JP2001154084A - Range finder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a range finder, capable of highly accurately finding a range in accordance with the condition of an object or the state of a camera. SOLUTION: This range finder is provided with a pair of photoreceptive lenses 101a and 101b, a pair of line sensors 102a and 102b, or a pair of area sensors 107a and 107b for respectively converting a pair of object images formed by the photoreceptive lenses 101a and 101b to electrical signals according to light intensity, an integration control circuit 103 for executing the integral control of the pair of sensors, a CPU 105 for calculating the object distance based on the object image data outputted from the pair of sensors, at least one light-projecting means 106 for projecting range finding signal light to the object, and as for the range finder, light is projected while switching the form of the light projecting pattern, a light-projecting area and the wavelength of the projected light in accordance with the luminance distribution in a photographic screen, the attitude and setting of the camera, the distribution of reflected light by preliminary projection and the contrast of the object.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distance measuring apparatus, and more particularly, to a distance measuring apparatus which projects a signal light for distance measurement to measure a distance to a subject.

[0002]

2. Description of the Related Art Various types of distance measuring devices used for silver halide cameras, digital cameras, video cameras, and the like have been conventionally proposed. Various techniques such as a distance method are used.

[0003] Of these, passive type distance measuring devices are:
This is to detect a light beam reflected from a subject by irradiating auxiliary light by a light projecting unit.

On the other hand, a camera or the like is often equipped with a so-called zoom lens that can change the focal length of a photographing lens. In such a zoom lens, the range of a subject to be photographed is varied according to the focal length. Change.

If the passive type distance measuring device is applied to a camera having such a zoom lens or the like, an auxiliary light irradiation range within a photographing range changes.
As it is, it cannot be said that it is suitable for optimal distance measurement.

From such a viewpoint, Japanese Patent Application Laid-Open No. 9-25809
Japanese Patent Application Laid-Open No. 4 (1999) -1995 describes a distance measuring device in which the irradiation angle of the auxiliary light is changed according to the focal length of the photographing lens and the field magnification of the finder.

[0007]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 9-258.
The technique described in Japanese Patent Application Publication No. 094 has the advantage that the irradiation angle of the auxiliary light can be changed in accordance with the photographing range, but it is only in this case that the irradiation angle of the auxiliary light needs to be switched. Rather, the passive type distance measuring device described in the official gazette describes various other shooting conditions,
For example, switching cannot be performed according to the state of the camera, the condition of the subject, and the like.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a distance measuring apparatus capable of performing a highly accurate distance measurement according to a subject condition or a camera state.

[0009]

In order to achieve the above object, a distance measuring apparatus according to a first aspect of the present invention has a pair of light receiving lenses for forming a subject image, and an image formed by these light receiving lenses. A pair of line sensors that respectively convert the pair of subject images into electric signals according to light intensity, integration control means that performs integral control of the pair of line sensors, and subject image data output from the pair of line sensors. Computing means for computing data according to the subject distance based on the object condition, and at least one light projecting means for projecting a signal light for distance measurement to the subject, wherein the projecting condition is determined based on the subject condition or the state of the camera. It is configured to switch.

A distance measuring apparatus according to a second aspect of the present invention includes a pair of light receiving lenses for forming a subject image, and a pair of subject images formed by these light receiving lenses, each of which is provided with an electric signal according to light intensity. A pair of area sensors to convert to
Integral control means for performing integral control of the pair of area sensors; computing means for computing data corresponding to a subject distance based on subject image data output from the pair of area sensors; and a distance measurement signal for the subject. At least one light projecting means for projecting light, the light projecting means, when projecting the signal light for distance measurement, brightness distribution in the shooting screen, the attitude and setting of the camera, pre-lighting of Light projection is performed by switching at least one of the shape of the light projection pattern, the light projection range, and the wavelength of the projection light in accordance with at least one of the reflected light distribution and the contrast of the subject.

Further, a distance measuring apparatus according to a third aspect of the present invention is the distance measuring apparatus according to the first or second aspect of the present invention, wherein the stationary light removing means for removing the stationary light constantly entering the line sensor or the area sensor. And a function of integrating only the reflected light of the signal light from the subject.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 8 show a first embodiment of the present invention. FIG. 1 is a block diagram showing a configuration of a distance measuring device using (A) a line sensor and (B) an area sensor as light receiving elements. FIG. 2 shows (A) a plurality of LEs.
FIG. 3A is a block diagram showing the configuration of a light projecting device using D, and FIG. 3B is a block diagram showing the configuration of a light projecting device using a movable light-shielding mask for switching the light projecting range. Figure showing the viewfinder view when
(B) is a diagram showing subject image data when integrated only with stationary light; (C) is a diagram showing subject image data when signal light is projected onto the central portion of the main subject and integrated; FIG. FIG. 5 is a diagram showing a modification of the light projecting pattern of the signal light by the LED, and FIG. 5 is a diagram showing an example of switching the light projecting range of the light projecting means using the movable light-shielding mask.
(B) the center of the shooting screen, (C) the left side of the shooting screen,
FIG. 6D is a diagram showing the arrangement of light-shielding masks when projecting signal light on the right side of the image-capturing screen, respectively. FIG. FIG. 7 is a flowchart showing a distance measuring sequence of the distance measuring apparatus, and FIG. 8 is a flowchart showing a low luminance / low contrast determination process.

The distance measuring apparatus according to the first embodiment is shown in FIG.
(A) or as shown in FIG. 1 (B),
It is provided with a light projecting means 106 having a configuration as shown in FIG. 2 (A) or FIG. 2 (B). The distance measuring device is configured to detect a low-luminance region when a low-luminance region is detected in subject image data obtained by integrating only the stationary light without projecting the signal light by the light projecting unit 106. Then, signal light is projected from the light projecting means 106 to perform reintegration.

First, FIG. 1A shows the configuration of a distance measuring device when a line sensor is used as a light receiving element.

The distance measuring apparatus includes a pair of light receiving lenses 101a and 101b for forming a subject image, and converts the subject images formed by the light receiving lenses 101a and 101b into electric signals corresponding to the light intensity. Line sensors 102a and 102b for photoelectrically converting
An integration control circuit 103 as integration control means for controlling integration operations by the first and second sensors 02a and 102b, and an A / A for converting an analog electric signal obtained by photoelectrically converting the subject image output from the line sensors 102a and 102b into a digital electric signal. A D conversion circuit 104, a CPU 105 that outputs various control signals and performs various calculations including a subject distance calculation, and a light projecting unit 106 that projects a signal light for distance measurement to the subject. It is configured to have.

FIG. 1B shows a configuration of a distance measuring apparatus in which an area sensor is used as a light receiving element.

This distance measuring apparatus is constructed in substantially the same manner as the distance measuring apparatus shown in FIG. 1A, except that area sensors 107a and 107b are used as light receiving elements.

Next, FIG. 2A shows a case where a plurality of LEDs are used as a light source.
3 shows an example of the configuration of the light projecting means 106 in the case of using.

The light projecting means includes LEDs 112a, 112b, which will be described later, based on a light emission request from the CPU 105.
LED for driving 112c, 112d, 112e
A driving circuit 113 and 112a, 1 that are driven and controlled by the LED driving circuit 113 to generate signal light for distance measurement.
12b, 112c, 112d, and 112e, and their L
EDs 112a, 112b, 112c, 112d, 112
e, and a light projecting lens 111 for projecting the signal light for distance measurement emitted from e toward the subject.

FIG. 2B shows an example of the configuration of the light projecting means 106 when a movable light shielding mask is used for switching the light projecting range.

The light projecting means includes an LED driving circuit 125 for driving an LED 124 described later based on a light emission request from the CPU 105, and an LED driving circuit 125
That is driven and controlled by the controller to generate signal light for distance measurement
D124, and a pattern mask 123 formed by using printing or the like, which defines a projection pattern of the signal light for distance measurement by partially restricting a transmission range of the signal light emitted from the LED 124, This pattern mask 12
The light shielding mask 12 for switching the projection range of the pattern signal light for distance measurement by movably shielding a part of the light shielding mask 12.
2a, 122b; a light-shielding mask driving circuit 126 for controlling the positions of these light-shielding masks 122a, 122b in response to a request from the CPU 105;
And a light projecting lens 121 for projecting the distance-measuring pattern signal light, which is emitted from the light-shielding masks 122a and 122b and is not shielded by the light-shielding masks 122a and 122b, toward the subject.

Next, with the distance measuring device having the above-described configuration,
For example, consider the case of performing distance measurement of a backlight scene as shown in FIG.

FIG. 3A is a view showing a scene in which a person who is a main subject has a low luminance with respect to the background due to backlight, and reference numerals 131a, 131b, 131c, 131
d and 131e are, for example, those shown in FIG.
(A) LEDs 112a, 112b, 112c, 112
The light projection ranges of d and 112e are shown, respectively.

FIG. 3B shows an example of subject image data 132 obtained when the scene as shown in FIG. 3A is integrated by a light receiving element using only stationary light. The light receiving element includes a plurality of low luminance portion detection blocks 133, 134, 135 and 135 as shown in FIG.
It is divided into 136 and 137.

In the case shown in FIG. 3B, for example, block 1 corresponding to the part of the person who is the main subject
34 are low-luminance detection blocks 133, 134, and 13
5,136,137, it is determined that the luminance is low.

Next, FIG. 3 (C) shows that the LED 112b corresponding to the block 134 emits light and the
An example of subject image data 138 when a signal light is projected on 31b and integrated by a light receiving element is shown.

In the case of the example shown in FIG. 3B, the reintegration is performed as shown in FIG. 3C. Subject image data 138 obtained by the reintegration
Calculation region 1 so as to include the region where the signal light is projected.
39 is set, and subject distance data is calculated by performing a predetermined correlation operation or interpolation operation using the data in the operation area 139.

In the light projecting means 106 having the structure shown in FIG.
The light projected by b, 112c, 112d, and 112e is not limited to spot light. For example, a light emitting pattern of a plurality of slits as shown in FIG. 141a, 141b, 141
c, 141d, and 141e may be projected.

Although five LEDs are provided in the above description,
Of course, the present invention is not limited to this number, and a smaller number or a larger number may be arranged.

Further, the light projecting means 106 is provided in the above-mentioned FIG.
LED 124 and pattern mask 1 as shown in FIG.
23 and a structure using the movable light shielding masks 122a and 122b.

As shown in FIG. 5, the switching of the light projecting area by the light projecting means 106 having such a configuration is performed as shown in FIG.
This is performed by changing the positions of 22a and 122b.
5A and 5B show an example of switching the light emitting range of the light emitting means using a movable light shielding mask. FIG. 5A shows a case where the signal light is projected over the entire area of the photographing screen. 5C is a case where the signal light is projected on the center of the shooting screen, FIG. 5C is a case where the signal light is projected on the left side of the shooting screen, and FIG. 5D is a case where the signal light is projected on the right side of the shooting screen. When projecting, light shielding mask 1
The arrangement of 22a and 122b is shown, respectively.

FIG. 6 shows a scene in which a person who is a main subject in backlight is located slightly to the left in the screen, and an example of a projection range and a pattern in this backlight scene.

In such a backlight scene, similarly to the above, integration is performed with only normal light, and a block having a low luminance is detected from the result, and a light having a pattern corresponding to the block, for example, a pattern 151 is shown. To project such light. In this example, the movable light-shielding masks 122a and 122b are moved to the positions shown in FIG. 5C, for example, and the LED 124 emits light to obtain the projection light of the pattern 151.

In the above description, the projection light pattern is determined by using the pattern mask 123 and the movable light-shielding masks 122a and 122b. However, the present invention is not limited to this. The light projection area may be switched by electrically switching the pattern between the light transmitting part and the light shielding part.

The detection of the low luminance area may be performed by other image processing methods such as photometric data by multi-segment photometry or binarization processing.

As a configuration of the distance measuring apparatus of the first embodiment, for example, FIG. 18 (A) and FIG.
As shown in (1), a circuit having a stationary light removal circuit 408 for integrating only the reflected light of the signal light from the subject may be used. By using the distance measuring device having such a configuration, the influence of the contrast state of the background of the main subject and the influence of the light source can be removed, so that more accurate distance measurement can be performed.

Next, a distance measuring sequence of the distance measuring apparatus will be described with reference to FIG.

When this process is started, a monitor area for steady light integration is set (S101). The monitor area is a sensor range in which the integration control circuit 103 outputs the average value of the sensor data in the area and the integration amount of the sensor with the fastest integration speed as monitor data in order to control the integration. The monitor area is usually set to be the entire sensor area or a relatively large area.

Next, the sensor sensitivity for steady light integration is set based on the photometric data, the pre-integration result, and the like (S10).
2). The sensor sensitivity may be switched between only two steps of low sensitivity / high sensitivity, or may be switched over more steps.

Then, steady light integration is performed on the monitor area set in step S101 according to the sensor sensitivity set in step S102 (S10).
3). The control of the integration at this time is performed by detecting whether the monitor data has reached a predetermined value or by determining whether a predetermined time has elapsed from the start of the integration.

Next, the subject image signal obtained by the steady light integration in step S103 is subjected to A / D conversion by the A / D conversion circuit 104.
The data is converted and read into the RAM in the CPU 105 as sensor data (S104). At this time, the maximum value MAX of the sensor data (sensor data obtained by integrating the darkest part)
Is also detected.

It is determined whether or not the sensor data obtained by the steady light integration in step S103 has a low luminance and low contrast portion (S105). As shown in FIG. 3B, this determination is made by dividing the sensor area into a plurality of low-luminance part detection blocks 133, 134, 145, and
It is divided into 136 and 137, and the judgment is made for each block.

If the result of determination in step S105 is that all blocks have low contrast, the flow proceeds to step S111 to be described later, while if there is a block that does not have low contrast, the flow proceeds to subsequent step S107 (S106). .

Then, a predetermined calculation area for calculating the distance measurement data is set (S107). Note that the calculation area is usually set to the same area as the divided block in the low luminance / low contrast determination in step S105, but may be set to a different area.

A predetermined correlation operation, interpolation operation, or the like is performed for each calculation region set in step S107, and a pair of light receiving lenses 101a and 101b are used to form a pair of sensors 102.
A shift amount (phase difference) between a pair of subject images formed on a, 102b or 107a, 107b is obtained, and distance measurement data is calculated by a known triangulation principle (S).
108).

Next, it is determined whether or not the maximum value MAX of the sensor data detected in step S104 is larger than a predetermined value (S109). If it is larger than the predetermined value, the process proceeds to the next step S110. If it is smaller, it is determined that there is no low-luminance portion in the sensor data, and the process proceeds to step S116 described later.

Subsequently, based on the result of the determination in step S105, it is determined whether or not there is a low-brightness and low-contrast portion (S110). If it is determined that there is a portion, the process proceeds to the next step S111. On the other hand, if it is determined that there is none, the process proceeds to step S116 described below.

Further, based on the result of the determination in step S105, a monitor area for auxiliary light integration is set (S105).
111). That is, for example, in the distance measurement of a backlight scene as shown in FIG. 3A, as shown in FIG. 3B, the image of the person who is the main subject has low luminance and low contrast in the steady light integration. If the sensor data 132 is obtained, a monitor area is set in the low luminance / low contrast determination block 134.

Next, signal light is projected by the light projecting means 106 into a range corresponding to the block determined to have low brightness and low contrast in step S105, and the auxiliary light is projected in the monitor area set in step S111. Integration is performed (S112). Specifically, in a backlight scene as shown in FIG. 3A, light is projected on the light projecting area 131b. The sensor sensitivity at this time is set according to the amount of reflected signal light at the beginning of integration. The control of integration is the same as in step S103.

The A / D conversion circuit 104 performs A / D conversion of the subject image signal obtained by integrating the auxiliary light in step S112, and reads the data as sensor data into the RAM in the CPU 105 (S113). The sensor data to be read at this time may be data of all sensors, or may be the next step S11.
Only the sensor data of the calculation area set in 4 may be used.

Then, a calculation area for calculating the distance measurement data is set (S114). The calculation area set at this time may be the same as the block determined to have low contrast, or may be set to a wider area or a plurality of areas including a low-brightness / low-contrast block.

A predetermined correlation operation, interpolation operation, or the like is performed in the operation area set in step S114, and a pair of light receiving lenses 101a and 101b are used to perform a pair of sensor operations.
A shift amount (phase difference) between a pair of subject images formed on a, 102b or 107a, 107b is calculated, and distance measurement data is calculated by a known triangulation principle (S1).
15).

Then, from the distance measurement data obtained in steps S108 and S115, the distance measurement data to be used for photographing is selected by closest selection or the like (S11).
6), this process ends.

Next, with reference to FIG.
The details of the low-brightness / low-contrast determination process performed in step S05 will be described.

When this processing is started, first, a low luminance
The number of determination blocks for performing low contrast determination is set (S121), and the number of the block for which determination is performed is set (S122).

Further, the minimum value min and the maximum value max of the sensor data in the block are initialized (S123). Specifically, for example, when the sensor data is 8-bit data, min = FFH and max = 00H (the symbol H indicates a hexadecimal number) are set.

Thereafter, the RAM address of the next sensor data is set (S124). In the case of the first time, the head RAM address of the sensor data of the block to be determined is set.

Then, the sensor data of the currently set RAM address is read (S125).

It is determined whether or not the sensor data read in step S125 is larger than the maximum value max of the sensor data in the currently set determination block (S126). If the sensor data is larger, the flow advances to the next step S127. If it is smaller, the process proceeds to step S128 described later.

If it is determined in step S126 that the value is large, the current sensor data is stored in the maximum value max (S127).

Further, it is determined whether or not the sensor data read in step S125 is smaller than the minimum value min of the sensor data in the currently set determination block (S128). S129
If it is larger, the process proceeds to step S130 described later.

If it is determined in step S128 that the value is small, the current sensor data is stored in the minimum value min (S129).

Next, it is determined whether the detection of the maximum value and the detection of the minimum value have been completed for all the sensors in the currently set determination block (S130). If not, the flow returns to step S124 to return to the above. The process is repeated, and if it has been completed, the process proceeds to step S13.
Proceed to 1.

Then, low contrast determination is performed for the currently set determination block (S131).
That is, if the difference between the maximum value max and the minimum value min of the sensor data in the block is smaller than a predetermined value, it is determined that the contrast is low, and the process proceeds to the next step S132. The process proceeds to step S134 to be described later.

If it is determined in step 131 that the contrast is low, a low luminance determination is further performed for the currently set determination block (S132).
This low luminance determination is made based on whether or not the minimum value min of the sensor data in the block is larger than a predetermined value. If it is larger, it is determined that the luminance is low, and the next step S1 is performed.
The process advances to step S134, where it is determined that the brightness is not low if the brightness is small, and the process advances to step S134 described later.

Note that, here, the minimum value min
However, instead of the minimum value min, an average value of the sensor data in the block may be used.

Then, the number of the currently set judgment block is stored as data of a low-luminance / low-contrast block (S133).

Thereafter, it is determined whether or not the low luminance / low contrast determination has been completed for all the determination blocks (S134).
Returning to step 122, the above-described processing is repeated. If the processing has been completed, the processing returns to the processing in FIG.

According to the first embodiment, since the low-luminance area is detected and the signal light is projected,
It is possible to efficiently illuminate only the area where the auxiliary light is required.

FIGS. 9 to 11 show a second embodiment of the present invention. FIG. 9 is a block diagram showing the configuration of the light projecting means of the distance measuring device, and FIG. 10 is a signal for each distance measuring. A diagram showing a light projection range and a pattern example into a shooting screen by a light source,
FIG. 11 is a flowchart showing a distance measuring sequence of the distance measuring device.

In the second embodiment, the first
The description of the same parts as those of the embodiment is omitted,
Only the differences will be mainly described.

The distance measuring apparatus according to the present embodiment is designed to switch the light emitting range, the light source, and the like of the signal light for distance measurement in accordance with the photographing mode of the camera set by the photographer.

First, the configuration of the distance measuring device is almost the same as that shown in FIGS. 1A and 1B of the first embodiment, but the light projecting means 106 As shown in FIG. 9, it is configured to have various light sources.

That is, the light projecting means is an auxiliary light source for performing exposure in photographing, and charges the strobe 201 which is also used as a signal light source for a normal distance measurement, and a light emitting capacitor of the strobe 201. Control circuit 202 for controlling the light emission of the strobe 201
And infrared LEDs 204a, 204b, 204c, 204d, which will be described later, based on a light emission request from the CPU 105.
Infrared LED drive circuit 205 for driving 204e
And an infrared LED 204 driven and controlled by the infrared LED drive circuit 205 to generate a signal light for distance measurement in a portrait mode, a night view mode, or a strobe off mode.
a, 204b, 204c, 204d, 204e and these infrared LEDs 204a, 204b, 204c, 204
d, 204e, and a light projecting lens 203 for projecting a signal light for distance measurement emitted toward the subject, and the CPU 105
A self-LED driving circuit 207 for driving a self-LED 206 described later based on a command from the microcomputer, and a self-timer display light source that emits light by being driven by the self-LED driving circuit 207 and is used as a signal light source in the macro mode And a self LED 206 to be used.

This distance measuring device switches the projection range of the signal light for distance measurement, the light source, and the like in accordance with the photographing mode of the camera. Some examples thereof are shown in FIG. Will be explained.

For example, in the normal mode, the strobe 2
01 is emitted, and as shown in FIG. 10A, the signal light is projected onto a light projecting range 212 covering substantially the entire area of the photographing screen 211.

In the spot mode, the infrared LE
D204c is caused to emit light, and the signal light is projected onto a relatively narrow light projecting range 213 at the center of the photographing screen 211 as shown in FIG.

In the portrait mode or the night scene mode, when a person is a subject, the person is not dazzled or the amount of charge of a capacitor storing electric charge for strobe light emission is not reduced. The infrared LEDs 204a, 204b, 204c, 204d, 20
4e to emit light, and as shown in FIG. 10 (C), each light projecting range 214a, 214b, 214 in the photographing screen 211.
Signal light is projected on c, 214d, 214e.

In the strobe off mode, the above strobe 2
01 cannot be used, and the infrared LE shown in FIG.
D204a, 204b, 204c, 204d, 204e
Is emitted, and the signal light is projected as shown in FIG.

Also, in the macro mode, if the signal light quantity is too large, the integration control becomes complicated, and it is desirable that the signal light projection angle be a wide angle because of the occurrence of parallax in close-up photography. Then, the self LED 206 for displaying the self-timer is caused to emit light, and a signal light is projected on the entire photographing screen 211 as shown in FIG.

On the other hand, in the landscape mode, since the photographing scene is a distant view and the effect of projecting the signal light cannot be obtained,
Neither light source emits light.

In the above description, the visible light source is the one shown in FIG.
Although the strobe 201 as shown in FIG. 2 is used, a configuration using visible light LEDs as shown in FIGS. 2A and 2B may be used instead. Further, the light source in the spot mode may be performed by the visible light source.

Further, a plurality of infrared LEs as shown in FIG.
D204a, 204b, 204c, 204d, 204e
10D and FIG. 10 by using a configuration using light-shielding masks 122a and 122b and a pattern mask 123 as shown in FIG.
The switching of the projection range as shown in FIG.

FIG. 10D shows the infrared LED arrays 204a, 204b,
FIG. 2B instead of 204c, 204d, and 204e
Light-shielding masks 122a, 122b and pattern mask 12
3 shows a light projection range and a pattern 215 on the photographing screen 211 in a configuration using No. 3.

FIG. 10E shows the infrared LED arrays 204a, 204b, 204c, and 20 of FIG. 9 in, for example, the portrait mode, the night scene mode, and the strobe off mode.
Instead of 4d and 204e, the light-shielding mask 1 shown in FIG.
Projection range and pattern 21 on photographing screen 211 in a configuration using pattern masks 22a and 122b
6 is shown.

FIG. 10F shows, for example, a projection range and a pattern 217 on the photographing screen 211 when a pattern is added to the projection light by the self LED 206 in the macro mode.

Next, a distance measuring sequence including the switching of the distance measuring signal light according to the photographing mode of the camera will be described with reference to FIG.

When this process is started, step S
In the same manner as described in 101, a monitor area for steady light integration is set (S201).

Next, it is determined whether or not the shooting mode of the camera is the landscape mode (S202). If the mode is the landscape mode, the process proceeds to step S219 described later. If the mode is not the landscape mode, the process proceeds to the next step S203.

Then, it is determined whether or not the photometry data has a luminance lower than a predetermined value (S203). Here, if the brightness is low, the process proceeds to the next step S204. If the brightness is not low, the process proceeds to a step S219 described later. This luminance determination may be performed based on the integration time in step S220 described later.

Subsequently, it is determined whether the shooting mode of the camera is the macro mode (S204). If the mode is the macro mode, the process proceeds to step S215 described later. If the mode is not the macro mode, the process proceeds to step S215.
Proceed to 205.

Next, it is determined whether or not the shooting mode of the camera is the spot mode (S205). If the mode is the spot mode, the process proceeds to step S216 described later. If the mode is not the spot mode, the process proceeds to step S206.

It is determined whether the shooting mode of the camera is the portrait mode (S206). If the mode is the portrait mode, the process proceeds to step S217 described below. If the mode is not the portrait mode, the process proceeds to step S207.

It is determined whether the shooting mode of the camera is the night scene mode (S207). If the mode is the night view mode, the process proceeds to step S217 described below. If the mode is not the night view mode, the process proceeds to step S208.

It is determined whether or not the photographing mode of the camera is the strobe off mode (S208). If the mode is the flash-off mode, the process proceeds to step S217 described later. If the mode is not the flash-off mode, the process proceeds to step S209.

Then, signal light is projected by the strobe 201, and integration is performed in the monitor area set in the step S201 (S209). Note that the monitor area may be set to an area different from the area set in step S201. The control of integration at this time is the same as in step S220 described later.

Next, the subject image signal obtained by each integration is converted into the above A
A / D conversion is performed by the / D conversion circuit 104, and the data is read into the RAM in the CPU 105 as sensor data (S210).

Thereafter, a predetermined calculation area for calculating the distance measurement data is set (S211). This calculation area is usually, for example, as shown in FIG.
The low-luminance portion detection blocks 133, 134, and 135 shown in FIG.
Set multiple areas as shown. In the spot mode, a block 13 at the center of the shooting screen is used as a calculation area.
Set 5 only.

A predetermined correlation operation, interpolation operation, or the like is performed for each operation region set in step S211, and the amount of shift (phase difference) of the pair of subject images formed on the pair of sensors by the pair of light receiving lenses. ) Is calculated, and the distance measurement data is calculated according to the known principle of triangulation (S212).

Based on the result of the calculation in step S212, it is determined whether or not distance measurement was impossible in all the areas set in step S211 (S213). If the distance cannot be measured, the process proceeds to step S214. If the distance cannot be measured, the process proceeds to step S214 described later.
Proceed to 227.

If the distance cannot be measured in step S213, triangulation cannot be performed to measure the distance based on the shift amount of the normal pair of subject images. Distance (light amount AF) is performed (S21)
4). Here, when calculating the distance measurement data, the data is corrected according to the light source that has projected the signal light so that the same distance measurement data is obtained if the object distance and the object reflectance are the same.

If the mode is the macro mode in step S204, signal light is projected by the self-LED 206, and integration is performed in the monitor area set in step S201 (S215). This monitor area
The area may be set to an area different from the area set in step S201. The control of integration at this time is the same as in step S220 described later.

In the case of the spot mode in the step S205, the signal light is projected from the infrared LED 204c, the monitor area is set at the center of the photographing screen, and the integration is performed (S216). The control of integration at this time is the same as step S220 described later.

When the portrait mode is set in step S206, the night scene mode is set in step S207, and the strobe off mode is set in step S208, the infrared LEDs 204a and 2 are set.
Signal light is projected from the elements 04b, 204c, 204d, and 204e, and integration is performed in the monitor area set in step S201 (S217). This monitor area may be set to an area different from the area set in step S201. The control of integration at this time is the same as in step S220 described later.

Then, in the integration in step S216 or S217, it is determined whether or not the amount of signal light reflected from the subject is smaller than a predetermined amount based on the integration speed, integration time, and the like (S218). If the value is smaller, the process proceeds to step S209. If the value is larger, the process proceeds to step S210.

If the scene mode is set in step S202, and if the brightness is low in step S203, the sensor sensitivity for steady light integration is set based on photometric data, pre-integration results, and the like (S21).
9).

Then, for the monitor area set in step S201, steady light integration is performed based on the sensor sensitivity set in step S219 (S22).
0). The control of the integration at this time is performed by detecting whether the monitor data has reached a predetermined value or by determining whether a predetermined time has elapsed from the start of the integration.

The A / D conversion circuit 104 performs A / D conversion of the subject image signal obtained by the steady light integration in step S220 (S221), and reads the data as sensor data into the RAM in the CPU 105.

Thereafter, a predetermined calculation area for calculating the distance measurement data is set (S222). This calculation area is usually, for example, like the low-luminance part detection blocks 133, 134, and 135 shown in FIG.
Set multiple areas.

A predetermined correlation operation, interpolation operation, or the like is performed for each calculation region set in step S222, and a shift amount (phase difference) of a pair of subject images formed on a pair of sensors by a pair of light receiving lenses. ) Is calculated, and the distance measurement data is calculated according to the known principle of triangulation (S223).

On the basis of the result of the calculation in step S223, it is determined whether or not distance measurement was impossible in all the areas set in step S222 (S224). If the distance cannot be measured, the process proceeds to step S225. If the distance cannot be measured, the process proceeds to step S225 described later.
Proceed to 227.

Then, it is determined whether or not the shooting mode of the camera is the landscape mode (S225). Here, in the case of the landscape mode, the process proceeds to the subsequent step S226.
If the mode is not the landscape mode, the process proceeds to step S204.

If the mode is the landscape mode in step S225, infinite data is set as the distance measurement data (S226).

The above step S213 or step S2
If it is determined in step S24 that distance measurement cannot be performed, distance measurement data to be used for photographing is selected from the distance measurement data obtained in steps S212 and S223 by closest selection or the like (S227).

Thus, the above steps S214 and S22
6. When any one of S227 is completed, this processing ends.

It should be noted that also in the second embodiment, the distance measuring device may be configured to have a stationary light removing circuit 408 as shown in FIGS. 18A and 18B described later. This is the same as the first embodiment described above.

According to the second embodiment, substantially the same effects as those of the first embodiment can be obtained, and optimum light emission can be performed according to the photographing mode.
Without affecting the subject or camera condition at the time of shooting,
High-precision distance measurement can be performed.

FIGS. 12 to 17 show a third embodiment of the present invention. FIG. 12 is a block diagram showing a configuration of a light projecting means of a distance measuring apparatus, and FIG. 13 is a configuration using a line sensor. FIG. 14 is a diagram showing an example of a pattern printed on a pattern mask, and FIG. 15 is a diagram showing a projection pattern of signal light for distance measurement by a pattern mask onto a shooting screen. FIG. 16 is a block diagram showing a configuration example of the camera posture detecting means, and FIG. 17 is a flowchart showing a distance measuring sequence of the distance measuring device.

In the third embodiment, a description of the same parts as those in the first and second embodiments will be omitted, and only different points will be mainly described.

In the third embodiment, in the distance measuring apparatus having the configuration using the area sensors 107a and 107b as shown in FIG. 1B, the light projecting means 106 is configured as shown in FIG. That is, the camera posture detecting means 306
That detects whether the camera is vertical or horizontal at the time of shooting, and switches the projection pattern of the signal light for distance measurement according to the detected camera attitude. It is.

It is also possible to configure a distance measuring device using a line sensor as the light receiving element. In this case, however, it is necessary to use a device capable of measuring distance in two directions, vertical and horizontal.

As an example of such a light receiving element, as shown in FIG. 13, a formed image of a subject is photoelectrically converted into an electric signal corresponding to the light intensity thereof. Line sensors 312 arranged in
a, 312b, 312c, 312d, and a light receiving lens 311 for forming a subject image on each of the line sensors 312a, 312b, 312c, 312d.
a, 311b, 311c, and 311d.

Next, as shown in FIG. 12, the light projecting means of the distance measuring apparatus of the third embodiment includes an LED driving circuit 304 for driving an LED 303 described later based on a light emission request from the CPU 105. , This LED drive circuit 30
L that is driven and controlled by the control unit 4 to generate signal light for distance measurement
When the camera is in a horizontal position, the ED 303 defines a projection pattern of signal light for distance measurement by partially restricting a transmission range of signal light emitted from the LED 303. When the posture of the pattern mask 302a and the camera is in the vertical position, the transmission range of the signal light emitted from the LED 303 is partially restricted to project the signal light for distance measurement. The pattern mask 302b defines a pattern and is formed by printing or the like.
Alternatively, a light projecting lens 301 for projecting a pattern signal light for distance measurement that has passed through a pattern mask 302b to a subject.
And whether the posture of the camera is vertical or horizontal,
A camera posture detecting means 306 for outputting to the PU 105, and a pattern mask driving circuit 305 for moving the pattern masks 302a and 302b in accordance with the posture of the camera detected by the camera posture detecting means 306 to switch the light projection pattern. It is configured to have.

Generally, there is a high probability that the boundary of the contrast of the subject exists in a direction perpendicular to the ground, such as a pillar or a window frame. Therefore, regardless of whether the camera attitude at the time of shooting is vertical or horizontal, it is preferable to project a light projection pattern having a contrast edge in the vertical direction in the shooting screen.

The pattern mask 302 thus configured
Examples of a and 302b will be described with reference to FIG.

As described above, the pattern mask 302a is formed by printing the projection pattern of the signal light for distance measurement when the camera is in the horizontal position, and includes a plurality of vertical slits for transmitting the light. Is configured.

The other pattern mask 302b is formed by printing a projection pattern of signal light for distance measurement when the camera is in a vertical position, and has a plurality of horizontal slits for transmitting light. .

The pattern masks 302a and 302b having such two types of patterns are moved by the pattern mask drive circuit 305 in accordance with the vertical and horizontal directions of the camera detected by the camera attitude detecting means 306, and the light projection patterns Is switched.

Thus, when the camera is in the horizontal position, the pattern mask 302a is used to
15B is projected onto the photographing screen 321. On the other hand, when the posture of the camera is vertical, the light projection pattern 322b as shown in FIG. Is projected in the photographing screen 321 (the figure is shown in a horizontal position).

The direction in which the data of the correlation calculation for obtaining the shift amount (phase difference) between the pair of subject images formed on the pair of sensors by the pair of light receiving lenses is also adjusted in accordance with the switching of the projection pattern. It is switched according to the orientation of the posture.

In the above description, two types of pattern masks 3 are used.
Although the configuration is such that the projection light pattern is switched using 02a and 302b, the present invention is not limited to this. For example, the display pattern, that is, the pattern between the light-transmitting portion and the light-shielding portion, is electrically switched using a transmissive liquid crystal. , The light projection pattern may be switched.

Further, instead of pattern light projection using a mask, the direction in which light is emitted may be switched using an LED array arranged in two directions, vertical and horizontal.

Further, the camera posture detecting means 306
For example, it is configured as shown in FIG.

The camera posture detecting means 306 has a mercury switch 331 whose output switches according to the posture of the camera. In this mercury switch 331, for example, mercury 332 is sealed in a glass tube formed in a T shape, and a pair of terminals is attached to each of three ends of the glass tube having a T shape. . In such a configuration, when the posture of the camera changes, the mercury 332 contained therein moves by gravity and comes to a position in contact with the lowest terminal of the three pairs of terminals. As a result, the paired terminals conduct.

The vertical / horizontal detection circuit 333 is connected to the mercury switch 331, and detects which of the three terminal pairs is conducting, thereby detecting the direction in which gravity acts, that is, The downward direction can be detected, and the posture of the camera can be detected.

The attitude of the camera detected by the vertical / horizontal detection circuit 333 is output to the CPU 105.

The structure of the camera posture detecting means 306 shown in FIG. 16 is an example, and is not limited to this, and a detecting device having another structure may be used.

Next, a distance measuring sequence of the distance measuring apparatus will be described with reference to FIG.

When the operation is started, first, it is determined whether or not the photometric data has a luminance lower than a predetermined value (S30).
1). If the brightness is low here, step S described later
The process proceeds to step S309, and if not, the process proceeds to the next step S302. Here, instead of determining whether or not the luminance is low, the luminance may be determined based on the integration time in step S304 described later.

Subsequently, a monitor area for integration of the steady light is set in the same manner as described in step S101 (S302).

Then, based on the photometric data, the pre-integration result, and the like, the sensor sensitivity for the steady light integration is set (S30).
3).

For the monitor area set in step S302, steady light integration is performed based on the sensor sensitivity set in step S303 (S304). The control of the integration at this time is performed by detecting whether the monitor data has reached a predetermined value or by determining whether a predetermined time has elapsed from the start of the integration.

The A / D conversion circuit 104 performs A / D conversion on the subject image signal obtained by the steady light integration in step S304, and reads the data as sensor data into the RAM in the CPU 105 (S305).

Then, a predetermined calculation area for calculating the distance measurement data is set (S306). This calculation area is usually, for example, like the low-luminance part detection blocks 133, 134, and 135 shown in FIG.
Set multiple areas.

A predetermined correlation operation, interpolation operation, or the like is performed for each of the calculation regions set in step S306, and a shift amount (phase difference) of a pair of subject images formed on a pair of sensors by a pair of light receiving lenses. ) Is calculated, and the distance measurement data is calculated according to the known principle of triangulation (S307).

On the basis of the result of the calculation in step S307, it is determined whether or not distance measurement was impossible in all the areas set in step S306 (S308). If the distance cannot be measured, the process proceeds to step S309,
On the other hand, if the distance measurement is not possible, the process proceeds to step S316.

Subsequently, it is determined from the output of the camera posture detecting means 306 whether the camera posture is vertical or horizontal (S309). Here, if the posture of the camera is horizontal, the process proceeds to the subsequent step S310, while if it is vertical, the process proceeds to step S317 described later.

If it is determined in step S309 that the camera is in the horizontal position, a monitor area for horizontal position is set (S310). In this case, the direction is set to the direction in which the light projection patterns for the horizontal position are arranged except for the upper and lower portions of the shooting screen when the camera is in the horizontal position.

Then, the pattern mask drive circuit 30
5, the pattern mask 302a for the horizontal position is set (S311).

On the other hand, if it is determined in step S309 that the camera is in the vertical position, the monitor area for the vertical position is set (S317). Here, the vertical direction of the projection pattern is set except for the upper and lower portions of the shooting screen when the camera is in the vertical position.

Then, the pattern mask driving circuit 30
5, the pattern mask 302b for the vertical position is set (S318).

Step S311 or step S3
When the pattern mask is set at 18, the above L
The ED 303 emits light to project the pattern of the pattern mask 302a or 302b, and performs integration in the monitor area set in step S310 (S312). Note that the integration control at this time is performed in step S30 described above.
Same as 4.

A / D conversion is performed by the A / D conversion circuit 104 on the subject image signal obtained by the pattern light integration in step S312, and is read into the RAM in the CPU 105 as sensor data (S313).

Then, a predetermined calculation area for calculating the distance measurement data is set (S314). This calculation area is usually, for example, like the low-luminance part detection blocks 133, 134, and 135 shown in FIG.
Set multiple areas.

A predetermined correlation operation, interpolation operation, or the like is performed for each operation area set in step S314, and the shift amount (phase difference) of the pair of subject images formed on the pair of sensors by the pair of light receiving lenses. ) Is calculated, and distance measurement data is calculated by a known triangulation principle (S315).

Steps S307 and S315
From the distance measurement data obtained in step (3), the distance measurement data to be used for photographing is selected by closest selection or the like (S316), and this processing ends.

As a configuration of the distance measuring apparatus of the third embodiment, as shown in FIG. 18B described later, a stationary light removing circuit 408 for integrating only the reflected light of the signal light from the subject. May be used. By using the distance measuring device having such a configuration, the influence of the contrast state of the background of the main subject and the influence of the light source can be removed, so that more accurate distance measurement can be performed.

According to the third embodiment, almost the same effects as those of the first and second embodiments can be obtained, and the projection pattern of the signal light for distance measurement according to the attitude of the camera. , High-accuracy distance measurement can be performed regardless of the attitude of the camera.

FIGS. 18 to 22 show a fourth embodiment of the present invention. FIG.
FIG. 19 is a block diagram showing a configuration of a distance measuring device using a line sensor and (B) an area sensor. FIG. 19 is a diagram showing a configuration of light projecting means of the distance measuring device. FIG. 20 is a photographing scene and a subject image relating to the photographing scene. FIG. 21 is a flowchart showing an example of data, FIG. 21 is a flowchart showing a distance measuring sequence of the distance measuring apparatus, and FIG. 22 is a flowchart showing processing of main subject determination.

In the fourth embodiment, the first
Therefore, description of the same parts as those of the third embodiment will be omitted, and only different points will be mainly described.

In the fourth embodiment, as shown in FIGS. 18A and 18B, a stationary light removal circuit 408 for integrating only the reflected light of the signal light for distance measurement from a subject. In the distance measuring apparatus having the configuration shown in FIG. 19 and the light projecting means 406 having the configuration shown in FIG. 19, an area having a large amount of reflected light is detected from the reflected light distribution of the signal light at the time of pre-projection integration, and The main subject is determined to be in the area where the main subject exists, and signal light is projected onto the detection area to perform main light integration.

First, FIG. 18A shows the configuration of a distance measuring device when a line sensor is used as a light receiving element.

This distance measuring device includes a pair of light receiving lenses 401a and 401b for forming a subject image, and converts the subject images formed by the light receiving lenses 401a and 401b into electric signals corresponding to the light intensity. Line sensors 402a and 402b for photoelectrically converting
An integration control circuit 403 as integration control means for controlling the integration operation by the first and second sensors 02a and 402b, and an A / A for converting an analog electric signal obtained by photoelectrically converting the subject image output from the line sensors 402a and 402b into a digital electric signal. A D conversion circuit 404 and a CPU that outputs various control signals and performs various calculations including subject distance calculation
105, light projecting means 406 for projecting the signal light for distance measurement to the object, and projecting the signal light for distance measurement in order to integrate only the reflected light from the object due to the signal light for distance measurement. Light removal circuit 4 for removing the steady light component when performing integration
08.

FIG. 18B shows the configuration of a distance measuring device in the case where an area sensor is used as a light receiving element.

This distance measuring apparatus is constructed in substantially the same manner as the distance measuring apparatus shown in FIG. 18A, except that area sensors 407a and 407b are used as light receiving elements.

FIG. 19 shows an example of the structure of the light projecting means 406.

The light projecting means is an auxiliary light source for performing exposure in photographing, and charges a strobe 411 which is also used as a signal light source for a normal distance measurement, and charges a light emitting capacitor of the strobe 411. The strobe 41
A strobe control circuit 412 for controlling the light emission of
An LED 41, which will be described later, based on a light emission request from the PU 105
LED driving circuit 417 for driving LED 6 and this LE
An LED 416 that is driven and controlled by a D drive circuit 417 to generate a signal light for distance measurement, and a light transmission pattern of the signal light for distance measurement by partially restricting a passing range of the signal light emitted from the LED 416. A pattern mask 415 formed using printing or the like, and a part of the pattern mask 415 are movably shielded from light, so that light shielding for switching the projection range of the pattern signal light for distance measurement is performed. The masks 414a and 414b and the CPU 10
5, the light-shielding masks 414a and 414b
And a light-shielding mask drive circuit 418 for controlling the position of the light-shielding mask 414 emitted from the pattern mask 415
a, and a light projecting lens 413 for projecting the distance-measuring pattern signal light, which has passed through the portion not shielded by the light emitting elements 414a and 414b, toward the subject.

Note that the LED 416 may emit visible light or may emit infrared light. LED that emits visible light
And an LED that emits infrared light may be provided, and may be switched as appropriate by setting the mode of the camera.

In the above description, the light-shielding masks 414a and 414b and the pattern mask 41 as shown in FIG.
5 was applied, but instead of FIG.
A configuration using an LED array as shown in FIG.

Next, with the distance measuring device having such a configuration,
For example, consider a case where distance measurement of a shooting scene as shown in FIG.

The light shielding masks 414a and 414b are not used to perform light shielding, and the pattern mask 415 is used as shown in FIG.
When the signal light for distance measurement of the light projection pattern 421 as shown in FIG. 0A is projected into the shooting screen and pre-emission integration is performed, reflection from a person as shown in FIG. Sensor data 422 obtained by integrating only light is obtained.

The light shielding masks 414a, 414
b is moved so that the pattern of the pattern mask 415 is projected only in the area where the reflected light from the person returns. This is the monitor area and calculation area 424 during the main light emission integration. By projecting signal light onto this area 424 and performing main light integration, sensor data 423 as shown in FIG. 20C is obtained. Based on this sensor data 423, calculation of distance measurement data is performed. Do.

If the amount of the reflected signal from the subject is small in the pre-projection integration, the main projection integration is performed using a strobe.

That is, when the strobe light 411 is used as a light source for performing the pre-light emission, for example, sensor data 425 as shown in FIG. 20D is obtained. The main subject may be detected from the sensor data 425, or may be switched by setting the camera mode or the like. Further, the monitor area and the calculation area at the time of the actual light emission integration are as indicated by reference numeral 426.

Next, a distance measuring sequence of the distance measuring apparatus will be described with reference to FIG.

When the operation is started, first, it is determined whether or not the photometric data has a luminance lower than a predetermined value (S40).
1). If the brightness is low here, step S described later
The process advances to step S <b> 402, while if it is not low luminance, the process advances to the next step S <b> 402. Here, instead of determining whether or not the brightness is low, the brightness may be determined based on the integration time in step S404 described later.

Subsequently, the monitor area for the steady light integration is set in the same manner as described in step S101 (S402).

Then, the sensor sensitivity for the steady light integration is set based on the photometric data, the pre-integration result, and the like (S40).
3).

With respect to the monitor area set in step S402, steady light integration is performed based on the sensor sensitivity set in step S403 (S404). The control of the integration at this time is performed by detecting whether the monitor data has reached a predetermined value or by determining whether a predetermined time has elapsed from the start of the integration.

The A / D conversion circuit 404 performs A / D conversion of the subject image signal obtained by the steady light integration in step S404, and reads the sensor data into the RAM in the CPU 105 (S405).

Thereafter, a predetermined calculation area for calculating the distance measurement data is set (S406). This calculation area is usually, for example, like the low-luminance part detection blocks 133, 134, and 135 shown in FIG.
Set multiple areas.

A predetermined correlation operation, interpolation operation, or the like is performed for each of the calculation regions set in step S406, and the shift amount (phase difference) of the pair of subject images formed on the pair of sensors by the pair of light receiving lenses. ) Is calculated, and the distance measurement data is calculated and calculated according to the known principle of triangulation (S407).

Based on the result of the calculation in step S407, it is determined whether or not distance measurement was impossible in all the areas set in step S406 (S408). If the distance cannot be measured, the process proceeds to step S409. If the distance cannot be measured, the process proceeds to step S409.
Proceed to 421.

Then, pre-projection integration is performed (S40).
9). At this time, the stationary light component is removed by the stationary light removing circuit 408, and only the reflected light component of the distance measurement signal light from the subject is integrated. This integration operation ends when a predetermined time has elapsed from the start of integration, regardless of the integration amount.

A / D conversion is performed on the subject image signal by the pre-projection integration in step S409 by the A / D conversion circuit 404, and is read into the RAM in the CPU 105 as sensor data (S410).

Thereafter, the main subject is determined (S41).
1). Here, in step S410, the CPU 105
From the sensor data read into the sensor data, the sensor number of the minimum value and the sensor data (minimum value among the minimum values) with the largest reflected signal light from the subject are detected.

It is determined whether or not the sensor data MIN with the largest reflected signal light from the subject detected as described above is larger than a predetermined value (S412).

If the sensor data MIN is larger than the predetermined value, a monitor area for main light emission integration (strobe light emission integration) is set (S422). The monitor area set at this time may be the whole area of the sensor or the area at the center of the shooting screen. Then, the main light emission integration (strobe light emission integration) is performed in the monitor area set in step S422.
Is performed (S423). The control of integration at this time is the same as in step S404 described above.

On the other hand, if the sensor data MIN is smaller than the predetermined value in step S412, it is next determined whether or not the sensor data MIN having the largest reflected signal light from the subject is smaller than the predetermined value. Yes (S4
13). If it is smaller here, step S41 described later
Proceed to 8.

If the sensor data MIN is larger than the predetermined value, the sensor data MIN having the largest reflected signal light from the subject detected in step S411 and the minimum data indicated by the sensor data number SDN equal to or smaller than the predetermined value are set. The projection area of the main projection integration (pattern projection integration) is set in the area including the area (S414).

Then, the main light emission integration (pattern light emission integration)
The monitor area is set (S415). At this time, as shown in the area 424 of FIG. 20C, the area is set to the area including the sensor in which the signal light reflected from the subject is the largest in the pre-projection integration in step S409.

Main light integration (pattern light integration) is performed in the light projection area set in step S414 and the monitor area set in step S415 (S416). The control of integration at this time is the same as in step S404.

A / D conversion is performed by the A / D conversion circuit 404 on the subject image signal obtained by the main light integration in step S 416 or step S 423, and the RA
It is read into M as sensor data (S417). The sensor data to be read at this time may be data of all the sensors, or may be only sensor data of the calculation area set in step S418 described later. However, when the flashlight integration is performed, all sensor data or sensor data at the center of the shooting screen is read.

Subsequently, a predetermined calculation area for calculating the distance measurement data is set (S418). The area set at this time may be the same as the monitor area 424 set in step S415, or may be set in step S4.
It may be set to a wider area including the light projection area set in 14 or a plurality of areas. However, when the strobe light integration is performed, a plurality of areas such as the low luminance portion detection blocks 133, 134, and 135 shown in FIG.

A predetermined correlation operation, interpolation operation, or the like is performed for each calculation region set in step S418, and the shift amount (phase difference) of the pair of subject images formed on the pair of sensors by the pair of light receiving lenses. ) Is calculated, and the distance measurement data is calculated according to the known principle of triangulation (S419).

Based on the result of the calculation in step S419, it is determined whether or not distance measurement was impossible in all the areas set in step S418 (S420).

If it is determined in step S420 or step S408 that the distance measurement is not impossible, the distance measurement data to be used for photographing is extracted from the distance measurement data obtained in step S407 and step S419, for example. A selection is made by a close selection or the like (S421).

On the other hand, if it is determined in step S420 that distance measurement cannot be performed, triangular distance measurement in which distance measurement is performed based on the amount of shift between a pair of normal subject images cannot be performed. Distance measurement (light amount AF) using the reflected light amount is performed (S424). Here, when calculating the distance measurement data, the data is corrected according to the light source that has projected the signal light so that the same distance measurement data is obtained if the object distance and the object reflectance are the same.

After performing step S421 or step S424, the process ends.

Next, the processing of the main subject determination sequence in step S411 will be described with reference to FIG.

When entering this processing, first, in step S410, the head address of the sensor data read into the RAM in the CPU 105 is set (S431).

Then, the minimum value M of the minimum value of the sensor data
IN (that is, sensor data having the largest reflected signal light from the subject) and a sensor data decrease flag F_DEC
, The sensor data number SDN of the minimum value, and the sensor data S immediately before the set sensor data address.
Dn-1 are initialized (S432). In this initialization, when the sensor data is 8-bit data, for example, MIN = FFH, F_DEC = 0, SDN
= 0, SDn-1 = 00H (the symbol H indicates a hexadecimal number).

Subsequently, the data of the set sensor data address is set in SDn (S433), and it is determined whether or not this sensor data SDn is smaller than the minimum value MIN (S434). The process proceeds to step S436 described below.

When the sensor data SDn has the minimum value MIN
If smaller, the sensor data SDn is set to the minimum value MIN (S435).

Then, it is determined whether or not the previous sensor data SDn-1 is smaller than the sensor data SDn (S43).
6) If large, sensor data decrease flag F_D
After setting 1 in EC (S444), the process proceeds to step S441 described later.

On the other hand, if the sensor data SDn-1 is smaller than the sensor data SDn, it is determined whether or not the sensor data decrease flag F_DEC = 1 (S437).
If it is, the process proceeds to step S440 described below.

On the other hand, the sensor data decrease flag F
If _DEC is 1, the previous sensor data S
It is determined whether Dn-1 is smaller than a predetermined value (S43).
8) If it is larger, the process proceeds to step S440 described later.

If the sensor data SDn-1 is smaller than the predetermined value, the sensor data number SD
N is stored (S439).

Thereafter, the sensor data decrease flag F_DE
C is set to 0 (S440), the sensor data number SDN is counted up (S441), and the next sensor data address is set (S442).

Then, it is determined whether or not the processing has been completed for all sensor data (S443). If not completed, the process returns to step S433 to repeat the processing, while it is determined that the processing has been completed. If it does, return.

According to the fourth embodiment, substantially the same effects as those of the above-described first to third embodiments can be obtained, and a main subject is detected by pre-projection integration.
Since the main integration is performed by projecting the signal light only to the main subject, unnecessary components other than the main subject are eliminated, and high-accuracy distance measurement can be performed.

FIG. 23 shows a fifth embodiment of the present invention and is a flowchart showing a distance measuring sequence of the distance measuring apparatus. In the fifth embodiment, a description of the same parts as those in the above-described first to fourth embodiments will be omitted, and only different points will be mainly described.

The structure of the distance measuring apparatus and the structure of the light projecting means of the fifth embodiment are the same as those of the fourth embodiment shown in FIG.
(A), FIG. 18 (B), FIG. 19, etc.

In the distance measuring apparatus according to the fourth embodiment,
If the distance cannot be measured or the brightness is low due to the steady light integration, the main subject is determined by the pre-projection integration, and the distance measurement signal light is projected to the main subject detected by the main projection integration to measure the distance. I was going.

On the other hand, in the distance measuring apparatus of the fifth embodiment, first, a main subject is determined by pre-projection integration, and the monitor area and the distance measurement data are set in the area where the detected main subject exists. A calculation area is set, and distance measurement is performed by steady light integration. Then, when the distance cannot be measured by the distance measurement by the stationary light integration, the distance measurement by the main light integration is performed.

In the pre-light integration, when the reflected signal light from the subject is small and the photographic scene has low brightness, the main light integration is performed using the strobe 411 as shown in FIG.

Now, the distance measuring sequence of the distance measuring means will be described with reference to FIG.

When this process is started, first, pre-light integration is performed (S501). At this time, the stationary light component is removed by the stationary light removing circuit 408, and only the reflected light component of the distance measurement signal light from the subject is integrated. In addition, the integration ends when a predetermined time has elapsed from the start, regardless of the amount of integration.

The subject image signal obtained by the pre-projection integration in step S501 is converted into an A / D signal by the A / D conversion circuit 404.
The data is D-converted and read into the RAM in the CPU 105 as sensor data (S502).

Then, the main subject is determined (S50).
3). Here, in step S502, the CPU 105
, The sensor value of the minimum value and the sensor data (minimum value among the minimum values) MIN with the largest signal light reflected from the subject are detected.

Thereafter, it is determined whether or not the sensor data MIN having the largest reflected signal light from the subject is larger than a predetermined value (S504). Here, when it is determined to be large, the process proceeds to step S521 described later, and when it is determined to be small, the process proceeds to the subsequent step S505.

Here, it is determined whether or not the sensor data MIN with the largest reflected signal light from the subject is smaller than a predetermined value (S505). Here, when it is determined to be smaller, the process proceeds to step S510 described later, and when it is determined to be larger, the process proceeds to the subsequent step S506.

Further, a monitor area for steady light integration is set (S506). The monitor area is a sensor range in which the average value of the sensor data and the integration amount of the sensor with the fastest integration speed are output to the integration control circuit 403 as monitor data in the area for controlling the integration. More specifically, as shown in the monitor area 424 shown in FIG. 20C, the area is set to an area including the sensor having the largest signal light reflected from the subject in the pre-projection integration in step S503. However, if the reflected signal light from the subject is small,
The sensor is set so as to cover the entire area or a relatively wide area.

Thereafter, the sensor sensitivity for the steady light integration is set based on the photometric data, the pre-integration result, and the like (S50).
7).

For the monitor area set in step S 506, steady light integration is performed based on the sensor sensitivity set in step S 507 (S 508). The control of the integration at this time is performed by detecting whether the monitor data has reached a predetermined value or by determining whether a predetermined time has elapsed from the start of the integration.

The subject image signal obtained by the steady light integration in step S508 is A / D converted by the A / D conversion circuit 404, and is read into the RAM in the CPU 105 as sensor data (S509). The sensor data to be read at this time may be the data of all the sensors, or may be only the sensor data of the calculation area set in the next step S510.

Then, a predetermined calculation area for calculating the distance measurement data is set (S510). The area set here is the monitor area 4 set in step S506.
24, or a plurality of settings may be made so as to include the monitor area 424 or the monitor area 424. However, when the reflected signal light from the subject is small, for example, the low luminance portion detection block 133 shown in FIG.
A plurality of areas are set, such as 134 and 135.

A predetermined correlation operation, interpolation operation, or the like is performed for each operation region set in step S510, and a shift amount (phase difference) of a pair of subject images formed on a pair of sensors by a pair of light receiving lenses. ) Is calculated, and the distance measurement data is calculated according to the known principle of triangulation (S511).

On the basis of the result of the calculation in step S511, it is determined whether or not distance measurement was impossible in all the areas set in step S510 (S512). If the distance cannot be measured, the process proceeds to step S513. If the distance cannot be measured, the process proceeds to step S513 described later.
Proceed to 520.

The sensor data MI having the largest reflected signal light from the object detected in step S503
A projection area of the main light integration (pattern light integration) is set in an area including the minimum data indicated by N and a sensor data number SDN equal to or less than a predetermined value (S513).

Next, a monitor area for main light emission integration (pattern light integration) is set (S514). Here, as in the region 424 shown in FIG.
In the pre-projection integration of 503, the area is set to the area including the sensor where the reflected signal light from the subject is the largest.

Further, main light integration (pattern light integration) is performed in the light projection area set in step S513 and the monitor area set in step S514 (S51).
5). The control of the integration at this time is performed in step S508 described above.
Is the same as

On the other hand, if the sensor data MIN is smaller than the predetermined value in step S504, it is determined whether or not the photometric data has a lower brightness than the predetermined value (S521). If so, the process proceeds to step S506. Note that the luminance determination may be performed based on the integration time or the like in step S508 as described above.

If it is determined in step S521 that the photometry data has a luminance lower than the predetermined value,
A monitor area for the main light emission integration (strobe light emission integration) is set (S522). The monitor area set at this time is
The whole area of the sensor or the area in the center of the photographing screen may be used.

Then, main light emission integration (flash light emission integration) is performed in the monitor area set in step S522 (S523). The control of integration at this time is the same as in step S508 described above.

Next, the subject image signal obtained by the main light integration in step S515 or step S523 is subjected to A / D conversion.
A / D conversion is performed by the conversion circuit 404, and the R
The data is read into the AM as sensor data (S516). At this time, the sensor data to be read may be data of all sensors, or may be only sensor data of the calculation area set in the next step S517. However, when the flashlight integration is performed, all sensor data or sensor data at the center of the shooting screen is read.

Further, a predetermined calculation area for calculating the distance measurement data is set (S517). The area set at this time may be the same as the monitor area 424 set in step S514, or may be set in step S5.
It may be set to a wider area or a plurality of areas including the light projection area set in step S13. However, when the strobe light integration is performed, it is set in a plurality of areas such as the low luminance portion detection blocks 133, 134, and 135 shown in FIG.

A predetermined correlation operation, interpolation operation, or the like is performed for each operation region set in step S517, and the shift amount (phase difference) of the pair of subject images formed on the pair of sensors by the pair of light receiving lenses. ) Is calculated, and distance measurement data is calculated by a known triangulation principle (S518).

Based on the result of the calculation in step S518, it is determined whether or not distance measurement was impossible in all the areas set in step S517 (S519). If the distance cannot be measured here, step S524 described later is performed.
To the next step S if the distance measurement is not possible
Proceed to 520.

If it is determined in step S519 that distance measurement is not possible, distance measurement data to be used for photographing is selected from the distance measurement data obtained in steps S511 and S518 by selecting the closest distance or the like (step S519). S52
0).

If it is determined in step S519 that the distance cannot be measured, the signal light projected on the object cannot be obtained because triangular distance measurement in which distance measurement is performed based on the amount of shift between a pair of normal object images cannot be performed. Distance measurement using the reflected light amount is performed (S524). When calculating the distance measurement data, the data is corrected according to the light source onto which the signal light is projected so that the same distance measurement data is obtained if the object distance and the object reflectance are the same.

When the above step S520 or step S524 is completed, this processing is completed.

According to the fifth embodiment, substantially the same effects as those of the above-described first to fourth embodiments can be obtained, and a main subject is detected by pre-projection integration.
A high-speed and high-precision distance measurement is performed without performing unnecessary calculations because the monitor area and the calculation area of the distance measurement data are set in the area where the main subject exists and distance measurement is performed by steady light integration. It can be performed.

FIGS. 24 to 27 show a sixth embodiment of the present invention. FIG. 24 is a block diagram showing the structure of the light projecting means of the distance measuring device, and FIG. 25 is equipped with the distance measuring device. FIG. 26 is a plan view showing a camera, FIG. 26 is a diagram showing an example of switching a light source of a signal light for distance measurement and an example of switching a projection range, and FIG. 27 is a flowchart showing a distance measuring sequence of the distance measuring device.

In the sixth embodiment, the first
The description of the same parts as those of the fifth embodiment will be omitted, and only different points will be mainly described.

In the sixth embodiment, FIGS. 1 (A), 1 (B) and 1
In the distance measuring device as shown in FIG. 8 (A) or FIG. 18 (B), the photographer decides whether or not to forcibly project the signal light for distance measurement, and switches the projection range and the projection light source. It can be set manually.

The light projecting means of this distance measuring device is shown in FIG.
This will be described with reference to FIG.

The light projecting means is a strobe light 601 which is an auxiliary light source for performing exposure in photographing and which is normally used also as a signal light source for distance measurement of a long distance subject.
A flash control circuit 60 for charging the light emitting capacitor of the strobe 601 and controlling the light emission of the strobe 601
2 and LEDs 604 a, 604 b, 604 c, 604 d, and 6 based on a light emission request from the CPU 105.
LED drive circuit 605 for driving the light emitting device 04e, and LEDs 604a, 604b, and 604 that are driven and controlled by the LED drive circuit 605 to generate signal light for distance measurement.
c, 604d, 604e and these LEDs 604a,
A light projecting lens 603 for projecting the signal light for distance measurement emitted from 604b, 604c, 604d, and 604e toward a subject, and a self LED driving circuit 607 for driving a self LED 606 described later based on a command from the CPU 105. And a self LED which is driven by the self LED driving circuit 607 and emits light, which is a display light source of a self timer and is also used as a signal light source for distance measurement.
606, forced light emission setting means 608 for the photographer to set the forced light emission mode, and the photographer
Light source switching means 609 for selecting a signal light source for distance measurement including the above-mentioned self LED 606 and the like, and the photographer can select the LED 604a, 604b, 604c, 604d,
A projection range switching unit 610 for selecting a projection range of signal light for distance measurement such as 604e;
Is configured.

The LEDs 604a, 604b, 6
04c, 604d, and 604e may emit visible light or may emit infrared light. Further, both a LED that emits visible light and an LED that emits infrared light may be provided so that the photographer can select the LED.

In addition, the LED arrays 604a, 604
Instead of b, 604c, 604d, and 604e, light shielding masks 122a and 122b as shown in FIG.
And the pattern mask 123 may be used to switch the light projection range.

Next, FIG. 25 shows a camera equipped with a distance measuring device as described above.

In this camera, various kinds of information relating to the camera, such as the number of frames to be shot, date, setting mode, signal light source for setting distance measurement, and setting distance measurement Display means 612 such as a liquid crystal plate for displaying the signal light projection range for use, and the compulsory light emission mode for forcibly projecting the signal light for distance measurement regardless of shooting conditions during distance measurement. A forced light emission setting button 613 corresponding to the light emission setting means 608; a light emission light source switching button 614 corresponding to the light emission light source switching means 609 for selecting a signal light source for distance measurement; A projection range switching button 615 corresponding to the projection range switching means 610 for selecting the projection range of the signal light, and a release button 616 for photographing
And, it is arranged and configured.

The above buttons 613 and 613 for setting and switching are set.
It is needless to say that the buttons 614, 615 and the like do not necessarily have to be configured as buttons, but may be other input means such as a dial.

In such a configuration, when the photographer sets the forced light emission mode using the forced light emission setting means 608 (forced light emission setting button 613), the signal light for distance measurement is projected regardless of the photographing conditions. In addition to performing distance measurement, the display means 612 displays that the forced light emission mode has been set.

Also, the photographer can switch the light emitting light source switching means 6
When the light source 09 (light projection light source switching button 614) is pressed, the signal light source used for distance measurement is switched cyclically as shown in FIG.
, The set light source is displayed.

That is, when the projection light source switching means 609 is pressed, the display means 612 displays a display A for automatically switching the signal light source for distance measurement in accordance with the photographing conditions.
UTO and LED 604a as a signal light source for distance measurement,
Display LEDs when only 604b, 604c, 604d and 604e are used, strobes when only the strobe 601 is used as a signal light source for distance measurement, and only self LEDs 606 as a signal light source for distance measurement Is displayed in order when the self-display is used, and when the light projection light source switching unit 609 is further pressed while the self-display is displayed, the display returns to the AUTO display.

Further, when the photographer presses the light emitting range switching means 610 (light emitting range switching button 615), each time the photographer presses the light emitting range switching means 610, the light source shown in FIG.
ED 604a, 604b, 604c, 604d, 604
As shown in FIG. 26B, e is switched cyclically, and the set projection range is displayed on the display means 612 or a finder (not shown).

That is, when the light projection range switching means 610 is pressed, the display means (or the display screen of the finder) 62 is displayed.
1, a projection range display 622a when the LED 604a is selected, a projection range display 622b when the LED 604b is selected, a projection range display 622c when the LED 604c is selected, and the LED 604d are selected. Light emitting range display 622d when the LED 604e is selected, and light emitting range display 622e when the LED 604e is selected.
a, 604b, 604c, 604d, and 604e are all displayed, and ALL, which is a display when projecting the signal light for distance measurement, is sequentially displayed. In the state where ALL is displayed, the light projection range switching is further performed. When the means 610 is pressed, the display returns to the state in which the light projection range display 622a is displayed.

Note that all the LEDs 604a, 604b,
To make 604c, 604d, and 604e emit light,
Instead of displaying characters such as ALL, all of the projection range displays 622a, 622b, 622c, 622d, and 622e may be displayed.

Next, a distance measuring sequence of the distance measuring apparatus will be described with reference to FIG.

When this process is started, first, it is determined whether or not the forced light emission mode is set (S60).
1). If the mode is the forced light emission mode, the process proceeds to step S610 described below. If the mode is not the forced light emission mode, the process proceeds to step S602.

Next, it is determined whether or not the photometric data has a luminance lower than a predetermined value (S602). Here, if the brightness is low, the process proceeds to step S610 described below, while if the brightness is not low, the process proceeds to the subsequent step S603. Note that the luminance determination may be performed based on the integration time in step S605 described later.

Then, a monitor area for steady light integration is set (S603). The monitor area is a sensor range in which the integration control circuit 103 or 403 outputs the average value of the sensor data in the area or the integration amount of the sensor with the fastest integration speed as monitor data in order to perform integration control. This monitor area is usually set to be the entire sensor area or a relatively large area.

Subsequently, the sensor sensitivity for steady light integration is set based on the photometric data, the pre-integration result, and the like (S60).
4).

Thereafter, for the monitor area set in step S603, steady light integration is performed using the sensor sensitivity set in step S604 (S60).
5). The control of the integration at this time is performed by detecting whether the monitor data has reached a predetermined value or by determining whether a predetermined time has elapsed from the start of the integration.

The subject image signal obtained by the steady light integration in step S605 is converted into an A / D signal by the A / D conversion circuit 104.
The data is converted and read into the RAM in the CPU 105 as sensor data (S606).

Then, a predetermined calculation area for calculating the distance measurement data is set (S607). Normally, a plurality of regions are set in this calculation region, for example, similarly to the low luminance portion detection blocks 133, 134, and 135 as shown in FIG.

A predetermined correlation operation, interpolation operation, or the like is performed for each operation area set in step S607, and a shift amount (phase difference) of a pair of subject images formed on a pair of sensors by a pair of light receiving lenses. ) Is calculated, and the distance measurement data is calculated according to the known principle of triangulation (S608).

Based on the result of the calculation in step S608, it is determined whether or not distance measurement has been impossible in all the areas set in step S607 (S609). If the distance cannot be measured, the process proceeds to step S610. If the distance cannot be measured, step S610 will be described later.
Proceed to 623.

Next, the light projection light source switching means 609 determines whether or not the self LED 606 is set as a signal light source for distance measurement (S610). If it is set here, the process proceeds to step S621 described later, while if it is not set, the process proceeds to the subsequent step S611.

Further, the light projection light source switching means 609 determines whether or not the strobe 601 is set as the signal light source for distance measurement (S611). If it is set here, the process proceeds to step S622 described later, while if it is not set, the process proceeds to the subsequent step S612.

The LEDs 604a, 604b,
Of the 604c, 604d and 604e, the one set by the projection range switching means 610 is set as the signal light source for distance measurement, and the monitor area is set in an area corresponding to the set projection range. (S612).

Furthermore, the LEDs 604a, 604b,
Steps S6 out of 604c, 604d, and 604e
Signal light is projected from the LED set in step S12, and integration is performed in the monitor area set in step S612 (S
613). The control of the integration at this time is performed in the step S6.
Same as 05.

In the integration in step S613,
It is determined whether the amount of signal light reflected from the subject is smaller than a predetermined amount based on the integration speed, integration time, and the like (S
614). Here, when it is determined to be smaller, the process proceeds to the subsequent step S615, and when it is determined to be larger, the process proceeds to step S616 described later.

The light emitting light source switching means 609 controls the LEDs 604a and 604 as signal light sources for distance measurement.
It is determined whether 04b, 604c, 604d, and 604e are set (S615). Here, if the LED is set, the process proceeds to the subsequent step S616. If the LED is not set, the process proceeds to step S62 described later.
Proceed to 2.

The subject image signal obtained by each integration is A / D converted by the A / D conversion circuit 104, and is read into the RAM in the CPU 105 as sensor data (S616).

Next, a predetermined calculation area for calculating the distance measurement data is set (S617). This calculation area is usually set to the LEDs 604a, 604b, 604c, and 604.
Unless one of d and 604e is set, a plurality of areas are set, for example, as in the low luminance portion detection blocks 133, 134 and 135 shown in FIG. On the other hand, the LEDs 604a, 604b, 60
When any one of 4c, 604d, and 604e is set, the area is set to an area corresponding to the set LED.

Then, a predetermined correlation operation, interpolation operation and the like are performed for each operation region set in step S617, and
A shift amount (phase difference) between a pair of subject images formed on a pair of sensors by a pair of light receiving lenses is obtained, and distance measurement data is calculated and calculated according to a known principle of triangulation (S61).
8).

On the basis of the result of the calculation in step S618, it is determined whether or not distance measurement was impossible in all the areas set in step S617 (S619). If the distance cannot be measured, the process proceeds to step S620. If the distance cannot be measured, step S620 will be described later.
Proceed to 623.

If it is determined in step S619 that distance measurement is impossible, triangular distance measurement in which distance measurement is performed based on the amount of shift between a pair of normal subject images cannot be performed. Distance measurement using light amount is performed. When calculating the distance measurement data, the data is corrected according to the light source that has projected the signal light so that the same distance measurement data is obtained if the subject distance and the subject reflectance are the same (S62).
0).

On the other hand, if the self LED 606 has been set in step S610,
Signal light is projected from the ED 606, the monitor area is set to the entire sensor area or a relatively wide area, and integration is performed (S6).
21) Then, the process proceeds to step S616.

If the strobe 601 has been set in step S611, or if the LEDs 604a, 604b, and 604 have been set in step S615.
If c, 604d and 604e are not set,
Signal light is projected from the strobe 601 to perform integration by setting the monitor area to the whole area of the sensor or a relatively wide area (S622), and then go to the step S616.

If it is determined in step S609 or step S619 that distance measurement is possible, step S608 and step S618 are performed.
The distance measurement data to be used for photographing is selected from the distance measurement data obtained in step (S623).

When the above step S620 or step S623 has been completed, this processing ends.

According to the sixth embodiment, substantially the same effects as those of the above-described first to fifth embodiments can be obtained, and the user can manually forcibly project the signal light for distance measurement. To perform high-precision distance measurement by setting the photographer in various shooting environments because it is possible to switch whether or not to perform the measurement, and to switch the projection light source and range of the signal light for distance measurement. Can be.

It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various modifications and applications are possible without departing from the gist of the invention.

[Supplementary notes] According to the above-described embodiment of the present invention as described in detail above, the following configuration can be obtained.

(1) A pair of light receiving lenses for forming a subject image and a pair of photoelectric conversion means for converting the pair of subject images formed by these light receiving lenses into electric signals according to the light intensity, respectively. Integration control means for performing integral control of the pair of photoelectric conversion means, calculation means for calculating data corresponding to a subject distance based on subject image data output from the pair of photoelectric conversion means, and measurement for the subject. A distance measuring device comprising: at least one light projecting means for projecting a signal light for distance, wherein the light projecting condition is switched based on a subject condition or a state of a camera.

(2) The distance measuring apparatus according to (1), wherein the photoelectric conversion means is a line sensor.

(3) The distance measuring apparatus according to (1), wherein the photoelectric conversion means is an area sensor.

(4) The subject condition or the camera state includes at least one of a luminance distribution in the photographing screen, a posture and setting of the camera, a reflected light distribution of the pre-projection, and a contrast of the subject. The distance measuring apparatus according to (1), further comprising:

(5) The light projecting condition is that at least one of the shape of the light projecting pattern, the light projecting range, and the wavelength of the projecting light.
The distance measuring apparatus according to (1), further comprising:

(6) It further comprises a stationary light removing means for removing stationary light constantly entering the photoelectric conversion means,
The distance measuring apparatus according to (1), further comprising a function of integrating only the reflected light from the subject of the signal light.

(7) The light emitting means has a plurality of light emitting elements, and the shape of the light emitting pattern or the light emitting range is switched by switching the light emitting elements of the light emitting means. The distance measuring apparatus according to supplementary note (5), characterized in that:

(8) The light projecting means is provided with a mask pattern for defining a pass range of the signal light to be projected, and the shape of the light projecting pattern or the switching of the light projecting range is changed by the mask pattern of the light projecting means. The distance measurement device according to (5), wherein the distance measurement is carried out by switching.

(9) A plurality of the light projecting means are provided, and the shape of the light projecting pattern, the light projecting range, or the wavelength of the projected light is switched by switching the light projecting means. The distance measuring apparatus according to supplementary note (5), characterized in that:

(10) A light measuring means for measuring the brightness of the object is further provided, and the shape of the light emitting pattern or the light emitting range can be switched by measuring the light measuring data of the light measuring means or the object outputted from the photoelectric conversion means. The distance measurement according to (5), wherein a low-luminance area in the photographing screen is detected based on the image data, and the signal light is projected onto the detected low-luminance area. apparatus.

(11) The state of the camera includes the attitude of the camera, and the shape of the light emitting pattern or the switching of the light emitting range is determined according to whether the attitude of the camera is vertical or horizontal. (5) The distance measuring apparatus according to (5), wherein the distance measurement is performed.

(12) The light emitting means according to (1), wherein, when the camera is set to the normal mode, the light emitting means projects the signal light over the entire range of the distance measuring range. Distance measuring device.

(13) The light emitting means according to (1), wherein when the camera is set to the spot mode, the light projecting means projects the signal light only at the center of the photographing screen. Distance measuring device.

(14) The plurality of light projecting means include infrared light projecting means for projecting infrared light, and the camera is set to at least one of a portrait mode, a night view mode, and a strobe off mode. The distance measuring apparatus according to (6), wherein when set, infrared light is projected by the infrared light projecting means.

(15) The plurality of light projecting means include an LED which also has a display function of a self-timer, and when the camera is set to the macro mode,
The distance measuring device according to (6), wherein signal light for distance measurement is projected by the display LED of the self-timer.

(16) The light emitting means according to (1), wherein the light emitting means is configured not to emit the signal light when the camera is set to the landscape mode. Distance measuring device.

(17) The distance measuring apparatus according to (4), wherein the light projecting means projects the signal light to an area where the amount of reflected light in the distribution of reflected light by pre-lighting is large.

(18) The plurality of light projecting means include a strobe as a light projecting means and a light projecting means other than the strobe, and when the signal light is projected by the light projecting means other than the strobe. In addition, when the amount of the reflected signal from the subject is small, the distance is measured by projecting the signal light with a strobe to measure the distance.

(19) The distance measuring apparatus according to (1), further comprising a light emitting range switching means for allowing a photographer to manually set a light emitting range of the light emitting means.

(20) The distance measuring apparatus according to (1), further comprising a light emitting light source switching means for allowing a photographer to manually set a light emitting range of the light emitting means.

(21) A forced light emission setting means for allowing a photographer to set a forced light emission mode in which a signal light for distance measurement is projected from the light emitting means to a subject regardless of a shooting condition to perform distance measurement. (1) The distance measuring apparatus according to (1), further comprising:

[0309]

As described above, according to the distance measuring apparatus of the present invention, it is possible to perform high-precision distance measurement according to the subject condition or the state of the camera.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a distance measuring device using a line sensor (A) and an area sensor (B) as light receiving elements in a first embodiment of the present invention.

FIG. 2 shows (A) a plurality of L in the first embodiment.
FIG. 3 is a block diagram showing the configurations of a light projecting unit using an ED and (B) a light projecting unit using a movable light shielding mask for switching a light projecting range.

FIG. 3 is a view showing a view of a finder visual field when a main subject has low luminance with respect to a background in the first embodiment, and FIG. FIG. 3 is a diagram illustrating image data, and FIG. 3C is a diagram illustrating subject image data when a signal light is projected onto a central portion of a main subject and integrated.

FIG. 4 is a diagram showing a modified example of the light projection pattern of the signal light by the plurality of LEDs in the first embodiment.

5A and 5B are diagrams showing an example of switching of a light projecting range of the light projecting means using the movable light shielding mask of the first embodiment, and FIG.
The figure which shows arrangement | positioning of the light-shielding mask when projecting signal light to the whole area | region of an imaging screen, (B) the center part of an imaging screen, (C) the left part of an imaging screen, and (D) the right part of an imaging screen respectively .

FIG. 6 is a view showing a light projection range and a pattern example on a photographing screen by a light projection unit using the movable light shielding mask of the first embodiment.

FIG. 7 is a flowchart showing a distance measuring sequence of the distance measuring apparatus according to the first embodiment.

FIG. 8 is a flowchart showing a low-brightness / low-contrast determination process according to the first embodiment.

FIG. 9 is a block diagram showing a configuration of a light projecting unit of a distance measuring apparatus according to a second embodiment of the present invention.

FIG. 10 is a diagram showing an example of a light projection range and a pattern example in a shooting screen by each ranging signal light source in the second embodiment.

FIG. 11 is a flowchart showing a distance measuring sequence of the distance measuring apparatus according to the second embodiment.

FIG. 12 is a block diagram illustrating a configuration of a light projecting unit of a distance measuring apparatus according to a third embodiment of the present invention.

FIG. 13 is a perspective view showing an example of a distance measuring device configured using a line sensor in the third embodiment.

FIG. 14 is a view showing an example of a pattern printed on a pattern mask in the third embodiment.

FIG. 15 is a diagram showing a projection pattern of signal light for distance measurement by a pattern mask into a shooting screen in the third embodiment.

FIG. 16 is a block diagram showing a configuration example of a camera posture detection unit according to the third embodiment.

FIG. 17 is a flowchart showing a distance measuring sequence of the distance measuring apparatus according to the third embodiment.

FIG. 18 is a block diagram showing a configuration of a distance measuring apparatus using a line sensor (A) and an area sensor (B) as light receiving elements in a fourth embodiment of the present invention.

FIG. 19 is a diagram showing a configuration of a light projecting unit of the distance measuring apparatus according to the fourth embodiment.

FIG. 20 is a diagram showing an example of a shooting scene and subject image data relating to the shooting scene in the fourth embodiment.

FIG. 21 is a flowchart showing a distance measuring sequence of the distance measuring apparatus according to the fourth embodiment.

FIG. 22 is a flowchart showing main subject determination processing according to the fourth embodiment.

FIG. 23 is a flowchart showing a distance measuring sequence of the distance measuring apparatus according to the fifth embodiment of the present invention.

FIG. 24 is a block diagram showing a configuration of a light projecting unit of a distance measuring apparatus according to a sixth embodiment of the present invention.

FIG. 25 is a plan view showing a camera equipped with the distance measuring apparatus according to the sixth embodiment.

FIG. 26 is a diagram showing an example of switching the light source of the signal light for distance measurement and an example of switching the projection range in the sixth embodiment.

FIG. 27 is a flowchart showing a distance measuring sequence of the distance measuring apparatus according to the sixth embodiment.

[Explanation of symbols]

101a, 101b: light receiving lenses 102a, 102b: line sensors 107a, 107b: area sensors 103: integration control circuit (integration control means) 105: CPU (calculation means) 106: light projecting means 112a, 112b, 112c, 112d, 112e ...
LED 123 ... pattern mask 122a, 122b ... light-shielding mask 204a, 204b, 204c, 204d, 204e ...
Infrared LED 206 self LED 303 LED 302a, 302b pattern mask 306 camera attitude detecting means 312a, 312b, 312c, 312d line sensors 401a, 401b light receiving lenses 402a, 402b line sensor 403 integration control circuit ( Integration control means) 406 light emitting means 407a, 407b area sensor 408 stationary light removing circuit 411 strobe 414a, 414b light shielding mask 415 pattern mask 601 strobe 604a, 604b, 604c, 604d, 604e
LED 606 self LED 608 forced light setting means 609 light source switching means 610 light range switching means

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) G03B 7/28 G03B 3/00 A F term (reference) 2F065 AA06 DD03 FF01 FF05 FF09 FF12 FF21 GG07 GG08 HH02 HH06 JJ02 JJ03 JJ05 JJ25 JJ26 LL25 LL28 QQ03 QQ14 QQ41 2F112 AC06 BA06 BA20 CA02 DA13 EA07 EA09 EA20 FA03 FA07 FA21 FA29 FA35 FA41 FA45 2H002 DB02 DB24 FB29 GA54 HA01 2H011 AA01 BA05 BB04 DA01 DA08 2H051 BB07 CC03 CC07 DA07

Claims (3)

[Claims] A pair of light receiving lenses for forming a subject image, a pair of line sensors for converting the pair of subject images formed by the light receiving lenses into electric signals in accordance with light intensity, respectively; Integral control means for performing integral control of the pair of line sensors; computing means for computing data corresponding to a subject distance based on subject image data output from the pair of line sensors; and a distance measurement signal for the subject. A distance measuring device, comprising: at least one light projecting means for projecting light, wherein the light projecting condition is switched based on a subject condition or a state of a camera. 2. A pair of light receiving lenses for forming respective subject images, a pair of area sensors for converting the pair of subject images formed by these light receiving lenses into electric signals in accordance with light intensity, respectively; Integration control means for performing integral control of the pair of area sensors; computing means for calculating data corresponding to a subject distance based on subject image data output from the pair of area sensors; and a distance measurement signal for the subject. And at least one light projecting means for projecting light, wherein the light projecting means, when projecting the signal light for distance measurement, luminance distribution in a photographing screen, posture and setting of a camera, pre-light projecting The light projection is performed by switching at least one of the shape of the light projection pattern, the light projection range, and the wavelength of the projection light in accordance with at least one of the reflected light distribution and the contrast of the subject. Distance measuring device. 3. The apparatus according to claim 1, further comprising a stationary light removing means for removing stationary light constantly entering the line sensor or the area sensor, and having a function of integrating only the reflected light from the subject of the signal light. The distance measuring apparatus according to claim 1 or 2, wherein