JPH08184751A - Camera - Google Patents

Abstract

PURPOSE: To realize quick focusing and to prevent the energy of a battery from being wastefully consumed. CONSTITUTION: This camera is provided with an auxiliary light selection means selecting either of a built-in auxiliary light means 502a and an externally attached auxiliary light means 503a which is attached to the camera as an auxiliary means based on current information on a subject distance in the case the auxiliary light is required at the time of autofocusing. Since parallax with reference to a photographing optical axis is small in the auxiliary light means 502a and it is large in the auxiliary light means 503a, the current information on the subject distance is obtained and the auxiliary light means 502a and 503a are properly used based on the obtained information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a camera which can be equipped with an external strobe device or the like having an external auxiliary light unit for autofocus and which has an internal auxiliary light unit for autofocus. Is.

[0002]

2. Description of the Related Art Conventionally, when an external strobe device having an auxiliary light unit is attached to a camera having an auxiliary light unit for autofocus (AF), an AF using only the auxiliary light built in the camera is used. It is a general usage of the auxiliary light whether to preferentially perform the auxiliary light or the AF using only the external auxiliary light.

Further, in the proper use of the two auxiliary light means,
In Japanese Patent Laid-Open No. 1-287630, in a camera capable of controlling an auxiliary light unit that uses the same power source for driving a lens and an auxiliary light unit that uses a different power source for lens driving, an auxiliary light unit on a different power source side during lens driving There is one that uses.

As a method for switching the characteristics of the auxiliary light, as shown in Japanese Patent Application Laid-Open No. 1-288717, a method of switching between auxiliary light of a narrowed light beam and an unfocused light beam, and Japanese Patent Application Laid-Open No. 1-291112 are used. As shown in No. 6, there is a method in which the emission direction of the auxiliary light is moved with respect to the optical axis depending on whether or not the auxiliary light pattern is received.

[0005]

However, in all of the above-mentioned conventional examples, when the external strobe device having the auxiliary light means is attached to the camera in which the auxiliary light means is built in, the built-in auxiliary light means takes a picture. Based on the characteristics of the two auxiliary light means that the parallax (parallax between the auxiliary light illumination range and the shooting range) is small with respect to the optical axis, but the external auxiliary light means has a large parallax with respect to the shooting optical axis. Also, the effective use of each auxiliary light was not performed properly.

(Object of the Invention) It is an object of the present invention to provide a camera capable of quick focusing and preventing wasteful consumption of battery energy.

[0007]

In order to achieve the above object, the present invention according to claim 1 is based on current subject distance information when auxiliary light is required during autofocus.
Provided is auxiliary light selecting means for selecting either the built-in auxiliary light means or the external auxiliary light means mounted on the camera as the auxiliary light means. The built-in auxiliary light means has a small parallax with respect to the photographing optical axis. Since the external auxiliary light unit has a large parallax with respect to the photographing optical axis, the current object distance information is obtained, and the built-in auxiliary light unit and the external auxiliary light unit are selectively used based on this.

In order to achieve the above object, the present invention according to claim 2 is such that, when auxiliary light is required during autofocus, the current focus position is on the short distance side by the focus position detecting means. If it is detected, the built-in auxiliary light means is selected as the auxiliary light means, and if it is detected that it is on the far side, the auxiliary light selection means for selecting the external auxiliary light means as the auxiliary light means. The built-in auxiliary light unit and the external auxiliary light unit are selectively used depending on whether the current focus position is on the short distance side or the long distance side.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

FIG. 2 is a block diagram of a camera according to the first embodiment of the present invention. In FIG. 2, reference numeral 1 is a microcomputer for controlling the movement of each part of the camera.
Reference numeral 2 denotes a lens control circuit, which drives and controls a focus adjusting motor and a diaphragm blade controlling motor (not shown) of the taking lens, and while receiving the LCOM signal from the microcomputer 1, via a data bus DBUS. Perform serial communication. When the lens drive information is received from the microcomputer 1 by serial communication, the lens drive control is performed based on the information. At the same time, various lens information (focal length information and the like) is sent to the microcomputer 1 by serial communication.

Reference numeral 3 denotes a liquid crystal display circuit for driving the liquid crystal displays 11 and 12 for notifying the photographer of the remaining battery power of the camera and the number of photographed images.
While receiving the OM signal, serial communication is performed via the data bus DBUS. Then, when display data is received from the microcomputer 1 by serial communication, the liquid crystal displays 11 and 12 are driven according to the data.

Reference numeral 4 denotes a switch sense circuit, which reads the state of a switch for the photographer to set each photographing condition and the state of the camera, and the microcomputer 1
The switch data is sent to the microcomputer 1 by serial communication via the data bus DBUS while receiving the SWCOM signal.

Numeral 5 is a strobe light emission dimming control circuit for controlling strobe light emission and a light emission stopping function by TTL dimming, and while receiving the STCOM signal, the data bus DBU
Serial communication is performed with the microcomputer 1 via S, data relating to strobe control is received, and various controls are performed. In addition, this circuit is based on the external strobe device 14
Also works as an interface when is attached to the camera. Therefore, when the external strobe device 14 is attached, it communicates with the external strobe device 14 and sends to the microcomputer 1 information as to whether or not auxiliary light means is provided. On the contrary, it also serves to transmit the control signal from the microcomputer 1 to the external strobe device 14.

Reference numeral 6 denotes a focus detection circuit, which is a line sensor for performing AF by the existing phase difference detection method and a circuit unit for reading and storing the line sensor, which is controlled by the microcomputer 1.

The microcomputer 1 performs distance measurement by an existing algorithm based on the A / D value of the sensor output of the focus detection circuit 6, calculates the lens drive amount, and then focuses the lens control circuit 2 The lens drive amount obtained by calculation is communicated to drive the lens to bring it into focus. If AF auxiliary light on the external strobe device 14 side is required, the auxiliary strobe device 14 communicates with the external strobe device 14 through the strobe emission dimming control circuit 5 immediately before the focus detection circuit 6 starts accumulation. Means, turn off the auxiliary light means after accumulation, read the sensor output to calculate the lens drive amount,
On the other hand, when the auxiliary light of the built-in auxiliary light means is required, the built-in auxiliary light drive circuit 15 turns on the built-in auxiliary light immediately before the focus detection circuit 6 starts the accumulation, and the auxiliary light means is turned on after the accumulation. The light is turned off, the sensor output is read, and the lens drive amount is calculated.

Reference numeral 7 denotes a photometric circuit, which measures a subject and sends a photometric output to the microcomputer under the control of the microcomputer 1. The microcomputer 1 A / D-converts the sent photometric output and uses it for setting exposure conditions (aperture, shutter speed). Reference numeral 8 denotes a shutter control circuit, which controls traveling of a shutter front curtain and a rear curtain (not shown) according to a control signal from the microcomputer 1.

A feeding motor / charge motor control circuit 9 feeds (winds or rewinds) the film in accordance with a control signal from the microcomputer 1. The motor control circuit 9 also controls the up / charge (mirror down) motor of the quick return mirror.

SW1 is a switch for starting the photographing preparation operation of the camera. When the microcomputer 1 recognizes that the switch SW1 is turned on, it starts photometry, distance measurement and display. SW2 is a switch for starting the photographing operation of the camera, and when the microcomputer 1 recognizes that the switch SW2 is turned on, the exposure operation is started. The X contact is turned on at the timing when the traveling of the front curtain of the shutter is completed, and serves to inform the strobe light emission dimming control circuit 5 of the timing of strobe light emission. SW3 is the camera mode (TV priority, AV priority,
It is a mode selector switch for switching between manuals and programs.

Reference numeral 10 is an electronic dial for changing a TV value, an AV value, a mode and the like. For example, when the electronic dial 10 is rotated while pressing the mode changeover switch SW3, "TV priority" → "AV priority" → "manual" →
The mode is changed in the order of "program"->"TVpriority"->"AVpriority"->"manual"->"program" ..., and the mode intended by the photographer can be set. Also, when the electronic dial 10 is rotated in the reverse direction, "Program" →
The mode is changed from "manual" to "AV priority" to "TV priority" to "program" to ... In addition, "TV priority" is set by the mode switch 3 and the electronic dial 10.
If is set as a mode, the electronic dial 10 is rotated to allow the TV set desired by the photographer.
You can set the value. When "AV priority" is set as the mode by the mode changeover switch 3 and the electronic dial 10, the electronic dial 10 can be rotated to set the AV value desired by the photographer. .

An external display device 11 is driven by the liquid crystal display circuit 3. Reference numeral 12 denotes an in-finder liquid crystal display device, which is similarly driven by the liquid crystal display circuit 3. A replaceable lens 13 is controlled by the lens control circuit 2. Reference numeral 14 denotes an external strobe device having a built-in auxiliary light, which is controlled through the strobe light emission control circuit 5. Further, the external strobe device 14 has a power source separate from the camera body. 15 is a built-in auxiliary light drive circuit,
This is a circuit for driving an auxiliary light unit for AF (not shown) built in the camera.

Next, the operation of the camera (operation of the microcomputer 1) will be briefly described with reference to the flowchart of FIG. [Step 301] The power of the camera is turned on due to a factor such as the pressing of the main switch of the camera, and the process proceeds to step 302. [Step 302] Here, it is determined whether or not the switch SW1 is turned on, and if it is turned on, the process proceeds to step 306 to perform the photometric operation, and if it is kept off, whether the power is turned off or not is determined. Step 30 of determining
Go to 3.

It is assumed here that the switch SW1 remains off, and the process proceeds to step 303. [Step 303] It is determined whether or not the power is turned off. If the power is turned off, the process proceeds to step 304, and OF
If not, the process returns to the check of the switch SW1 in step 302.

That is, when the power of the camera is turned on for some reason, the power is turned on for a certain period of time to check the switch state and switch the display. [Step 304] The liquid crystal display circuit 3 turns off the display of unnecessary portions inside or outside the viewfinder of the camera, and the power is turned off.

In step 302 above, the switch S
Step 30 is performed by determining that W1 is turned on.
Go to 6. [Step 306] The photometry circuit 7 is operated to capture the photometry of the subject, A / D-convert it, and calculate / set the exposure conditions (aperture, shutter speed). [Step 307] The focus detection circuit 6 is used to store the line sensor and the sensor output is taken in, and the defocus amount is calculated by an existing algorithm based on the A / D value (hereinafter, referred to as “distance measurement” for convenience). ) The calculation is performed to calculate the lens drive amount, and then the lens drive amount is communicated to the lens control circuit 2 so that the lens is focused, and the lens is driven and focused.

At this time, the AF on the external strobe device 14 side
If auxiliary light is required, just before the focus detection circuit 6 starts the accumulation, it communicates with an external strobe device through the strobe emission dimming control circuit 5 to turn on the auxiliary light means, and after the accumulation, the auxiliary light is emitted. To turn off. When auxiliary light from the built-in auxiliary light means is required, the built-in auxiliary light driving circuit 15 turns on the built-in auxiliary light means immediately before the focus detection circuit 6 starts the accumulation, and turns off after the accumulation. [Step 308] The liquid crystal display circuit 3 displays the AV value and the TV value calculated / set in the above step 306 on the in-viewfinder liquid crystal 12 and the external display 11. If the result of the distance measurement in step 307 is in-focus, the in-focus display is also performed. [Step 309] Here, it is determined whether or not the state of the camera is a state in which the release is permitted. For example, AF
If the mode is the "one-shot mode", the release is permitted if the distance measurement result of the step 307 is in focus, and the step SW31 is executed to check the switch SW2.
If the focus is not 0 and the focus is not achieved, the process returns to step 302 to check the switch SW1, and if the switch SW1 is ON, photometry, distance measurement, and display are performed again.

When the release is permitted as described above, the process proceeds to step 310. [Step 310] It is determined whether or not the switch SW2 is ON, and if it is ON, the process proceeds to step 311 to perform a shooting operation, and if the switch SW2 is OFF, the process proceeds to step 302 to check the switch SW1. return,
Here, when SW1 is ON, photometry, distance measurement, and display are performed again. [Step 311] The feed motor / charge motor control circuit 9 raises the click return mirror, and the lens control circuit 2 communicates the aperture amount determined in step 306 to the lens 13 to obtain the set exposure amount. The narrowing operation is performed as follows. [Step 312] The shutter control circuit 8 is used to control the traveling of the shutter front curtain and the rear curtain (not shown) so that the TV amount determined in step 306 can be obtained. [Step 313] Here, the feed motor / charge motor control circuit 9 causes the quick return mirror to be moved down and at the same time the shutter is charged, and the aperture stopped down in step 306 is returned to open. [Step 314] The feed motor / charge motor control circuit 9 is used to control a feed motor (not shown) to wind the film.

The camera operation has been briefly described above.

The AF operation of step 307 will be briefly described below with reference to the flowchart of FIG. [Step 402] Based on the result of the distance measurement performed last time, it is determined whether or not auxiliary light is necessary in the distance measurement this time.
If it is determined that the auxiliary light is necessary for the distance measurement this time, step 4 is performed to turn on the auxiliary light before starting the accumulation.
If it is determined that the auxiliary light is not necessary, the step 403 for turning on the auxiliary light is skipped and the step 404 is performed.
Proceed to. [Step 403] AF on the external strobe device 14 side
When the auxiliary light is required, the external flash device 14 is communicated through the strobe light emission control circuit 5 to turn on the external auxiliary light unit, while the auxiliary light of the built-in auxiliary light unit is required. Causes the built-in fill light drive circuit 15 to turn on the built-in fill light means. [Step 404] The focus detection circuit 6 is used to start the accumulation operation of the line sensor, read the sensor output,
/ D conversion is performed. [Step 405] When the auxiliary light unit on the external strobe device 14 side is used in step 403, the auxiliary light unit is communicated with the external strobe device 14 through the strobe light emission control circuit 5, and the auxiliary light unit is turned off. Step 40 above
When the built-in fill light means is turned on in step 3, the built-in fill light drive circuit 15 turns off the built-in fill light means. [Step 406] Based on the A / D converted value of the above step 404, a prediction value is calculated by an existing algorithm, and the calculated value is communicated with the lens control circuit 2 to obtain the value of the currently used lens 13. The lens drive amount is calculated from the characteristic value of the lens. [Step 407] If the lens drive amount can be obtained in step 406, the lens control circuit 2 communicates with the lens 13 to drive the range ring. When the lens drive amount cannot be calculated in step 406 in the large blur state, the lens is not driven and the process proceeds to step 408.

Next, the difference in parallax between the built-in auxiliary light means and the external auxiliary light means will be described with reference to FIGS.

Reference numeral 501 is a lens. Reference numeral 502 is a camera body having a built-in auxiliary light unit 502a, and 505 is an irradiation range of the built-in auxiliary light unit 502a.
FIG. 7 shows a state in which only the auxiliary light unit 502a is turned on. Reference numeral 503 is an external strobe device having an auxiliary light unit 503a for AF, and 504 is an irradiation range of the external auxiliary light unit 503a. Only the external auxiliary light unit 503a is turned on in FIG. It shows the state of time. The external strobe device 503 is equipped with a battery as a dedicated power source, and the external auxiliary light unit 5 is used.
03a will also perform a light emission operation by this power supply.

From these figures, the subject 50 at a short distance can be seen.
6 is illuminated by the auxiliary light unit 502a built in the camera, but is not illuminated by the auxiliary light unit 503a provided in the external strobe device 503. That is, the external strobe device 50 having the auxiliary light unit 503a is incorporated in the camera including the auxiliary light unit 502a.
It is clear that when the third auxiliary member 502a is mounted, the built-in auxiliary light unit 502a has a small parallax with respect to the optical axis, but the external auxiliary light unit 503a has a large parallax with respect to the optical axis.

Therefore, when the AF is performed using the illumination type auxiliary light instead of the pattern projection as the auxiliary light, it is useless to light the auxiliary light having a large parallax when the subject is located at a short distance. .

Based on the above, the case where the auxiliary light is of the illumination type instead of the pattern projection will be described below with reference to the flowchart of FIG. [Step 102] Based on the result of distance measurement performed last time, it is determined whether or not auxiliary light is necessary in this distance measurement.
If it is determined that the auxiliary light is necessary for this distance measurement, the process proceeds to step 105 where it is checked whether or not there is an external auxiliary light unit for performing AF using the auxiliary light. If it is determined that the light unit is not necessary, the process proceeds to step 103 to perform AF without auxiliary light. [Step 103] Here, AF without auxiliary light is performed. Then, the process proceeds to step 104 to end this operation.

If it is determined in step 105 that auxiliary light is necessary, the process proceeds to step 105 as described above. [Step 105] Here, it is determined whether or not the external auxiliary light unit of the camera is attached. If not, the process proceeds to Step 106 to perform AF by the built-in auxiliary light unit, and the external auxiliary light unit is attached. If so, go to step 110 to input the distance ring position.

First, the case where the external auxiliary light unit is not attached will be described. [Step 106] Here, AF is performed by illuminating the built-in auxiliary light means. [Step 107] In the AF in Step 106, it is determined whether or not an image is found by the illumination of the built-in auxiliary light means. If the image is found by this built-in auxiliary light and the lens is driven, the process proceeds to Step 104, and the built-in auxiliary light is used. If the image cannot be found due to the large blurring state by the illumination of the auxiliary light, and the prediction value cannot be calculated at the current distance ring position, the distance ring is moved to perform AF again.
Proceed to. [Step 108] Here, because of AF again, if the current position of the range ring is closer than the middle position to the infinity end,
If it is infinite from the middle position, move the range ring to the closest end. [Step 109] AF is performed again by illuminating the built-in auxiliary light unit. Then, the process proceeds to step 104 to end this operation.

Next, the case where the external auxiliary light means is attached in step 105 will be described. [Step 110] Since the external auxiliary light means is attached, the position data is obtained by communicating with the lens 13 through the lens control circuit 2 to secure the current distance ring position. [Step 111] Based on the data result obtained in the above step 110, it is determined whether or not the current distance ring position is on the close side where the external auxiliary light unit cannot illuminate. Here, if it is determined that it is on the close side, there is a high possibility that it will be useless even if the external auxiliary light means is turned on, so the process proceeds to step 106 in order to positively use the built-in auxiliary light means. On the other hand, in the case of the range ring position which can be illuminated by the external auxiliary light unit, step 1 is performed to perform AF by the external auxiliary light unit.
Proceed to 12. [Step 112] Here, AF is performed by illuminating the external auxiliary light unit. [Step 113] In the AF in Step 112, it is determined whether or not an image is found by the illumination of the external auxiliary light unit. If the image is found by this auxiliary light and the lens is driven, the process proceeds to Step 104 and the external When the image cannot be found due to the large blurring state by the illumination of the supplementary auxiliary light means, the prediction value cannot be calculated at the current position of the range ring, and therefore the range ring is moved and the process proceeds to step 114 to perform AF again. [Step 114] The distance ring is moved to the closest end for AF again. [Step 115] Here, AF is performed again by illumination of the built-in auxiliary light means. Then, go to step 104,
This operation ends.

As described above, when the illumination type auxiliary light is used instead of the pattern projection type,
By using the external auxiliary light unit and the built-in auxiliary light unit having different parallaxes at the distance ring position, it is possible to eliminate unnecessary auxiliary light illumination at a position where an image cannot be found.
It is possible to prevent unnecessary power consumption and speed up AF by eliminating unnecessary light emitting operation.

Further, by preferentially using the external auxiliary light means of a power source separate from the camera body, it is possible to prevent power consumption of the camera body side.

(Second Embodiment) In the first embodiment, the auxiliary light is of the illumination type, not the pattern projection, whereas the auxiliary light is the pattern projection. A description will be given below as a second embodiment.

First, the outline of the auxiliary light AF for pattern projection will be described with reference to FIG.

FIG. 8A is a picture of the finder screen. In this example, a case where there are three distance measuring points 801, 802 and 803 will be described. The AF sensors 801 and 803 are arranged vertically, and AF can be performed by a horizontal line pattern. The AF sensor 802 is horizontally arranged, and AF can be performed by a vertical line pattern.

Here, FIG. 8B shows an example of the auxiliary light pattern projected by the auxiliary light.

In FIG. 8B, the horizontal stripe pattern 804 corresponds to the AF sensor 801, and FIG. 8C shows the state of the image signal 807 from each pixel of the AF sensor 801. Correlation calculation is performed by the upper and lower image signals that form The vertical stripe pattern 805 corresponds to the AF sensor 802, and the state of the image signal 808 from each pixel of the AF sensor 802 is shown in FIG. 8C, and the correlation calculation is performed by the left and right image signals forming a pair. Done. The horizontal stripe pattern 806 corresponds to the AF sensor 803, and the state of the image signal 809 from each pixel of the AF sensor 803 is shown in FIG. 8C, and the correlation calculation is performed by the pair of upper and lower image signals. Done.

As described above, in the case of the auxiliary light for pattern projection, the auxiliary light AF is possible when the patterns projected on the AF sensor overlap, and in the case of FIG. The subject 506 is not focused because the light pattern is not reflected.

Therefore, in this embodiment, an efficient auxiliary light sequence is proposed by switching between the external auxiliary light means and the built-in auxiliary light means based on the distance measurement result without auxiliary light.

This embodiment will be described below with reference to the flowchart of FIG. [Step 902] First, AF without using auxiliary light is performed. [Step 903] As a result of the AF in step 902, it is determined whether or not auxiliary light is necessary. If not necessary, the process proceeds to step 904 to drive the lens by an amount based on the distance measurement in step 902. [Step 904] The distance ring of the lens 13 is driven by communicating with the lens control circuit 2 based on the data measured in step 902. Then, the process proceeds to step 905 to end this operation.

If auxiliary light is required in step 903, the process proceeds to step 906 to determine whether the distance measurement data in step 902 is a short distance. [Step 906] It is determined whether or not the distance measurement result of step 902 is a short distance at which the projection pattern of the external auxiliary light unit does not reflect. If the distance is so short that the projection pattern of the external auxiliary light unit does not reflect, , A by built-in auxiliary light means
In order to perform F, the process proceeds to step 907. [Step 907] AF using the built-in auxiliary light means is performed. [Step 908] If the prediction can be calculated by the AF using the built-in auxiliary light in step 907, the process proceeds to step 909 to drive the lens. If the calculation cannot be performed, the lens drive step 909 is skipped and the process proceeds to step 905. [Step 909] Above step 90
Based on the data measured at 7, the lens control circuit 2 is communicated with to drive the range ring of the lens 13. And step 9
The operation proceeds to 05 and ends this operation.

In step 908, if the projection pattern of the external auxiliary light unit has a sufficient distance for reflection,
In order to perform AF using the external auxiliary light, the process proceeds to step 910. [Step 910] AF is performed using an external auxiliary light unit. [Step 911] If the precession can be calculated by the AF using the external auxiliary light unit in the above step 910, the process proceeds to step 912 to drive the lens. If not, the lens drive step 912 is skipped and the process proceeds to step 905. move on. [Step 912] The lens control circuit 2 is communicated with the lens 13 based on the data measured in step 910.
Drive the range ring. Then proceed to step 905,
This operation ends.

As described above, when the pattern projection type auxiliary light is used, the external auxiliary light means and the built-in auxiliary light means having different parallaxes are selectively used based on the initial distance measurement data. By eliminating useless auxiliary light illumination at the non-reflecting position, useless power consumption is prevented, and AF speed is increased by eliminating useless light emitting operation.

According to each of the above embodiments, when the external strobe device having the auxiliary light means is attached to the camera having the auxiliary light means built-in, the built-in auxiliary light means has a parallax with respect to the optical axis. Although the number is small, the external auxiliary light means has a large parallax with respect to the optical axis. Based on the characteristics of the two auxiliary light means, effective use of the two auxiliary lights becomes possible, quick focusing, and unnecessary waste. AF by auxiliary light that does not consume battery energy will be realized.

(Correspondence between Invention and Embodiment) In this embodiment, the microcomputer 1 corresponds to the autofocus means and auxiliary light selecting means of the present invention, and the built-in auxiliary light drive circuit 15 and auxiliary light means 502a of the present invention. It corresponds to built-in auxiliary light means, and the strobe light emission control circuit 5 and auxiliary light means 503a correspond to the external auxiliary light means of the present invention.

The above is the correspondence relationship between each configuration of the embodiments and each configuration of the present invention, but the present invention is not limited to the configurations of these embodiments, and the functions or embodiments shown in the claims or the embodiments It goes without saying that any structure may be used as long as it can achieve the function of.

(Modification) In this embodiment, the distance ring position for focus adjustment is input, it is determined whether or not the subject is at a close range, and the built-in auxiliary light means and the external auxiliary light means are switched. However, it is also possible to obtain subject distance information and switch between the built-in auxiliary light means and the external auxiliary light means based on this information.

Further, in this embodiment, the external auxiliary light means is provided as an example in the external strobe device, but of course, it may be an independent accessory.

Although the present invention has been described as applied to a single-lens reflex camera, it can also be applied to a camera such as a video camera having a telephoto lens.

Furthermore, the present invention may be constructed by appropriately combining the above-described embodiments or their techniques.

[0057]

As described above, according to the present invention, the built-in auxiliary light means has a small parallax with respect to the photographing optical axis, but the external auxiliary light means has a large parallax with respect to the photographing optical axis. Then, the current subject distance information is obtained, and based on this, the built-in auxiliary light unit and the external auxiliary light unit are used properly.

Further, according to the present invention, when the auxiliary light is required at the time of auto-focusing, the built-in auxiliary light is provided if the focus position detecting means detects that the current focus position is on the short distance side. If it is detected that it is on the far side, the external auxiliary light means is selected as the auxiliary light means, that is, the current focus position is on the near side or the far side. The built-in auxiliary light unit and the external auxiliary light unit are selectively used depending on whether the above condition is satisfied.

Therefore, it is possible to quickly focus and prevent wasteful consumption of battery energy.

[Brief description of drawings]

FIG. 1 is a flowchart showing an operation of a main part of a camera according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a circuit configuration of a camera according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing an operation when a release operation of FIG. 2 is performed.

FIG. 4 is a flowchart showing details of the AF operation of FIG.

FIG. 5 is a diagram showing irradiation ranges of a built-in auxiliary light unit of the camera according to the first embodiment of the present invention and an auxiliary light unit on the external strobe device side.

FIG. 6 is a diagram showing an irradiation range of auxiliary light means on the external strobe device side of FIG.

7 is a diagram showing an irradiation range of auxiliary light means on the camera body side of FIG.

FIG. 8 is a diagram showing a relationship between auxiliary light units corresponding to multiple points and multiple distance measuring points according to a second embodiment of the present invention, and a state of an image signal used for correlation calculation at this time.

FIG. 9 is a flow chart showing a switching operation of built-in and external auxiliary light means in the second embodiment of the present invention.

[Explanation of symbols]

 1 Microcomputer 2 Lens control circuit 5 Strobe light emission control circuit 6 Focus detection circuit 14 External strobe device 15 Built-in auxiliary light drive circuit 501 Lens 502 Camera body 502a Built-in auxiliary light means 503 External strobe device 503a External auxiliary Light means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical indication G03B 15/05

Claims (3)

[Claims] 1. A camera having a built-in auxiliary light means for autofocus, wherein external auxiliary light means can be mounted, when auxiliary light is required during autofocus, based on current subject distance information, A camera provided with auxiliary light selecting means for selecting either the built-in auxiliary light means or the external auxiliary light means mounted on the camera as auxiliary light means. 2. A focus position detecting means for inputting a position of a distance ring for movably holding a lens in an optical axis direction and detecting a current focus position, and a built-in auxiliary light means for autofocusing. In a camera that can be equipped with a supplementary auxiliary light unit, when auxiliary light is required during autofocus, if the focus position detection unit detects that the current focus position is on the near side, The built-in auxiliary light means is selected as the auxiliary light means, and if the remote side is detected, the auxiliary light selecting means is provided for selecting the external auxiliary light means as the auxiliary light means. camera. 3. When the autofocus using the built-in auxiliary light means is impossible, the distance ring is moved to the far side, and the autofocus using the external auxiliary light means is performed. If the autofocus using the external auxiliary light means is impossible, the distance ring is moved to the short distance side, and the autofocus means for performing the autofocus using the built-in auxiliary light means is provided. The camera according to claim 2, which is characterized in that.