JPH06175187A - Camera and light projecting means - Google Patents

Abstract

PURPOSE:To accurately decide the kind of a light source for an object just by providing one colorimetry sensor by deciding the kind of the light source in the case light is projected by a light projecting means and in the case the light is not projected based on output from a colorimetric means. CONSTITUTION:One photometry sensor 4, a stroboscope 24, and a stroboscopic circuit 25 are provided. While the stroboscope 24 emits the light, colorimetry is performed. While a lens position signal is obtained from an encoder 22 by a lens driving actuator 2, a photographing lens 1 is driven in accordance with range-finding information, a shutter 3 is opened, the stroboscope 24 emits the light, and the shutter 3 is closed to perform colorimetric arithmetic operation. Furthermore, as a recording sequence, the photographic frame of film is fed by one, and encoded information on the light source is transmitted from a buffer 23 to a readout and write head H and recorded in a track T on the film F. Based on the photometry information from a photometric block 4, colorimetry detection is set to daylight when the object is very bright, and at such a time, the colorimetric arithmetic operation is performed while the daylight is still set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera having a light source detection device for detecting the kind of light source in a general camera, regardless of whether it is a video (still, movie) or a silver salt, to improve a photographing result. is there.

[0002]

2. Description of the Related Art A conventional photographing light source detection device for a camera is shown in Japanese Patent Application No. 4-27551.

8 to 10 are views showing the configuration of a conventional light source detection device. In the figure, 1 is a taking lens, 2 is a lens actuator that drives the taking lens 1, and a lens encoder that generates a lens position signal, 3 is a lens shutter, 4 is a photometric sensor for AE, and 5 is a light receiving angle of the photometric sensor. Determining lens, 6 is distance measuring block and finder block, 7 is perforation P of film F
1, a photo-reflector for detecting the P2 and feeding the film at a fixed length, 8 a film feeding motor arranged in a spool, 9 a gear train for decelerating and switching between winding and rewinding, 10 a winding A return fork, FC is a film cartridge, F is a film having a magnetic layer coated on the base side, P1 and P2 are perforations corresponding to the photographing screen X, H is a magnetic head for writing information on a track T on the film F, 11 Is a pressure-bonding pad that presses the film against the head, and has a recess in the center to enhance the adhesion between the film and the head gap. 12 is a pad retracting mechanism that presses the pad 11 against the head with a predetermined pressure only during film feeding, S1 to S3 are colorimetric sensors, and 13 to
Reference numeral 15 is a white diffuser plate corresponding to each colorimetric sensor, S1 has a sensitivity to the rear of the camera, S2 has an upper sensitivity, and S3 has a sensitivity to the front. 1
Reference numeral 6 is a release button, 17 is SW1 for starting photometry and distance measurement, and 18 is SW2 for starting a sequence of opening a shutter and film feeding. M1 to M3 are colorimetric circuits to which the outputs of the colorimetric sensors S1 to S3 are input, and the luminance signals V _B1 , V _B2 , V _B3 , and the color signals V _C1 , respectively.
It outputs V _C2 and V _C3 .

The operation sequence of the camera will be described below. When the film cartridge C is loaded, the camera first winds up all of the film F. At this time, the camera reads information such as film sensitivity, the number of shots, and film type recorded on the magnetic layer by the magnetic head H, amplifies by the head amplifier 19, A / D-converts, and then transfers to the buffer 20. . When the predetermined information is transferred, the decoder 2
1 decodes each information and transfers it to the CPU. The CPU counts the number of frames by the output of the perforation 7 for detecting one frame, and stops the winding when the previously read number of shots is reached. When SW1 is turned on, distance measurement, photometry, and color measurement are performed, each information is processed by the CPU, and exposure standby is set. The colorimetric signal processed by the CPU is converted into light source information, coded by the encoder 2, and stored in the buffer 23. When SW2 is turned on here,
The lens drive actuator 2 outputs the lens position signal from the encoder to the CPU, drives the photographing lens 1 until the stop command from the CPU, stops the positioning, and performs the focus operation. After that, after the shutter 3 is opened and closed for a time determined by the output of the light receiving element 4, one frame rewinding is performed until the constant length detection is performed. At this time, the buffer 23
The coded light source information is sent to the head H via the head amplifier 19 and written on the track T on the film F. After that, when the photographing of a predetermined number of frames is completed, the rewinding is continued until all the films are in the cartridge C, and then the film is stopped.

The above is the sequence in use. During this time, the pressure bonding pad 11 is pressed against the head H only while the film F is moving to ensure the reading and writing of magnetic information.

An example of the colorimetric sensor will be described with reference to FIGS. 10 (a) and 10 (b). Figure 10 (b)
FIG. 6 is a diagram showing a correspondence between a cross section of an element and a terminal in a circuit diagram in a sensor of a conventional example. In the figure, two PN junctions are laminated on a silicon substrate, and the distance from the surface of the silicon substrate is different, so the first junction J1
Has a shorter wavelength, and the second junction J2 has a sensitivity peak on the longer wavelength side. As a result, the ratio of the short circuit currents from both changes proportionally to the incident light wavelength. As shown in FIG. 10A, in the actual circuit, the color signal V _C is obtained by performing the logarithmic compression by the logarithmic compression circuits 104 and 105 and then taking the difference by the subtraction circuit 106. In addition, the current expansion circuits 107 and 108
After being re-expanded by (1), addition is performed by the addition circuit 109, and the luminance signal V _B is obtained through the current-voltage conversion circuit 110. In addition to this, the RGB three primary color filters are SP
Those provided by the filter-chip technique on C have been put to practical use, for example, as a luminance signal Σ (V R ₊ V
_G + _V B), such _lnV R _{-lnV B} as the color signal can be used.

Below, according to the flow chart of FIG.
In particular, the method of determining the photographing light source will be described in detail.

In FIG. 11, first, the SW1 is on standby (step 201, hereinafter abbreviated as S201). SW1 O
Depending on N, the process proceeds to S202. However, the normal shooting sequence (distance measurement / photometry) is omitted here. Next, the luminance signal V _B and the color signal V _C in the light receiving range of the colorimetric sensor in the three directions are sequentially captured (S202). In the area between A and C in the figure, the light receiving range having the highest luminance signal V _B is determined as the photographing light source, and the light source type is determined based on the color signal V _C of the light receiving range, which will be described in detail later. Then, the light source type determined in S203 is coded in the form of data to be written on the film and stored in a buffer (S20).
4). Here, it is confirmed again that SW1 is ON (S205),
If it is OFF, return to the start, if it is ON,
The process proceeds to the next S206, and the SW2 is in a standby state. SW2
The release sequence after turning ON will be described later.

Next, the light source determination sequence of FIG. 12 will be described. Color signal V of the colorimetric sensor described in FIG.
_{Since C} outputs a voltage proportional to the dominant color of the light source color, its intensity is tungsten light <daylight <fluorescent lamp, exactly,
The permutation corresponds to red <yellow <green. Therefore, the switching voltage between tungsten light “T” and daylight “D” is set to V _T , daylight “D”.
And the switching voltage of the fluorescent lamp "F" and _{V F.} The order of this voltage depends on the spectral sensitivity characteristic of each light receiving element in the sensor, and the method described here is not necessarily definitive.

The actual sequence will be described below. By S301 to S306, the photographing light source determination means,
Each of S307 to S311 constitutes a light source color determination unit.

Luminance signal of (output having light receiving range behind)
Issue V_B1And (luminance output above)
Issue V_B2(S301) and V_B1If large, S302
To V_B2If so, go to S303. V_B1If large, next
The luminance signal V of_B1And (output with a light receiving area in front
Intensity) V signal_B3(S302) and V_B1Big
Then go to S304, V_B3If so, go to S303. Furthermore
And V in S301 _B2Large, V in S302_B3At the time of
Luminance signal V_B2Luminance signal V_B3(S30
3), V_B2If large, go to S305, V_B3If large, S
Proceed to 306.

When V _{B1 is the} maximum, the color signal V _{C is set} to the color signal V _C1 (S304).

When V _{B2 is the} maximum, the color signal V _C is set as the color signal V _C2 (S305).

When V _{B3 is the} maximum, the color signal V _{C is set} to the color signal V _C3 (S306).

Next, the color signal V _C determined in S304 to 306 is compared with the switching voltage V _F of the fluorescent lamp F (S30).
7) If the color signal V _C is small, proceed to S308, and if it is large, proceed to S309. When V _{C is} small, the color signal V
The switching voltages V _T of _C , tungsten light and daylight are compared (S
308), if V _C is small, go to S310, and if V _C is large, S
Proceed to 311. As a result, since V _C > V _F , the light source color is determined to be the fluorescent lamp “F” (S309). Also, V _C
<If a _{V T,} the light source color is determined that the tungsten light "T" (S310), _further, if a _{V T <V C <V F} , the light source color is determined as daylight "D" (S311) .

As described above, the light source information with the highest brightness is determined to be the photographing light source, this sequence ends, and the process returns to the main sequence.

Next, the release sequence will be described with reference to FIG. When the switch SW2 is turned on, the shutter 3 is opened and exposure is started (S401). C
The shutter is opened until a close signal is generated from PU, and is closed by the close signal (S402). After closing the shutter, film feeding is started, and at the same time, the pad 11 is pressed against the head H (S404). During this time, the light source color information accumulated in the buffer 23 is passed through the head amplifier 19 to the head H.
And is written on the film F (S405). After that, one frame is detected (S406), whereby the head is retracted (S407) and the film feeding is stopped (S408).

Here, an example of magnetic recording is shown as a method of recording the light source information on the film, but instead of this recording,
As is apparent from the already known recording technology, it is also possible to perform optical recording by using an LED or the like.

As described above, in the conventional example, since the light source color of the light source having the highest brightness can be selectively detected, it is possible to detect only the light source having a large influence by subjecting the object illumination light. is there.

[0020]

In the above-described conventional example, since a plurality of colorimetric sensors are required, the cost is high and the camera is large.

The present invention has been made in order to solve the above-mentioned conventional problems, and is a camera having a simple device having only one colorimetric sensor and having means capable of accurately determining the type of light source. The purpose is to provide.

[0022]

In order to achieve the above object, the camera of the present invention is characterized in that, in claim 1, a light projecting means for projecting light on an object, a color measuring means, and an output of the color measuring means. 3. A camera having a light source type determining means for determining a light source type, wherein the light source type when the light is projected by the light projecting means and when the light is not projected is determined from the output of the colorimetric means. In the light source type determining means, the means for inhibiting the light emission of the light emitting means is provided, and the light emission at the time of color measurement is not performed by the means. According to claim 4, the distance measuring means is provided, and the light projecting means does not emit light by the output of the distance measuring means. In claim 5, the light measuring means and the distance measuring means are provided. The output of the photometric means and the output of the distance measuring means The camera of the present invention has the light source type determining means for determining the light source type based on the output of the means, and the light emitting means in claim 6 also serves as the red eye phenomenon mitigating light emitting means. According to a seventh aspect of the present invention, there is provided a means for determining that there is a possibility of an error in the determination of the light source type, and a recording means for recording the result of the determination means. In the eighth aspect, the output of the photometric means is constant. When the brightness is equal to or higher than the brightness, a means for determining that it is daylight is provided. Further, the light projecting means of the present invention is the light source type judging means for judging the light source of the light projecting means. Is transmitted to the light source type determining means.

[0023]

In the present invention, since one colorimetric sensor is used, the photographing light source is detected based on the distance measurement / photometric information of the object and the difference in the colorimetric sensor output with and without the strobe light. Therefore, the light source type of the subject can be accurately determined.

[0024]

1 to 3 show a first embodiment of the present invention.

FIG. 1 corresponds to FIG. 8 of the conventional example.
It is a perspective view which shows the main structures of a camera. The difference is that the number of photometric sensors S is one and that the strobe 24 is added. In most recent cameras, the strobe 24 is built in the camera body, but in the present embodiment, a built-in strobe or an external strobe may be used.

FIG. 2 corresponds to FIG. 9 of the conventional example.
It is an electric circuit block diagram of a camera. The difference is that the number of photometric sensors S is one and that the strobe 24 and strobe circuit 25 are added.

FIG. 3 is a diagram showing a flow chart of this embodiment. The operation of this embodiment will be described below with reference to the flowchart of FIG. First, it is detected whether the switch button 16 is pressed and the switch 1 is turned on (S502). Next, the flash information is read (S503). Here, strobe information such as the strobe guide number, strobe emission color, and strobe charge state is transmitted to the CPU. In a camera with a built-in strobe, a strobe guide number and strobe emission color information (color information) are stored in a memory circuit in the CPU. The charge status of the strobe is the strobe circuit 2
Get information by communicating with 5. Further, in the external strobe, all information such as the strobe guide number, strobe emission color, strobe charge state, etc. is transmitted from the strobe circuit 25 to the CPU.

The reach of the strobe light can be known from the guide number of the strobe. In addition, the effect of strobe light on the photograph can be seen from the color of the strobe light. further,
Since the color of the strobe light changes depending on the state of charge of the strobe, the effect of strobe light on a photograph can be similarly understood.

Next, after reading the strobe information, the distance measuring block 6 measures the distance to the subject (S50).
4). Next, the brightness of the subject is measured by the photometric block 4 (S505). Then, if the subject is very bright according to the photometric information of the photometric block 4 (S506), it is determined that the shooting is under outdoor daylight (S517), and S518.
Go to. This condition determination can be performed in combination with the clock function built into the CPU and "when the sunlight is sufficiently present and very bright". Also, if the subject is not very bright, as explained in the conventional example,
Color measurement is performed (S507). However, the number of colorimetric sensors is one.

Next, it is detected whether the SW2 (18) is ON (S508), and if the SW2 (18) is ON, the photographing operation is performed. Therefore, it is detected whether the strobe enable switch 26 is ON (S509). When the strobe enable switch 26 is ON, the strobe circuit 25 does not cause the strobe 24 to emit light.

Further, it is determined from the distance measurement information obtained in S504 whether or not there is a subject within the reach of the strobe light (S510). When the subject is outside the reach of the strobe light, the strobe 24 is not fired. If it is within the strobe reach, the strobe 24 is made to emit light for a time determined by the distance measurement and photometry information (S511). Also,
This light emission is also effective for alleviating the red-eye effect, and conversely, color measurement can be performed in S512 during the red-eye effect alleviating light emission. Then, while the flash 24 is emitting light, color measurement is performed (S
512). Next, a release sequence is performed (S51
3). While taking the lens position signal from the encoder by the lens driving actuator 2, the photographing lens 1 is driven according to the distance measurement information. Next, the shutter 3 is opened, the strobe light 24 is emitted depending on conditions, and the shutter 3 is closed after a lapse of a certain time. Then, colorimetric calculation is performed (S514).

Now, let us consider the case of strobe light emission in S511. The colorimetric signal of S507 is V _C1 and the colorimetric signal of S513 is V _C2 . For example, when the color of the subject is white and the light source is a fluorescent lamp, V _C1 > V _F , V _F > V _C2 > V _T , and V
The _C1 -V _C2> 0. When the color of the subject is white and the light source is tungsten light, V _C1 <V _T , V _F > V _C2 > V _T and V _C1 −V _C2 <0. When the color of the subject is white, the colorimetric signal V _{C1 of} S507 may be used, but since the camera does not have means for detecting the color of the subject, in the following cases, V _C1 alone is used. Make an error.

For example, when the subject color is green and the light source is daylight,
V _C1 > V _F , V _C2 > V _F , V _C1 −V _C2 ≈0, and it is judged that only V _C1 is a fluorescent lamp color, but V _C1 and V _C2
By using and, the daylight color can be accurately determined. At this time, the difference between V _{C1 and} V _C2 changes depending on the light amount ratio between the external light and the strobe light and the distance to the subject. Therefore, these conditions are also included in the calculation. Conversely, when the color of the subject is red and the light source is daylight, V _C1 <V _T , V _C2 <V _T , V _C1 −V _C2 ≈0
Therefore, it is possible to accurately determine that the daylight color is a portion that is erroneously determined to be tungsten light only with V _C1 . Therefore, S51
At the time of recording in 5, the light source detection accuracy information and the detected light source type information are recorded. Since the light source detection must be performed only from V _C1 when the flash is turned off, S515
The information about the possibility of erroneous light source detection is recorded at the time of recording.

As the recording sequence, the film is advanced by one frame until the fixed length detection is performed. At this time,
The coded light source information from the buffer 23 is sent to the head H via the head amplifier 19 and recorded on the track T on the film F (S515). In step S506, if the subject is extremely bright according to the photometric information of the photometric block 4, the colorimetric detection is set to daylight (S517). At this time S51
In the colorimetric calculation of 4, the daylight remains as it is. S518 is S5
SW2 (18) is detected as in 08. SW2 (1
If 8) is ON, the process proceeds to the release sequence of S513.

FIG. 4 is a diagram showing another embodiment of the first embodiment, which is the same as the flowchart of FIG. 3 except that the determination in S506 is omitted, and the description thereof will be omitted.

5 to 7 show a second embodiment of the present invention. This example is an example of a camera having no distance measuring device.

FIG. 5 is a perspective view of the main components of the camera and corresponds to FIG. 1 of the first embodiment. The difference is that the distance measuring block 6 and the lens actuator 2 are eliminated and a finder 27 is added.

FIG. 6 is a block diagram of an electric circuit.
Corresponding to. The difference is that the distance measuring block 6 and the lens actuator 2 are eliminated.

FIG. 7 is a flow chart showing the operation of the second embodiment. Hereinafter, a description will be given according to the flowchart of FIG.

First, SW1 is detected (S602).
If SW1 is ON, the brightness of the subject is measured by the brightness signal V _B1 of the photometric sensor 4 or the colorimetric sensor S (S6
03), the color signal V _C1 of the color measurement sensor S is measured (S60
4). Next, SW2 is detected (S605). SW2 is O
If the strobe enable switch 26 is ON and the strobe enable switch 26 is ON, the strobe light is not emitted and the process proceeds to S610. Also,
If the strobe enable switch 26 is off, the strobe 24 is illuminated (S607). And strobe 2
The luminance signal V _B2 of the subject during the emission of 4 is S603.
The same measurement is performed (S608). Further, the color signal V _C2 of the subject while the strobe 24 is emitting light is measured in the same manner as in S604 (S609).

Next, the shutter is opened, and the shutter is closed after a lapse of a fixed time determined by the photometric information in S603 (S6).
10). The colorimetric calculation is performed in the same manner as S514 (S611).
But if you did not emit strobe 24, when the difference between the photometric output V _B2 of the photometric output V _B1 and S608 in S603 is small, i.e. when the emitted light of the flash 24 does not reach the subject , The colorimetric error possibility information is recorded together with the light source type information. In this way, whether or not the strobe light has reached the subject is determined based on the photometric information when the strobe light is emitted and when the strobe light is not emitted. Then, recording is performed similarly to S515 (S612).

[0042]

As described above, since the present invention is provided with only one colorimetric sensor, the apparatus is simple and can be manufactured at low cost, and the colorimetric information when the strobe emits light and when it does not emit light. From this difference, it is possible to accurately determine the light source type of the subject.

[Brief description of drawings]

FIG. 1 is a perspective view showing the main configuration of a camera that is a first embodiment of the present invention.

2 is a block diagram of an electric circuit of the camera of FIG. 1. FIG.

FIG. 3 is a flowchart showing the operation of the embodiment of FIG.

FIG. 4 is a flowchart showing the operation of another embodiment of FIG.

FIG. 5 is a perspective view showing a main configuration of a camera of a second embodiment of the present invention.

6 is an electrical block diagram of the camera of the embodiment of FIG.

7 is a flowchart showing the operation of the embodiment of FIG.

FIG. 8 is a perspective view showing a main configuration of a conventional camera.

9 is an electrical block diagram of the conventional camera of FIG.

FIG. 10 is a block diagram showing a main configuration of a colorimetric sensor.

11 is a flowchart showing the operation of the conventional example of FIG.

12 is a flowchart showing the operation of the conventional example of FIG.

13 is a flowchart showing the operation of the conventional example of FIG.

[Explanation of symbols]

 1 Photographic lens 2 Lens actuator and lens encoder 3 Lens shutter 4 Photometric sensor 5 Lens 6 Distance measuring block and finder block 7 Photoreflector 8 Film feeding motor 9 Gear train 10 Rewinding fork 11 Crimping pad 12 Pad retracting mechanism 15 White diffuser plate 16 Release Button 17 SW1 18 SW2 24 Strobe 25 Strobe Circuit 26 Strobe Enable Switch 27 Finder Block FC Film Cartridge F Film P1, P2 Perforation H Magnetic Head S Colorimetric Sensor M Colorimetric Circuit

Claims (9)

[Claims] 1. A camera having a light projecting means for projecting light onto an object, a color measuring means, and a light source type determining means for determining a light source type based on the output of the color measuring means, the output of the color measuring means. From the above, the camera determines the light source type from the output of the colorimetric means when the light is projected by the light projecting means and when it is not projected. 2. The camera according to claim 1, further comprising means for prohibiting the light projection of the light projection means, and the light projection at the time of color measurement is not performed by the means. 3. The camera according to claim 1, wherein the light source type determination means has color information of a light source to be projected. 4. The camera according to claim 1, further comprising distance measuring means, wherein the light projecting means does not emit light by the output of the distance measuring means. 5. The camera according to claim 1, further comprising a photometric means and a distance measuring means, and a light source type determining means for determining a light source type based on the output of the photometric means, the output of the distance measuring means and the output of the color measuring means. A camera characterized by that. 6. The camera according to claim 1, wherein the light projecting means is also used as the red eye phenomenon mitigating light projecting means. 7. A camera having a light projecting means for projecting light on an object, a color measuring means, a light source type determining means for determining a light source type based on the output of the color measuring means, and a light measuring means.
A camera comprising means for determining that there is a possibility of an error in the determination of the light source type, and recording means for recording the result of the determination means. 8. A camera having a light projecting means for projecting light on an object, a color measuring means, a light source type determining means for determining a light source type based on the output of the color measuring means, and a photometric means.
A camera provided with means for determining that it is daylight when the output of the photometric means is above a certain brightness. 9. A light projecting means for projecting light onto an object, to a light source type judging means for judging a light source of the light projecting means, and transmitting color information projected by the light projecting means to the light source type judging means. A means for projecting light.