in a plurality of colors, and a light emission pattern and light emission color of the auxiliary light emitted by the light emitting means are variably configured. Pattern control means, photometry means for measuring the light reflected from the subject by the auxiliary light emitted from the light emission means, and light emission patterns and emission color auxiliary light constituted by the pattern control means are emitted by the light emission means. Then, AF is not established by the AF means for performing autofocus from the photometry result of the auxiliary light by the photometry means, the AF success / failure judgment means for judging the success / failure of AF by the AF means, and the AF success / failure judgment means. AF re-execution means that resets the light emission pattern and the light emission color by the pattern control means and tries AF again, Characterized in that it has.

Further, in the invention according to claim 8, wherein the pattern control unit, said plurality of colors provided for each light source provided for each color, you characterized by variably configured patterns for respective light sources .

Further, in the invention according to claim 9, for each execution of AF by the AF device, you and performs AF without changing the pattern by the pattern control unit.

Further, in the invention according to claim 10, for each execution of AF by the AF device, you and performs AF by changing the pattern by the pattern control unit.

In the invention according to claim 11, the AF means performs light emission by the light emitting means and photometry by the photometric means for a plurality of times in one AF, and in one AF by the AF means. wherein the plurality of times of light emission and light measurement, you and performing while changing a pattern by the pattern control unit.

Further, in the inventions according to claims 3 and 13 , the pattern control means controls the transmissive liquid crystal installed on the front surface of the light emitting section, and the light emitting pattern is controlled by controlling the pattern. It shall be the feature.

Further, in the invention according to claim 4 and 14, wherein the pattern control unit, characterized in that for controlling the pattern by the individual ON / OFF of the plurality of LED constituting the light emitting portion.

Further, in the inventions according to claims 2 and 12 , an AF assist is performed by using the storage means for storing the light emission pattern in which AF is achieved and the light emission pattern preferentially stored in the storage means at the next photographing. you and performing light irradiation.
Further, the invention according to claim 15 is characterized in that the light emitting means is configured to emit light for each of the three primary colors of RGB.

Further, in the invention according to claim 5, wherein the light emitting part, you said shared to be used to perform the light emission of the flash and the AF assist light.

Further, in the invention described in claim 6, said AF auxiliary light, the pre-emission performing flash light adjustment, you characterized in that also serves as a.

In the invention according to claim 16 , a light emission step of emitting AF auxiliary light which is auxiliary light for autofocus, a pattern control step of controlling a light emission pattern of auxiliary light emitted by the light emission step, and the light emission step A photometric process for measuring the light reflected from the subject by the auxiliary light emitted by the step, and a plurality of predetermined light emission patterns, the pattern control process changing the pattern, and the auxiliary light is emitted by the light emitting process, and the photometry It is determined that AF is not established by an AF step of performing autofocus from a plurality of photometry results of the auxiliary light in the step, an AF success / failure determination step for determining whether AF is successful in the AF step, and the AF success / failure determination step. If it is, by changing the combination of a plurality of light emitting patterns in a single AF operation by the AF process, the AF again And AF rerun process see, you characterized by having.

In the invention according to claim 17 , the computer has a light emitting function for emitting AF auxiliary light that is auxiliary light for autofocus, a pattern control function for controlling a light emission pattern of auxiliary light emitted by the light emitting function, The auxiliary light emitted by the light emitting function measures the light reflected by the subject, and the auxiliary light is emitted by the light emitting function while changing the pattern of the plurality of predetermined light emitting patterns by the pattern control function. An AF function that performs auto-focusing based on a plurality of metering results of the auxiliary light by the photometry function, an AF success / failure determination function that determines the success or failure of AF by the AF function, and the AF success / failure determination function indicate that AF is not established. If it is determined that, changing the combination of a plurality of light emission patterns in the AF operation once that due to the AF function Te, characterized in that to execute, and the AF re-execution function attempting AF again.

In the invention according to claim 18 , a light emission step of emitting AF auxiliary light, which is auxiliary light for autofocusing, in a plurality of colors, a light emission pattern of the auxiliary light emitted by the light emission step, and a pattern control for controlling the light emission color A photometric step for measuring the light reflected from the subject by the auxiliary light emitted by the light emitting step, and a light emitting pattern and a light emitting color controlled by the pattern controlling step are emitted by the light emitting step, and the photometric When AF is determined to be unsuccessful by the AF step of performing autofocus from the photometry result of the auxiliary light in the step, the AF success / failure determination step for determining the success or failure of AF by the AF step, and the AF success / failure determination step And an AF re-execution step that resets the emission pattern and emission color in the pattern control step and tries AF again. The features.

According to the nineteenth aspect of the present invention, the computer controls the light emission function of emitting AF auxiliary light, which is auxiliary light for autofocus, in a plurality of colors, and the light emission pattern and light emission color of the auxiliary light emitted by the light emission function. A pattern control function, a metering function for measuring the light reflected from the subject by the auxiliary light emitted by the light emitting function, and a light emitting pattern and a light emitting color controlled by the pattern control function are emitted by the light emitting function. An AF function for performing autofocus based on a photometric result of the auxiliary light by the photometry function, an AF success / failure determination function for determining the success / failure of AF by the AF function, and the AF success / failure determination function determine that AF is not established. AF re-execution machine that resets the emission pattern and emission color by the pattern control function and tries AF again When, characterized in that to execute.

  According to the present invention, since the contrast pattern (AF auxiliary light) can be controlled to irradiate the subject, the distance between the subject and the camera is obtained (ranging) based on the contrast by the contrast pattern irradiated during AF, and the focus is more reliably obtained. Detection can be performed.

1A and 1B are diagrams illustrating an appearance of a digital camera that is an example of an imaging apparatus according to the first to third embodiments. FIG. 1A is a front view and FIG. 1B is a rear view.
As shown in FIG. 1A, the digital camera 100 has a strobe light emission window 1 and an imaging lens 2 made of transmissive liquid crystal on the front side. Further, as shown in FIG. 1B, a mode dial 3, a liquid crystal monitor screen 4, a cursor key 6-1, a SET key 6-2, a key 10, and the like are provided on the back of the digital camera 100. Further, a shutter key 8 and a power button 9 are provided on the top surface, and a zoom lever is provided on a side portion of the shutter key (not shown). Further, although not shown in the drawing, a USB terminal connection unit used when connecting to an external device such as a personal computer (hereinafter referred to as a personal computer) or a modem and a USB cable is provided on the side.

In the description of the first to third embodiments, the strobe light emission window 1 is described as being made of transmissive liquid crystal. However, the present invention is not limited to this. For example, the strobe light emission window 1 is assumed to be made of a transparent member, and the strobe light emission window 1 A liquid crystal surface in a state of being very close to the front surface or the back surface of 1 may be provided. In the following description, “liquid crystal of strobe light emission window 1” or “strobe light emission window liquid crystal” includes a liquid crystal surface provided very close to the front or back surface of strobe light emission window 1.
In addition, the light emission pattern of the auxiliary light may not be changed by a pattern changing device installed on the front surface of the light emitting unit that emits auxiliary light. The light emitting unit itself may be a plurality of small light emitting units (for example, a plurality of LEDs). The light emission pattern may be formed by forming and turning on / off the small light emitting portion.

  FIG. 2 is a diagram illustrating an example of an electronic circuit configuration of the digital camera according to the first and second embodiments illustrated in FIG. 1. In FIG. 2, the digital camera 100 is focused by moving the zoom lens 11-1 and the focus lens 12-2 for moving the zoom lens 12-1 and performing the optical zoom operation in the photographing mode which is the basic mode. An AF driving unit 11-2 that performs the operation, a lens optical system 12 that constitutes the imaging lens 2 including the zoom lens 12-1 and the focus lens 12-2, a CCD 13 that is an imaging device, a timing generator (TG) 14, and a vertical Driver 15, sample hold circuit (S / H) 16, A / D converter 17, color process circuit 18, DMA (Direct Memory Access) controller 19, DRAM interface (I / F) 20, DRAM 21, control unit 22, VRAM Controller 23, VRAM 24, digital video encoder 25, display unit 26, JPEG times 27, storage memory 28, a key input unit 30, a strobe drive unit 31, and a flash emitter 32 and a flash emitter window LCD driver 33,.

  In the monitoring state in the photographing mode, the zoom driving unit 11-1 drives a zoom lens driving motor (not shown) to move the zoom lens 12-1 when there is an optical zoom instruction. The AF drive unit 11-2 drives a focus lens drive motor (not shown) to move the focus lens 12-2. A CCD 13, which is an image pickup device disposed behind the photographing optical axis of the lens optical system 12 constituting the image pickup lens 2, is scanned and driven by a timing generator (TG) 14 and a vertical driver 15, and images are formed at regular intervals. A photoelectric conversion output corresponding to the optical image is output for one screen.

  The CCD 13 is a solid-state imaging device that captures a two-dimensional image of a subject, and typically captures an image of several tens of frames per second. The imaging element is not limited to a CCD, and may be a solid-state imaging device such as a CMOS (Complementary Metal Oxide Semiconductor).

  The photoelectric conversion output is appropriately gain-adjusted for each primary color component of RGB in the state of an analog value signal, sampled and held by a sample hold circuit (S / H) 16, and digital data by an A / D converter 17. Color process processing including image interpolation processing and γ correction processing is performed in the color processing circuit 18 to generate a luminance signal Y and color difference signals Cb and Cr, and the DMA (Direct Memory Access). ) Is output to the controller 19.

  The DMA controller 19 uses the luminance signal Y and the color difference signals Cb and Cr output from the color process circuit 18 by using the composite synchronization signal, the memory write enable signal, and the clock signal from the color process circuit 18 as well as a DRAM interface. DMA transfer is performed via the (I / F) 20 to the DRAM 21 used as a buffer memory.

  The control unit 22 controls the overall control operation of the digital camera 100, and an operation program executed by the CPU or MPU (hereinafter referred to as CPU) and the CPU including operation control in the simple photographing mode as will be described later. A program storage memory such as a flash memory, and a RAM used as a work memory. After the DMA transfer of the luminance and chrominance signals to the DRAM 21, the luminance and chrominance signals are transmitted via the DRAM interface 20. Reading from the DRAM 21 and writing to the VRAM 24 via the VRAM controller 23.

  The control unit 22 also extracts a processing program and menu data corresponding to each mode stored in a program storage memory such as a flash memory in response to the status signal from the key input unit 30, and In addition to the execution control of other functions, for example, the autofocus auxiliary light emission control operation based on the present invention, the zoom operation in the movement range of the zoom lens corresponding to the set shooting mode (hereinafter referred to as the zoom region), Digital zoom processing by digital zoom instruction, through display, automatic focusing, shooting, recording, execution control such as playback / display of recorded image, function selection menu display control at function selection, setting screen display control, etc. Do.

  The digital video encoder 25 periodically reads the luminance and color difference signals from the VRAM 24 via the VRAM controller 23, generates a video signal based on these data, and outputs the video signal to the display unit 26.

  As described above, the display unit 26 functions as a monitor display unit (electronic finder) in the shooting mode. By performing display based on the video signal from the digital video encoder 25, the display unit 26 receives from the VRAM controller 23 at that time. An image based on the stored image information is displayed on the liquid crystal monitor screen 4 in real time. Also, a multi AF frame can be displayed during multi AF.

  In response to the focus instruction, the control unit 22 immediately stops the path from the CCD 13 to the DRAM 21 after the DMA transfer of the luminance and chrominance signals for one screen captured from the CCD 13 to the DRAM 21 at that time, and performs recording. Transition to saved state.

  In this stored recording state, the control unit 22 transmits the luminance and color difference signals for one frame written in the DRAM 21 through the DRAM interface 20 to each of Y, Cb, and Cr components of 8 pixels × 8 pixels horizontally. Are read out in units called basic blocks and written in a JPEG (Joint Photograph Cording Experts Group) circuit 27. The JPEG circuit 27 uses ADCT (Adaptive Discrete Cosine Transform) and a Huffman code which is an entropy coding system. Data compression is performed by processing such as conversion. The obtained code data is read out from the JPEG circuit 27 as a data file of one image, and is recorded and stored in the storage memory 28. In addition, the controller 22 activates the path from the CCD 13 to the DRAM 21 again with the completion of the compression processing of the luminance and color difference signals for one frame and the writing of all the compressed data to the storage memory 28.

  In the playback mode, which is the basic mode, the control unit 22 selectively reads out the image data recorded in the storage memory 28, and is compressed by a procedure completely opposite to the procedure of data compression in the image shooting mode by the JPEG circuit 27. The expanded image data is decompressed, the decompressed image data is expanded and stored in the VRAM 24 via the VRAM controller 23, and then periodically read out from the VRAM 24 to generate a video signal based on the image data. The display unit 26 reproduces and outputs.

  The JPEG circuit 27 supports a plurality of compression ratios, and a mode for storing data corresponding to the compression ratio includes a mode corresponding to a high resolution (generally called high definition, fine, normal, etc.) with a low compression ratio. There is a low-resolution (commonly called economy) mode with a high compression rate. It also supports high to low pixel counts.

  The storage memory 28 includes a recording medium such as a built-in memory (flash memory), a hard disk, or a removable memory card, and stores and records image data, shooting information, and the like.

  The key input unit 30 includes the mode dial 3, the cursor key 6-1, the SET key 6-2, the shutter key 8, the power button 9, the key 10 used for the playback instruction operation, the zoom lever (not shown), and the like. The signals accompanying these key operations are sent directly to the control unit 22.

  The mode dial 3 is used to select a shooting mode and a playback mode. The user can select various shooting modes by operating the mode dial 3.

  The cursor key 6-1 is a key operated when pointing (designating) a menu or icon displayed on the LCD monitor screen 4 with a cursor when setting a mode or selecting a menu. Alternatively, it can be moved left and right. A SET key 6-2 is a key that is pressed when the item displayed by the cursor by the cursor key 6-1 is selected or set or confirmed.

  The shutter key 8 performs a release operation at the time of shooting, has a stroke of two steps, and performs auto focus (AF) and automatic exposure (AE) by the first step operation (half-pressed state). In-focus instruction signal is generated and a shooting instruction signal for performing shooting processing is generated by the second-stage operation (fully pressed state). In the inventions according to the first to third embodiments, the shutter key is used during flash photography. The pre-flash and AF auxiliary light emission of the strobe is performed only by the full-pressing operation of No. 8, AF and AE are performed, and the main flash of the strobe is emitted immediately after the focusing is completed to take a picture.

  The strobe drive unit 31 controls the timing of the pre-flash and the main flash of the strobe light-emitting unit 32 under the charge control for the strobe light-emitting unit 32 and the control of the control unit 22.

The strobe light emission window liquid crystal driving unit 33 drives the liquid crystal in the strobe light emission window 1 under the control of the control unit 22 to form a predetermined contrast pattern when the strobe light emission unit 32 performs pre-light emission.
As a result, when the strobe light emitting unit 32 pre-lights, the subject is irradiated with the contrast pattern formed in the strobe light emission window 1.

  FIG. 3 is an explanatory diagram of the autofocus auxiliary light emission method according to the present embodiment. In FIG. 3, reference numeral 100 denotes a digital camera, reference numeral 1 denotes a stroboscopic light emitting window made of a transmissive liquid crystal, reference numeral 101 denotes a contrast pattern irradiated to the subject as AF auxiliary light through the stroboscopic light emitting window 1, and reference numeral 102 denotes stroboscopic light emission. Indicates the flash light of the hour.

  In this embodiment, a transmissive liquid crystal is used for the portion of the strobe light emission window 1 that transmits strobe light, and AF (autofocus) is easily performed during strobe pre-emission as shown in FIGS. 3 (a) to 3 (c). Thus, after the contrast pattern 101 is projected on the strobe light emission window 1, the small-scale light emission (pre-light emission) is intermittently used as AF auxiliary light, and the subject is irradiated with the contrast pattern reflected on the strobe light emission window 1, and thereafter At the time of the main flash emission, as shown in FIG. 3D, the contrast pattern displayed on the flash emission window 1 is erased, and the flash is emitted so as to completely transmit the flash light.

  FIG. 4 is a flowchart showing a schematic operation example of the digital camera 100 according to the present embodiment at the time of flash photography, and this flowchart realizes the autofocus assist function (steps S5 to S7 below) of the present invention in the computer of the digital camera 100. It is for explaining the program for making it happen. The following processing will be basically described by an example in which the control unit 22 executes according to a program stored in advance in a program storage memory such as a flash memory, but it is not necessary to store all functions in the program storage memory. Accordingly, a part or all of the information may be received via a network. Hereinafter, description will be given based on FIGS.

  When the photographing mode is selected when the power is turned on, the control unit 22 performs initial setting of photographing conditions and the like (step S1), and executes the AE process for the through image with the focal length corresponding to the zoom value at that time, and the color process. The circuit 18 obtains image data from the CCD 13 and performs white balance (AWB) processing, and then starts DMA transfer to the DRAM 21 via the DMA controller 19 and the DRAM interface (I / F) 20. The through image is displayed on the liquid crystal monitor screen 4 of the display unit 26 by rewriting the video through image data obtained by thinning out the image data. Although not shown, the zoom lens 12-1 is moved to a designated position by performing zoom processing with an instruction based on a zoom operation (step S2).

  The control unit 22 obtains the luminance of the subject from the luminance signal from the color process circuit 18 and compares it with a predetermined value to check whether or not strobe light emission is necessary. If strobe light emission is necessary, the process proceeds to step S4. The process proceeds to a normal photographing process (not shown) (step S3).

  The control unit 22 checks whether or not the shutter key 8 has been fully pressed based on a signal from the key input unit 30. If there is a full press operation, the control unit 22 proceeds to step S5, and if not, returns to step S2 ( Step S4).

  The control unit 22 starts the AF operation (step S4), and performs the emission pattern setting, the AF auxiliary light emission control, and the dimming control as shown in FIGS. 5 to 8 and 11 to 14 (step S6). ), Obtaining the distance between the subject and the camera (ranging) based on the contrast pattern (AF auxiliary light) irradiated to the subject by the strobe pre-flash, and performing focus detection (that is, performing AF) and focusing Then, AE processing and automatic white balance (AWB) processing for main shooting based on through image data captured when the shutter key 8 is fully pressed is performed (step S7). For example, if the AF process has a contrast detection method, the contrast (high frequency component) of the subject is detected while moving the focus lens 12-2 included in the lens optical system 12 in the optical axis direction. A process for determining a position where the contrast increases is performed. During this time, the VRAM 24 is rewritten with through image data obtained by thinning out the image data from the CCD 13 until the AF processing is completed, and a through image is displayed on the liquid crystal monitor screen 4 of the display unit 26. Details of the setting of the light emission pattern and the control of light emission of the AF auxiliary light in step S6 will be described in the description of the first to third embodiments and their modifications described later.

  Next, when the AF process or the like is completed, the control unit 22 sends a control signal based on the dimming result to the strobe light emission window liquid crystal drive unit 33 to cause the strobe light emission unit 32 to emit main light (step S8). The path from the camera to the DRAM 21 is stopped to switch to the CCD driving system at the time of main photographing different from that at the time of through image acquisition, and image compression processing is performed on the captured image data. The image file) is recorded in the storage memory 28, and the image capturing for one frame is completed (step S9).

  With the operation shown in the flowchart of FIG. 4, the digital camera 100 can use the strobe pre-flash not only for dimming but also as AF auxiliary light. At that time, since the subject is irradiated with the contrast pattern reflected in the strobe light emission window 1, focus detection can be performed with the strobe pre-emission even for a subject with low contrast even without a projection LED.

  Furthermore, when pre-flash is used to control the amount of light emitted when the flash is fired, a pattern is projected on the liquid crystal in the flash light emission window 1 to make it easier to obtain contrast for AF, and not only flash light control but also AF operation is performed. In this flash photography, the procedure of “half-pressing the shutter; AF operation with AF auxiliary light” → “full-pressing the shutter; dimming with flash emission” → “shooting” has been changed according to the present invention. Push; AF & light control by flash emission → “shooting”, so that the flash shooting can be performed with a single shutter operation, so the time lag until shooting can be shortened. In addition, since light adjustment is also performed by AF auxiliary light by strobe pre-light emission, power consumption due to strobe light emission can be suppressed as compared to when AF auxiliary light emission and light adjustment pre-issue are separately performed.

  In addition, since the conventional AF auxiliary light is pinpoint like LED projection, the effect is not good except for the spot AF at the center of the subject. However, according to the present invention, the AF is used with a wide field angle by using the strobe pre-flash. Since the auxiliary light can be irradiated, there is a significant effect even when the position is designated by multi-AF or a spot.

In the flowchart of FIG. 4, the shutter key 8 is fully pressed in step S4, so that the flash photography is performed with a single shutter operation, such as “AF & light control by flash emission” → “shooting”. However, in step S4, the shutter key 8 is pressed halfway to perform “AF & light control by flash emission”, and then the shutter key 8 is fully pressed to issue a shooting instruction. You may comprise so that "pre-light emission" may be performed and "main light emission" may be performed after that. In the case of such a configuration, the use of an LED instead of a light emitting discharge tube as a strobe makes it possible to smoothly perform AF & dimming by strobe light emission and pre-light emission by strobe light emission. As a result, it is possible to take a picture after the photographer confirms whether or not the AF state is appropriate, so that the AF can take a more appropriate picture.
In the above example, the flash and the AF auxiliary light are configured to emit light from the same light emitting unit. However, this is not necessary, and the flash light emitting unit and the AF auxiliary light emitting unit are separated. May be installed. By allowing such a configuration, the degree of freedom in design is improved.
Further, the pre-flash for dimming the flash and the AF auxiliary light are used together, but they may be performed separately. By allowing such a configuration, the degree of freedom in design is also improved.
Further, the light emission pattern when AF is completed may be stored in, for example, the storage memory 28, and the next time AF is executed, the light emission pattern for which AF has succeeded may be preferentially used. In addition to storing the light emission pattern that AF succeeded last time, the pattern that AF succeeded is memorized over time and used in preference to the light emission pattern that has the highest success in memory. You may comprise so that AF may be performed. With this configuration, it is possible to perform AF more quickly and more reliably.

(Embodiment 1)
FIG. 5 is a flowchart showing the light emission pattern setting and AF auxiliary light emission control operation of the digital camera according to the present embodiment, and corresponds to a detailed flowchart (AF auxiliary light emission control means) of step S6 in the flowchart of FIG. .

  In FIG. 5, when the shutter key 8 is fully pressed in step S4 of FIG. 4, the control unit 22 takes out pre-light emission pattern data stored in a memory such as a ROM and drives the strobe light emission window liquid crystal together with the control signal. The transmissive liquid crystal of the strobe light emission window 1 is driven to display the contrast pattern on the strobe light emission window 1 (step S6-1), and a drive control signal is sent to the strobe drive part 31 to send the strobe light emission part. 32 is emitted at a predetermined time interval with a predetermined amount of light, the subject is irradiated with a contrast pattern displayed in the strobe light emission window 1, the amount of light of the subject is detected from the luminance signal from the color process circuit 18, and the detected value is used as a basis. The flash is dimmed (step S6-2).

  Next, the control unit 22 checks whether or not the AF auxiliary light is emitted a predetermined number of times (for example, three times). If the predetermined number of times, the process proceeds to step S6-4. The process returns to step S6-2 (step S6-3).

  When the AF auxiliary light is emitted a predetermined number of times, the control unit 22 sends a control signal to the strobe light emission window liquid crystal drive unit 33 to erase the contrast pattern displayed on the strobe light emission window 1 and proceeds to step S7. (Step S6-4).

  Specifically, for example, assuming that the contrast pattern is “A” and is repeated three times, “A”, “A”, and “A” are repeated three times and AF assist light with the pattern “A” is irradiated. After step S6-4, focusing is performed in step 7.

With the operation shown in the flowchart of FIG. 5, the digital camera 100 repeatedly irradiates the subject with the same contrast pattern (AF auxiliary light) a predetermined number of times by simply pressing the shutter key 8 completely. The camera distance can be obtained (ranging), focus detection can be performed, the focus can be adjusted, and the flash can be adjusted.
<Modification>
In the above embodiment, AF auxiliary light having the same contrast pattern is emitted a predetermined number of times, but AF auxiliary light having different contrast patterns may be emitted sequentially.
FIG. 6 is a flowchart showing the setting of the light emission pattern of the digital camera and the light emission control operation of the AF auxiliary light based on this modification. In the example of FIG. 6, it is assumed that a predetermined number (for example, 3 patterns) of pre-light emission pattern data of different patterns is stored in a memory such as a ROM.

  In FIG. 6, when the shutter key 8 is fully pressed in step S4 of FIG. 4, the control unit 22 sends the pre-light emission pattern data extracted from the memory such as the ROM to the strobe light emission window liquid crystal drive unit 33 together with the control signal. Then, the transmissive liquid crystal of the strobe light emission window 1 is driven to display a contrast pattern on the strobe light emission window 1 (step S6-1), and further, a drive control signal is sent to the strobe drive part 31 to set the strobe light emission part 32 to a predetermined value. The subject is irradiated with a contrast pattern displayed on the strobe light emission window 1 at a predetermined time interval, and the amount of light of the subject is detected from the luminance signal from the color process circuit 18, and the strobe light is detected based on the detected value. Dimming is performed (step S6-2).

  Next, the control unit 22 checks whether or not there is a change pattern (pre-flash pattern data) to be set / displayed next on the flash light emission window 1 in a memory such as a ROM. If there is, the process proceeds to step S6-5. If the change pattern is over, the process proceeds to step S6-4 (step S6-3).

  When the change pattern is finished, the control unit 22 sends a control signal to the strobe light emission window liquid crystal drive unit 33 to erase the contrast pattern displayed on the strobe light emission window 1, and proceeds to step S7 (step S6-4). ).

  If the change pattern (pre-light emission pattern data) is still in the memory such as the ROM, the next pattern (pre-light emission pattern data) stored in the memory such as the ROM is set as the contrast pattern, and the process proceeds to step S6-1. Return (step S6-5).

  Specifically, for example, if there are three contrast patterns “A”, “B”, and “C”, the patterns “A”, “B”, and “C” in the order of “A”, “B”, and “C”. After focusing the AF auxiliary light by "", the focus is achieved in step 7 through step S6-4.

  With the operation shown in the flowchart of FIG. 6 described above, the digital camera 100 sequentially irradiates the subject with different contrast patterns (AF auxiliary light) one by one by simply pressing the shutter key 8 to obtain the distance between the subject and the camera ( Ranging) to detect the focus, focus and adjust the flash. Therefore, even when the contrast pattern is not suitable for performing AF, since AF is performed while changing the contrast pattern, AF can be performed without any problem.

(Embodiment 2)
In the first embodiment, AF auxiliary light having the same contrast pattern is emitted a predetermined number of times, and in the modified example, AF auxiliary light having different contrast patterns is emitted cyclically. However, the contrast pattern irradiated to the subject is AF. The AF auxiliary light pattern may be switched depending on whether it is appropriate for use.

  FIG. 7 is a flowchart showing the light emission pattern setting and AF auxiliary light emission control operation of the digital camera based on the present embodiment. In the example of FIG. 7, it is assumed that a predetermined number (for example, three patterns) of pre-light emission pattern data of different patterns is stored in a memory such as a ROM, and that nine patterns are stored in the example of FIG. To do.

  In FIG. 7, when the shutter key 8 is fully pressed in step S4 of FIG. 4, the control unit 22 takes out pre-light emission pattern data stored in a memory such as a ROM and drives the strobe light emission window liquid crystal together with the control signal. The transmissive liquid crystal of the strobe light emission window 1 is driven to display the contrast pattern on the strobe light emission window 1 (step S6-1), and a drive control signal is sent to the strobe drive part 31 to send the strobe light emission part. 32 is emitted at a predetermined time interval with a predetermined amount of light, the subject is irradiated with a contrast pattern displayed in the strobe light emission window 1, the amount of light of the subject is detected from the luminance signal from the color process circuit 18, and the detected value is used as a basis. The flash is dimmed (step S6-2).

  Next, the control unit 22 checks whether or not the AF auxiliary light is emitted a predetermined number of times (for example, three times). If the predetermined number of times, the process proceeds to step S6-4. The process returns to step S6-2 (step S6-3).

  When the AF auxiliary light is emitted a predetermined number of times, the control unit 22 determines whether or not the contrast pattern irradiated to the subject is appropriate for AF. If appropriate, the process proceeds to step S6-5, otherwise. In this case, the process proceeds to step S6-6 (step S6-4). Whether or not the contrast pattern irradiated to the subject is appropriate for AF can be determined, for example, based on whether or not the contrast data (high-frequency component) obtained from the subject irradiated with the contrast pattern is appropriate for AF.

  If the contrast pattern is suitable for AF, the control unit 22 sends a control signal to the strobe light emission window liquid crystal drive unit 33 to erase the contrast pattern displayed on the strobe light emission window 1 and proceeds to step S7 ( Step S6-5).

If the contrast pattern is not appropriate for AF, the control unit 22 sets the next pattern (pre-light emission pattern data) stored in a memory such as a ROM as the contrast pattern, and returns to step S6-1. Step S6-6).

  Specifically, for example, if there are three contrast patterns “A”, “B”, and “C” and the same pattern is repeated three times, “A”, “A”, and “A” are repeated three times. After repeatedly irradiating AF auxiliary light with the pattern “A”, it is determined whether or not the pattern “A” is appropriate for AF. If not, “B”, “B”, and “B” are performed three times. After repeatedly irradiating AF auxiliary light with the pattern “B”, it is determined whether or not the pattern “B” is appropriate for AF. If not, “C”, “C”, and “C” are repeated three times. After repeatedly irradiating the AF auxiliary light with the pattern “C”, the operation of determining whether the pattern “C” is appropriate for AF is cyclically repeated, and when the appropriate pattern for AF is irradiated, step Focus on step 7 after S6-5 The Rukoto.

  With the operation shown in the flowchart of FIG. 7, the digital camera 100 repeatedly irradiates the subject with the same contrast pattern (AF auxiliary light) a predetermined number of times only by fully pressing the shutter key 8, but the contrast pattern is suitable for AF. If not, the operation of repeating the irradiation of the next contrast pattern a predetermined number of times is repeated, so that even if one pattern is inappropriate for AF, another pattern can be focused.

<Modification>
In the first embodiment, the AF assist light having the same contrast pattern is emitted a predetermined number of times, and the pattern of the AF assist light is switched depending on whether or not the contrast pattern irradiated to the subject is appropriate for AF. The AF auxiliary light pattern may be switched depending on whether or not the contrast pattern irradiated to the subject by cyclically emitting the pattern AF auxiliary light is suitable for AF.

FIG. 8 is an explanatory diagram of the setting of the light emission pattern of the digital camera and the light emission control operation of the AF auxiliary light according to this modification. For the sake of explanation, it is assumed that the contrast patterns are nine patterns “1” to “9”.
In FIG. 8, when the shutter key 8 is fully pressed in step S4 of FIG. 4, pre-light emission pattern data “1” to “3” stored in a memory such as a ROM are sequentially extracted in step S6-1. The control signal is sent to the strobe light emission window liquid crystal drive unit 33 to drive the transmissive liquid crystal of the strobe light emission window 1 to display the contrast patterns “1” to “3” on the strobe light emission window 1 in order, and then to the patterns “1” to “1”. After irradiating AF auxiliary light by “3”, it is determined whether or not the patterns “1” to “3” are appropriate for AF. If not, the same operation is performed in step S6-2 by “4” to “4”. After irradiating AF auxiliary light by “6”, it is determined whether or not the patterns “4” to “6” are appropriate for AF. If they are not appropriate, the pattern “7” to “7” by the same operation in step S6-3. To “9” That after the irradiation with the AF assist light, the pattern "7" to "9", it is determined whether proper for the AF, if not appropriate to repeat the operation returns to step S6-1. Also, when any of the AF auxiliary light according to the patterns “1” to “3”, the AF auxiliary light according to the patterns “4” to “6”, and the AF auxiliary light according to the patterns “7” to “9” is appropriate for AF Advances to step S7.

  When the digital camera 100 sequentially irradiates the subject with different contrast patterns (AF auxiliary light) just by pressing the shutter key 8 fully by the operation shown in the flowchart of FIG. 8 above, but the contrast pattern is not suitable for AF. Since the operation of irradiating the next contrast pattern is repeated cyclically, even if one pattern is inappropriate for AF, it can be focused with another pattern.

(Embodiment 3)
FIG. 9 is a diagram illustrating an example of the electronic circuit configuration of the digital cameras 120 and 130 that are examples of the imaging apparatus according to the third to fifth embodiments. The external appearance of the digital cameras 120 and 130 includes a plurality of light emitting LEDs arranged in front of the digital camera shown in FIG. 1 (see FIGS. 10 and 16).

In FIG. 9, the electronic circuit configuration of the digital camera 120 (or 130) is the electronic circuit configuration of the digital camera shown in FIG. The functions and configurations of the other components (lens optical system 12 to strobe light emitting unit 32) are the same as those in FIG.
When the shutter key 8 is half-pressed, the multi-emission control unit 34 causes a plurality of light emitting LEDs (multi-LEDs) provided on the front side of the digital camera 120 to emit light simultaneously or in a predetermined order, and AF auxiliary light The subject is irradiated.

  FIG. 10 is an explanatory diagram of the autofocus auxiliary light emission method according to the present embodiment. In FIG. 10, reference numeral 120 denotes a digital camera, reference numeral 2 denotes an imaging lens, reference numeral 5 denotes a strobe light emission window, reference numeral 8 denotes a shutter key, reference numeral 9 denotes a power button, reference numerals 121-1 to 121-3 denote R, G, and B. Projection LEDs that emit pattern light, reference numerals 122-1 to 122-3 indicate R, G, and B pattern lights projected from the projection LEDs 121-1 to 121-3. The schematic operation of the digital camera according to the present embodiment at the time of flash photography is the same as the operation shown in the flowchart of FIG.

In the present embodiment, as shown in FIG. 10, light projection LEDs 122-1, 122-2, and 122-3 that emit R, G, and B pattern light are provided on the front surface of the main body of the digital camera 120. , B light emitting LEDs 122-1, 122-2, 122-3 are caused to emit light simultaneously or in order (different timings), and R, G, B pattern light is projected. The R, G, and B light emitting LEDs 122-1, 122-2, and 122-3 that emit the same pattern light may be caused to emit light at different timings.
In addition, in order to attach a pattern to the light from R, G, B, a pattern forming device (here, transmissive liquid crystal) is installed on the front surface of the light emitting LED. By driving the LED and projecting light after forming the pattern, it is possible to project light having a predetermined pattern.
Here, the pattern forming apparatus is used to add a pattern to the light projection, but this is not necessary. The pattern may be formed by ON / OFF control of the small light emitting portion. By allowing such a configuration, the degree of freedom in design is improved.

  In FIG. 11, when the shutter key 8 is fully pressed in step S4 of FIG. 4, the control unit 22 takes out pre-emission pattern data stored in a memory such as a ROM, and multi-emission control unit 34 together with a control signal. A control signal to drive the transmissive liquid crystals of the R, G, and B light emitting LEDs 122-1, 122-2, and 122-3, and set the contrast pattern for each light emitting LED. (Step S6-1), a drive control signal is sent to the multi-emission control unit 34, and the projection LED is caused to emit light with a predetermined amount of light at predetermined time intervals to irradiate the subject with an R, G, B contrast pattern. Then, the light amount of the subject is detected from the luminance signal from the color process circuit 18, and the light of the strobe is adjusted based on the detected value (step S6-2).

  Next, the control unit 22 determines whether or not the contrast pattern irradiated to the subject is appropriate for AF. If appropriate, the process proceeds to step S6-4. If not, the process returns to step S6-1 (step S6). -3).

  When the contrast pattern irradiated to the subject is appropriate for AF, the control unit 22 sends a control signal to the strobe light emission window liquid crystal drive unit 33 to erase the contrast pattern displayed on the strobe light emission window 1. 4 proceeds to step S7 (step S6-4).

  Specifically, as shown in the explanatory diagram of FIG. 12, in step S6-2, the contrast pattern of the R projection LED 122-1 is "1", the contrast pattern of the G projection LED 122-2 is "2", The contrast pattern of the B light emitting LED 122-3 is set to “3”, and AF auxiliary light is emitted. Then, in step S6-3, it is determined whether or not the contrast pattern irradiated to the subject is appropriate for AF. If there is, the AF operation is performed in step S7 via the route of S6-4, and if not appropriate, the AF auxiliary light emission operation of step S6-2 is repeated cyclically.

  When the operation shown in the flowchart of FIG. 11 and the explanatory diagram of FIG. 12 makes it difficult to obtain the contrast data suitable for AF with a single light due to the reflectivity, shape, pattern, etc. of the subject, making it impossible to focus. However, it becomes easier to acquire contrast data when a plurality of LEDs having different colors and light emission patterns emit light simultaneously or in a predetermined order.

<Modification 1>
In the flowchart of FIG. 11 and the explanatory diagram of FIG. 12, the contrast pattern formed for each of the R, G, and B light emitting LEDs is repeatedly irradiated without changing the object. The subject is repeatedly irradiated without changing the contrast pattern formed for each light emitting LED, but if the irradiated contrast pattern is not suitable for AF, the light emitting LED for each of R, G, and B You may make it irradiate by changing a contrast pattern, respectively. In this example, the number of patterns is nine, but the number is not limited to nine. In addition, although the repeated cycle is 3, it is not limited to 3.

  Specifically, as shown in the explanatory diagram of FIG. 13, in step S6-2, the contrast pattern of the R projection LED 122-1 is "1", the contrast pattern of the G projection LED 122-2 is "2", In step S6-3, it is determined whether or not the contrast pattern is appropriate for AF after the AF auxiliary light is emitted by setting the contrast pattern of the B light emitting LED 122-3 to "3". In step S6-3, the contrast pattern of the LED 122-1 is changed to “4”, the contrast pattern of the G light emitting LED 122-2 is changed to “5”, and the contrast pattern of the B light emitting LED 122-3 is changed to “6”. It is determined whether or not the contrast pattern is appropriate for AF. If not, the LED 12 is further selected in step S6-3. The contrast pattern of -1 is changed to "7", the contrast pattern of the G projection LED 122-2 is changed to "8", and the contrast pattern of the B projection LED 122-3 is changed to "9". It is determined whether or not the contrast pattern irradiated to is appropriate for AF. If not, the operation of returning to step S6-1 is repeated cyclically. If the contrast pattern is appropriate for AF, the AF operation is performed in step S7 via the route S6-4.

  In this way, by sequentially changing the contrast pattern of the R, G, and B light emitting LEDs and irradiating the AF auxiliary light, it is possible to focus on another pattern even if it is inappropriate for AF.

<Modification 2>
In the example shown in FIGS. 11 to 13, it is determined whether or not the contrast pattern is appropriate for AF after irradiating the subject once with the contrast pattern formed for each of the R, G, and B light emitting LEDs. However, after the contrast pattern formed for each of the R, G, and B light emitting LEDs is irradiated a plurality of times, it may be determined whether or not the contrast pattern is suitable for AF. In this example, the number of patterns is nine, but the number is not limited to nine. In addition, although the repeated cycle is 3, it is not limited to 3.

  Specifically, as shown in the explanatory diagram of FIG. 14, in step S6-2, the contrast pattern of the R projection LED 122-1 is "1", the contrast pattern of the G projection LED 122-2 is "2", The subject is irradiated with the contrast pattern of B light emitting LED 122-3 as "3", the contrast pattern of LED 122-1 is "4", the contrast pattern of G light emitting LED 122-2 is "5", B After changing the contrast pattern of the projection LED 122-3 to "6" and irradiating the subject, it is determined in step S6-3 whether or not the contrast pattern irradiated to the subject is appropriate for AF. If not, in step S6-3, the subject is irradiated from each projection LED with the same contrast pattern, and further, the R projection L After changing the contrast pattern of D122-1 to “7”, the contrast pattern of G light emitting LED 122-2 to “8”, the contrast pattern of B light emitting LED 122-3 to “9”, and irradiating the subject In step S6-3, it is determined whether or not the contrast pattern irradiated to the subject is appropriate for AF. If not, in step S6-3, the subject is irradiated from each projection LED with the same contrast pattern. Furthermore, the contrast pattern of the R LED 122-1 is changed to "1", the contrast pattern of the G LED 122-2 is changed to "2", and the contrast pattern of the B LED 122-3 is changed to "3". The contrast pattern irradiated to the subject in step S6-3 was appropriate for AF. It determines whether, if not appropriate to repeat the operation returns to step S6-1 cyclically. If the contrast pattern is appropriate for AF, the AF operation is performed in step S7 via the route S6-4.

  In this way, by sequentially changing the contrast pattern of the R, G, and B light emitting LEDs and irradiating the AF auxiliary light, it is possible to focus on another pattern even if it is inappropriate for AF. In addition, since a plurality of patterns are irradiated before determining whether or not the contrast pattern is appropriate for AF, the chance of obtaining and focusing an appropriate pattern for AF is accelerated.

(Embodiment 4)
FIG. 15 is an explanatory diagram of an autofocus auxiliary light emission method according to the present embodiment, in which FIG. 15 (a) shows the front and FIG. 15 (b) shows the back. In FIG. 15, reference numeral 130 is a digital camera, reference numeral 2 is an imaging lens, reference numeral 3 is a mode dial, reference numeral 5 is a flash light emission window, reference numeral 6-1 is a cursor key, reference numeral 6-2 is a SET key, and reference numeral 8 is a shutter key. Reference numeral 9 is a power button, reference numeral 13 is a multi-projection LED in which a plurality of LEDs are two-dimensionally arranged, reference numeral 15 is an AF auxiliary light irradiation range displayed on the liquid crystal monitor screen 4, and reference numeral 14 is an AF auxiliary light irradiation range 15. An AF frame to be displayed is shown.

  In this embodiment, a multi-multi-projection LED 13 in which a plurality of projection LEDs are two-dimensionally arranged as shown in FIG. 15 is provided on the front surface of the digital camera 130, and each LED in the multi-projection LED 13 emits light simultaneously during multi-AF. .

FIG. 16 is a flowchart showing an example of a schematic operation at the time of flash photography of the digital camera 130 according to the present embodiment. This flowchart explains a program for causing the computer of the digital camera 130 to realize the autofocus assist function of the present invention. Is for. The following processing will be basically described by an example in which the control unit 22 executes according to a program stored in advance in a program storage memory such as a flash memory, but it is not necessary to store all functions in the program storage memory. Accordingly, a part or all of the information may be received via a network. Hereinafter, description will be given based on FIGS. 15 to 18.
In this case, the pattern is not formed by the pattern forming apparatus such as the LCD as described above, but the pattern is formed by turning on / off a plurality of small light emitting units. You may comprise so that a light emission pattern may be formed with an apparatus.
Further, for example, a pattern forming device may be provided on the front surface of each LED that is a small light emitting unit so that a finer pattern can be formed. With this configuration, AF with higher reliability can be performed.

  In FIG. 16, when the shooting mode is selected when the power is turned on, the control unit 22 performs initial setting of shooting conditions and the like (step T1), and performs the AE process for the through image at the focal length corresponding to the zoom value at that time. The color process circuit 18 obtains image data from the CCD 13 and performs white balance (AWB) processing, and then starts DMA transfer to the DRAM 21 via the DMA controller 19 and the DRAM interface (I / F) 20. Is rewritten with video through image data obtained by thinning out image data from the CCD 13, and a through image is displayed on the liquid crystal monitor screen 4 of the display unit 26. Further, although not shown in the drawing, zoom processing with an instruction based on a zoom operation is performed to move the zoom lens 12-1 to a designated position (step T2).

  The control unit 22 obtains the luminance of the subject from the luminance signal from the color process circuit 18 and compares it with a predetermined value to check whether or not strobe light emission is necessary. If strobe light emission is necessary, the process proceeds to step T4. The process proceeds to a normal photographing process (not shown) (step T3).

  The control unit 22 checks whether or not the shutter key 8 has been half-pressed based on a signal from the key input unit 30. If the shutter key 8 has been pressed halfway, the shutter key 8 is locked and the process proceeds to step T5. In this case, the process returns to step T2 (step T4). In addition, the control unit 22 sends a control signal to the multi-emission control unit 34, causes the LEDs in the multi-projection LED 13 to emit light at the same time to irradiate the subject (step T5), and determines the subject from the luminance signal from the color process circuit 18. The amount of light is detected, and the light of the strobe is adjusted based on the detected value (step T6).

  Next, the control unit 22 acquires (ranging) a plurality of in-focus positions on the subject and camera distances based on each pattern (AFAF auxiliary light) emitted to the subject by the light emitted from the multi-projection LED 13. Focus detection is performed with respect to the in-focus position, and the desired in-focus position is focused (that is, multi-AF is performed), and AE processing for main photographing based on through-image data captured when the shutter key 8 is half-pressed Then, automatic white balance (AWB) processing is performed, and the process proceeds to step T8. During this time, the VRAM 24 is rewritten with through image data obtained by thinning out the image data from the CCD 13 until the multi-AF processing is completed, and a through image is displayed on the liquid crystal monitor screen 4 of the display unit 26 (step T7).

  The control unit 22 checks whether or not the multi-AF process or the like has been completed. If the multi-AF process or the like has been completed, the process proceeds to step T9. If not, the process returns to step T7 (step T8).

  When the control unit 22 releases the lock state of the shutter key 8 to enable the operation, the control unit 22 checks whether or not the shutter key 8 is fully pressed based on a signal from the key input unit 30, and when the full press operation is performed. Advances to T10 (step T9).

  When the shutter key 8 is fully pressed, the control unit 22 sends a drive control signal to the strobe driving unit 31 to cause the strobe light emitting unit 32 to perform main light emission (step T10), and at that time, the path from the CCD 13 to the DRAM 21 is immediately established. After stopping and switching to the CCD driving method at the time of actual photographing different from the through image acquisition, the image data is subjected to image compression processing, and then the compressed image data (image file) is stored in the storage memory 28. And the image capturing for one frame is finished (step T11).

  With the operation shown in the flowchart of FIG. 16 above, each LED of the multi-projection LEDs emits light simultaneously during multi-AF, so that AF using AF auxiliary light can be performed in all AF frames.

<Modification>
In the explanatory diagram of FIG. 15 and the flowchart of FIG. 16, multi AF is used as an example. However, when one of a plurality of AF frames is selected and focused, the multi-projection LED 13 corresponds to the AF frame. You may make it light-emit LED.

  FIG. 17 is an explanatory view of an autofocus auxiliary light emission method according to this modification, in which FIG. 17 (a) shows the front and FIG. 17 (b) shows the back. In FIG. 17, reference numeral 130 denotes a digital camera, reference numeral 5 denotes a strobe light emission window, reference numeral 13 denotes a multi-projection LED in which a plurality of LEDs are two-dimensionally arranged, and reference numeral 13-3 denotes a projection corresponding to the selected AF frame 14-3. The light LED, reference numeral 15-3 represents an AF auxiliary light irradiation range related to the selected AF frame, and reference numeral 15-3 represents the selected AF frame.

  FIG. 18 is a flowchart showing a schematic operation example when the digital camera 100 according to the present embodiment performs strobe shooting. Hereinafter, description will be made based on FIG. 9, FIG. 17, and FIG. Note that the operations in steps T1 to T3 and steps T9 to T11 in FIG. 19 are the same as the operations shown in the flowchart in FIG.

  In FIG. 18, when the user presses the key 10 at the subsequent stage or the previous stage of step T3, the selection menu is displayed. When the multi AF frame selection menu is further selected, the multi AF frame is displayed on the through image. Therefore, the control unit 22 checks which AF frame is selected based on the signal from the key input unit 30 (step T4-1).

  Next, the control unit 22 checks whether or not the shutter key 8 has been half-pressed based on a signal from the key input unit 30, and if there has been a half-press operation, locks the shutter key 8 and proceeds to step T5. If not, the process returns to Step T2 (Step T4-2).

  When the shutter key 8 is half-pressed in step T4-2, the control unit 22 sends a control signal to the multi-emission control unit 34, and the LED in the multi-projection LED 13 is selected in step T4-1. The LED corresponding to the AF frame is caused to emit light to irradiate the corresponding part of the subject (step T5), the light amount of the subject is detected from the luminance signal from the color process circuit 18, and the flash is adjusted based on the detected value. (Step T6).

  Next, the control unit 22 obtains (measures) the distance between the designated in-focus position on the subject and the camera based on each pattern (AF auxiliary light) emitted to the subject by light emission of the LED corresponding to the selected AF frame. The focus is detected at a distance, and the focus is adjusted (that is, AF is performed at the designated in-focus position), and the AE processing for the main photographing based on the through image data captured when the shutter key 8 is half-pressed, and An automatic white balance (AWB) process is performed, and the process proceeds to step T8. During this time, the VRAM 24 is rewritten with through image data obtained by thinning out the image data from the CCD 13 until the AF processing is completed, and a through image is displayed on the liquid crystal monitor screen 4 of the display unit 26 (step T7).

  The control unit 22 checks whether or not the AF process or the like is finished. If the AF process or the like is finished, the process proceeds to Step T9, and if not finished, the process returns to Step T7 (Step T8).

  By the operation shown in the flowchart of FIG. 18, the LED corresponding to the selected AF frame among the multi-projection LEDs emits light at the time of AF, so that AF using the AF auxiliary light can be performed within the selected and designated AF frame. Become.

  In addition, the AF frame may be moved (free AF) without being limited to multi-AF, and the LED corresponding to the destination AF frame emits light even when the AF frame is moved (free AF). , AF using AF auxiliary light can be performed.

  In addition, an area for storing a contrast pattern in which AF has succeeded is secured in the storage memory of the digital cameras 100, 120, and 130, and in each of the above embodiments, pattern data in which AF auxiliary light is formed when AF has succeeded is stored. In addition, at the time of the next shooting, the control unit 22 may preferentially perform the AF auxiliary light irradiation using the pattern data stored in the storage area. With this configuration, the possibility of AF success in the next shooting is high, and the power consumption of the light emitting means such as a strobe can be saved.

  The method described in each of the above embodiments can be applied to various apparatuses by being written in a recording medium such as a flash memory, a hard disk, or a removable memory card as a program that can be executed by a computer, or the program itself. Can be transmitted by a transmission medium such as a network and applied to each device. The computer of various apparatuses reads the program recorded on the recording medium or the program provided via the transmission medium, and the operation is controlled by this program, thereby executing each process and realizing the present technique.

  In each of the above embodiments, a digital camera is taken as an example of the imaging apparatus. However, the imaging apparatus to which the present invention can be applied is not limited to a digital camera, and various modifications can be made. Absent. For example, the term imaging device can be applied to a digital camera, a camera-equipped mobile phone, and an information device having an imaging unit.

  The present invention is not limited to the above-described embodiments and modifications as they are, and can be embodied by modifying the components without departing from the spirit of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

It is a figure which shows an example of the external appearance structure of the digital camera as an Example of the imaging device concerning Embodiment 1-3. FIG. 2 is a block diagram illustrating an example of a circuit configuration of the digital camera in FIG. 1. It is explanatory drawing of the auto-focus AF auxiliary light emission method. 6 is a flowchart showing an example of a schematic operation when the digital camera according to the present invention performs flash photography. 6 is a flowchart illustrating a setting of a light emission pattern of the digital camera and a light emission control operation of AF auxiliary light according to the first embodiment. 10 is a flowchart showing a light emission pattern setting and AF auxiliary light emission control operation of a digital camera according to a modification of the first embodiment. 10 is a flowchart illustrating an example of a schematic operation when the digital camera according to the second embodiment performs strobe shooting. 10 is a flowchart illustrating a setting of a light emission pattern of the digital camera and a light emission control operation of AF auxiliary light according to the second embodiment. It is explanatory drawing of the setting of the light emission pattern of the digital camera concerning the modification of Embodiment 2, and the light emission control operation of AF auxiliary light. 6 is a block diagram showing an example of a circuit configuration of a digital camera as an example of an imaging apparatus according to Embodiments 3 and 4. FIG. It is explanatory drawing of the autofocus auxiliary | assistant light emission method concerning Embodiment 3. FIG. 10 is a flowchart illustrating a light emission pattern setting and AF auxiliary light emission control operation of the digital camera according to the third embodiment. It is explanatory drawing of the setting of the light emission pattern of the digital camera concerning Embodiment 3, and the light emission control operation of AF auxiliary light. It is explanatory drawing of the setting of the light emission pattern of the digital camera concerning the modification 1 of Embodiment 3, and the light emission control operation of AF auxiliary light. It is explanatory drawing of the setting of the light emission pattern of the digital camera concerning the modification 2 of Embodiment 3, and the light emission control operation of AF auxiliary light. It is explanatory drawing of the autofocus auxiliary | assistant light emission method concerning Embodiment 4. FIG. 14 is a flowchart illustrating an example of a schematic operation when the digital camera according to the fourth embodiment performs strobe shooting. It is explanatory drawing of the autofocus auxiliary | assistant light emission method concerning the modification of Embodiment 4. 14 is a flowchart illustrating a schematic operation example at the time of flash photography of a digital camera according to a modification of the fourth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Strobe light emission window 8 Shutter key 11-1 AF drive part 12-2 Autofocus lens 13 Multi-projection LED
15 AF frame 22, 50 Control unit 28 Storage memory 31, 63 Strobe drive unit 32, 64 Strobe light emission unit 33, 65 Strobe window liquid crystal drive unit 100, 120, 130 Digital camera 121-1 to 121-3 Projection LED
500, 600 Mobile phone with camera

Claims (19)

A light emitting means for emitting AF auxiliary light which is auxiliary light for autofocus;
Pattern control means for variably configuring a light emission pattern of auxiliary light emitted by the light emitting means;
Photometric means for measuring the light reflected from the subject by the auxiliary light emitted from the light emitting means;
AF that performs automatic focusing based on a plurality of photometric results of the auxiliary light emitted by the photometric means while the auxiliary light is emitted by the light emitting means while changing the pattern of a plurality of predetermined light emitting patterns by the pattern control means. Means,
AF success / failure determination means for determining the success or failure of AF by the AF means;
An AF re-execution unit that, when the AF success / failure determination unit determines that AF is not established, changes a combination of a plurality of light emission patterns in one AF operation by the AF unit, and tries AF again;
An imaging device comprising: Claim storage means for storing the illumination pattern AF has been fulfilled, the next time imaging, and performs irradiation of the AF assist light using the light-emitting pattern stored in preferentially the storage means 1 the image pickup apparatus according to. The pattern control means performs by controlling the transmission type liquid crystal which is placed in front of the light emitting portion, the light emitting pattern imaging device according to claim 1 or 2, characterized in that conducted by controlling the pattern . The imaging apparatus according to any one of claims 1 to 3 , wherein the pattern control unit controls a pattern by turning each of a plurality of LEDs constituting the light emitting unit on and off. The imaging apparatus according to any one of claims 1 to 4 , wherein the light emitting unit is used to emit light of a flash and AF auxiliary light. The imaging apparatus according to claim 5 , wherein the AF auxiliary light is used in combination with pre-emission that performs flash light control. A light emitting means for emitting AF auxiliary light, which is auxiliary light for autofocus, in a plurality of colors ;
Pattern control means for variably configuring the light emission pattern and emission color of the auxiliary light emitted by the light emission means;
Photometric means for measuring the light reflected from the subject by the auxiliary light emitted from the light emitting means;
Wherein the pattern emission pattern constituted by the control unit and the emission color of the assist beam by Ri onset is light to the light emitting means, and AF means for autofocus from the photometry result of the auxiliary light by the photometry means,
AF success / failure determination means for determining the success or failure of AF by the AF means;
An AF re-execution unit that resets a light emission pattern and a light emission color by the pattern control unit and tries AF again when the AF success / failure determination unit determines that AF is not established;
An imaging device comprising: The imaging apparatus according to claim 7, wherein the pattern control unit is provided for each light source provided for each of the plurality of colors, and the pattern is variably configured for each light source. The imaging apparatus according to claim 8, wherein AF is performed without changing a pattern by the pattern control unit every time AF is performed by the AF unit. The imaging apparatus according to claim 8, wherein AF is performed by changing a pattern by the pattern control unit each time AF is performed by the AF unit. The AF means performs light emission by the light emitting means and accompanying photometry by the photometry means a plurality of times in one AF, and the light emission and photometry in the single AF by the AF means is performed in the pattern. The image pickup apparatus according to claim 8, wherein the image pickup device is performed while changing the pattern by the control means. Storage means for storing the illumination pattern AF has been fulfilled, the next time shooting, claim, characterized in that irradiation is performed preferentially using said light-emitting patterns stored in the storage unit AF auxiliary light 7 The imaging device of any one of thru | or 11. The said pattern control means is performed by controlling the transmissive liquid crystal installed in the front surface of the said light emission part, The said light emission pattern is performed by controlling a pattern, The any one of Claims 7 thru | or 11 characterized by the above-mentioned. The imaging device described in 1. The image pickup apparatus according to any one of claims 7 to 11, wherein the pattern control means controls a pattern by ON / OFF of each of a plurality of LEDs constituting the light emitting unit. The light emitting means, the image pickup apparatus according to claim 7 to 14, characterized in that it is configured to emit the three primary colors by the RGB. A light emitting step of emitting AF auxiliary light which is auxiliary light for autofocus;
A pattern control step for controlling a light emission pattern of auxiliary light emitted by the light emission step;
A photometric step of measuring the light reflected by the subject by the auxiliary light emitted by the light emitting step;
While a plurality of light emitting patterns which are predetermined to change the pattern by the pattern control step, said light-emitting step by emits auxiliary light, AF step of performing autofocus from multiple photometry result of the auxiliary light by the photometry process When,
AF success / failure determination step for determining the success or failure of AF in the AF step;
When the AF success / failure determination step determines that AF is not established, an AF re-execution step of changing the combination of a plurality of light emission patterns in one AF operation by the AF step and attempting AF again;
An autofocus method characterized by comprising: On the computer,
A light emitting function for emitting AF auxiliary light which is auxiliary light for autofocus;
A pattern control function for controlling a light emission pattern of auxiliary light emitted by the light emission function;
A photometric function for measuring the light reflected by the subject by the auxiliary light emitted by the light emitting function;
AF function that emits auxiliary light by the light emission function while changing the pattern of a plurality of predetermined light emission patterns by the pattern control function, and performs autofocus from a plurality of light measurement results of the auxiliary light by the photometry function When,
An AF success / failure determination function for determining the success or failure of AF by the AF function;
Wherein the AF success determining function, when the AF is determined to be satisfied, by changing the combination of a plurality of light emitting patterns in a single AF operation that by the AF function, AF redo function trying AF again When,
A program characterized by having executed. A light emission step of emitting AF auxiliary light, which is auxiliary light for autofocus, in a plurality of colors ;
A pattern control step for controlling the light emission pattern and emission color of the auxiliary light emitted by the light emission step;
A photometric step of measuring the light reflected by the subject by the auxiliary light emitted by the light emitting step;
And AF step of performing autofocus from the pattern control controlled emission pattern and the emission color of the auxiliary light emitted by said light emitting step by step, the auxiliary light photometry result of the photometry process,
AF success / failure determination step for determining the success or failure of AF in the AF step;
An AF re-execution step in which, when the AF success / failure determination step determines that AF is not established, the light emission pattern and the light emission color are reset by the pattern control step and AF is attempted again;
An autofocus method characterized by comprising: On the computer,
A light emitting function that emits AF auxiliary light, which is auxiliary light for autofocus, in multiple colors ;
A pattern control function for controlling a light emission pattern and a light emission color of auxiliary light emitted by the light emission function;
A photometric function for measuring the light reflected by the subject by the auxiliary light emitted by the light emitting function;
An AF function that emits auxiliary light of a light emission pattern and emission color controlled by the pattern control function by the light emission function, and performs autofocus from a photometric result of the auxiliary light by the photometric function;
An AF success / failure determination function for determining the success or failure of AF by the AF function;
By the AF success determining function, when the AF is determined to be not satisfied, reset the that by the pattern control function emission pattern and the light emitting colors, and AF redo function trying AF again,
A program characterized by having executed.

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