JPH0685040B2 - Camera data capture device - Google Patents

Description

The present invention relates to a camera having a data imprinting device capable of recording necessary data on a film screen simultaneously with an image.

In various fields, there is a demand for recording an image to be recorded and data related to the image on the same film screen. This is because if the data necessary for recording is left in a part of the screen, the necessary data is reproduced at the same time when the screen is reproduced, which is convenient.

Therefore, various data simultaneous image capturing devices have been proposed, but it is difficult to adjust the data exposure when the conditions of the brightness of the subject in the data image capturing part are changed, and it is difficult to record high quality data. There was a problem.

An object of the present invention is to provide a data imprinting device for a camera, which can always record data clearly by adjusting the illumination of the data following the change in the brightness of the subject in the data imprinting part. To provide.

According to the present invention, the difference between the proper exposure amount of the subject and the exposure amount of the data imprinting section is obtained, and the brightness of the data imprinting section on the photographic film from the latitude center of the film, that is, The above-mentioned object is solved by providing a device for knowing how many steps are offset and by using this, always captures data with a light quantity that is k steps more than the subject light quantity in the data section.

Hereinafter, the present invention will be described based on examples.

FIG. 1 shows a shooting screen 1 of the camera and a data copying unit 2 in which shooting data such as a date, a date, and the like should be copied.

FIG. 2 shows an embodiment of the data imprinting device according to the present invention. In the present embodiment, the case is applied to a so-called multi-photometry method in which the subject brightness is measured at each part of the photographing screen divided into a plurality of parts to calculate the proper exposure. Light receiving elements PD _{1 to} PDn are arranged at predetermined positions in order to measure the brightness of each part of the photographing screen 1. The light receiving element PDn is arranged at a position where the brightness of the data capturing unit 2 is measured. Switch
When S ₁ is connected to the terminal b side, the anode of the photodiode PDn, which is a light receiving element, is also grounded, and all the light receiving elements PD _{1 to} PDn are in a state of measuring the brightness of each part of the photographing screen 1. With operational amplifiers A _{1 to} An and diodes D _{1 to} Dn
The outputs of PD _{1 to} PDn are logarithmically compressed and input to the multiprocessor MP. In the multi-processor MP, these plural inputs are processed so as to obtain the optimum exposure condition, and finally output from the multi-processor MP as the proper subject light amount signal voltage V _MP . This object light quantity signal voltage V _MP is the switch S ₂
It is charged to the capacitor C ₁ via and is input to the exposure control system EX through the buffer amplifier B ₃ . Exposure control system EX
In step 1, the exposure is controlled so that the brightness corresponding to the input subject light amount signal is at the center of the latitude of the photographic film. In this way, proper exposure shooting is performed by multi-photometry of the subject.

Next, connect switch S ₁ to the terminal a side, and
Release S ₂ . When the switch S _{2 is} opened, it is stored in the object light amount signal voltage V _MP capacitor C ₁ based on the previously measured multi-photometric information of the object. When the switch S ₁ is connected to the terminal a side, it is biased by the output voltage of the anode buffer amplifier B ₁ of the photometric light receiving element PDn of the data capturing unit 2. The output voltage of the buffer amplifier B ₁ is the power supply voltage V
It is defined by the variable resistor VR ₁ for setting the film ASA information connected to the power line L of the _CC and the adjusting resistor VR ₂ for copying the data to the k-th stage over by the latitude center of the film. Therefore, the output of the operational amplifier An forming the logarithmic compression amplifier is the sum of the ASA information, the k-stage over information, and the brightness information of the data imprinting section, and this output (V _ASA + Vk + V _A n) buffer amplifier B ₂ Applied to the non-inverting input terminal of. The buffer amplifier B ₂ is an operational amplifier, the output terminal of which is connected to the base of the transistor Tr ₁ , and the inverting input terminal of which is connected to the transistor emitter. The power supply voltage V _CC is applied to the collector of the transistor Tr ₁ by a resistor R ₁ which is a load. Since the input side of the operational amplifier B ₂ has a state of imaginary short-circuit, the voltages at the two input terminals are substantially equal. Therefore, the output voltage V _ASA + Vk + V _A n of the buffer amplifier An applied to one input of the operational amplifier B ₂ and the transistor Tr ₁
The potentials of the emitters are substantially equal. Transistor Tr ₁
The emitter of is connected to the output of a buffer amplifier B ₃ via a resistor R ₂ . In the buffer amplifier B ₃ , the inverting input terminal is directly connected to its output terminal to form a voltage follower, and its gain is 1. Therefore, the potential V _MP of the capacitor C ₁ appears at the output terminal as it is. Therefore, the voltage across the resistor R ₂ is as follows.

Exposure of a subject is determined by _{(V ASA + Vk + V A} n) -V MP = V ASA + Vk (V A n-V MP) Multichannel photodetector voltage V _MP exposure control system should come film La Chichi user de center relative EX because they are, the voltage (V _a n-V _MP) represents the degree of deviation from La Chichi Yu de center of the data imprinting section, i.e. the number of stages. In other words, the voltage V _A n-V _MP indicates whether the brightness of the subject in the data projection area is brighter or darker than the average brightness of the entire screen when the proper exposure is shot with the multi-metering voltage V _MP. There is. If V _A n = V _MP and the brightness of the data recording part of the photographed subject is in the latitude center, the voltage across resistor R ₂ will be V _ASA + Vk, and data will be taken for the time based on this voltage. Projection light source LED
By turning on and exposing the part further, the data contents can be brightened by k steps brighter than the Tachi-Tude Center, and the data contents can be brightened k steps brighter than the background to distinguish the data contents from the background. can do. If V _A
If n> V _MP and the brightness of the captured data of the subject is 1 step brighter than the latitude center, resistance
The voltage across R ₂ is V _ASA + Vk + Vl (however, Vl = V _A n −V _MP ), and the data-imprinted light source LED is only for the period based on this voltage.
If is turned on and the part of the data content is further exposed, the data content is read from the latitude center (k + 1).
By projecting only the steps brighter, the data content can still be projected k steps brighter than the background to be distinguished from the background. That is, if the data projection light source LED is turned on at a time corresponding to the voltage generated in the resistor R ₂ and the data exposure is further exposed to the subject exposure of the data projection section, the data is always brighter by k steps than the background of that section. It will be reflected.

A circuit for controlling the lighting time of the data imprinting light source LED based on the voltage across the resistor R ₂ will be described. The emitter current and the collector current of the transistor Tr ₁ are almost equal. Therefore, the voltage across the resistor R ₂ is multiplied by R ₁ / R _{2 and} appears as the voltage across the resistor R ₁ . This voltage charges the capacitor C ₂ via the switch S ₃ as a buffer amplifier having a gain of 1. The charging voltage of the capacitor C ₂ is applied to the positive input terminal of the comparator CP. Switch S ₅ that is inserted into the data imprinting light source LED series is normally open, switch which is short-circuited through the current limiting resistor R ₃ and capacitor C ₃
S ₄ is normally closed. In this state the comparator
The potential of the negative input terminal of CP is higher than the potential of the positive input terminal, the output potential of the comparator CP is at Low level, the PNP transistor Tr ₂ is ON, but the switch S ₅ is open, so the light source LED is lit. Not not. Now, suppose switch S ₅ is closed together with switch S ₄ . Since the transistor Tr ₂ is turned on, the light source LED starts lighting by closing the switch S ₅ . When the switch S _{4 is} opened, the capacitor C ₃ is charged with the current flowing through the diode D ₀ . The diode D ₀ gives linearity to the relationship between the charging voltage of the capacitor C ₃ and time. Charging voltage capacitor of the capacitor C ₃ C ₂
When it becomes equal to the charging voltage of, the output of the comparator CP is inverted, the transistor Tr ₂ is turned off, and the data-imprinted light source LED is turned off. That is, the lighting time of the light source LED can be made to depend on the charging voltage of the capacitor C ₂ , and thus the voltage across the resistor R ₂ .

The flow of opening and closing the switch at the time of shooting will be described. First, the shutter button is pushed down, and the shutter is released. At this time, the switch S ₂ is closed and the switch S ₁ is connected to the terminal b side, whereby the multi-photometric proper exposure for the subject is determined and the subject is exposed. Next, the switch S ₂ is opened, the multi-photometric voltage V _MP is stored in the capacitor C ₁ , and the connection of the switch S ₁ is switched from the terminal b side to the terminal a side. Thus lighting time control voltage of the data imprinting light source is generated across the resistor R _2, switch S ₃ and the voltage after a lapse of time obtained by _doubling R ₁ / R is charged reliably in the capacitor C ₂ is open The data imprinting light source lighting time control voltage is stored. Next, the switch S ₄ is opened and the switch S ₅ is closed, so that the data-imprinting light source LED starts lighting. The light source LED is turned off after the data-imaging light source lighting time has elapsed, and proper data imprinting is completed.

In the above-mentioned embodiment, the data content is written on the transparent sheet, and the method of illuminating and burning this with one LED has been described as an example, but the LED itself is a 7-segment type. Even in the method of displaying the data by selective driving and printing the data on the photographic film, it is possible to control the lighting similarly. Further, there is no problem even if other light source such as a lamp is used instead of the LED. In the present invention, a circuit for controlling the light emission time according to the brightness of the data imprinting section,
The present invention extends to all data imprinting means applicable to the present invention.

In the above-described embodiment, the data imprinting section of the photographing screen is measured by one light receiving element, but as shown in FIG. 3, for example, three light receiving elements D _{3 to} D ₅ are provided to make the data imprinting section 3 It can be divided. In this case, when you want to capture a 6-digit number such as the date or the date and time, the metering element D ₃ is used to measure the part of the image where the year or the day is captured. performs photometry of the photometry part to be written D ₄ a and day or partial copies in D _5, it is possible to perform the data imprinting exposure suitable in each. In this case, a plurality of control circuits shown in FIG. 2 can be used depending on the number of light receiving elements, but the circuit configuration can be simplified by dynamically driving the input and output in the same circuit.

The multi-photometric method related to the above-described embodiment of the present invention will be described below. FIG. 4 is a block diagram showing an embodiment of an exposure control circuit including a multiprocessor. In the figure, the photometric circuit 10 includes a photoelectric conversion element for photometrically measuring each area obtained by dividing the object scene into a plurality of areas, and outputs independent analog photoelectric outputs Po to Pn corresponding to the respective areas of the object scene. It is assumed that the photoelectric outputs Po to Pn are logarithmically compressed, so that the photoelectric pressure is represented by the BV value. The maximum value detection circuit 11 receives the photoelectric outputs Po to Pn as inputs, and detects the maximum value Pmax from these.

The average value detection circuit 12 receives the photoelectric outputs Po to Pn as inputs, and detects the average value of these, for example, the average value Pmean. The minimum value detection circuit 13 receives the photoelectric outputs Po to Pn as inputs and detects the minimum value Pmin from them. The arithmetic circuit 14 receives the maximum value Pmax and the average value Pmean as inputs and generates a first photometric output PH (BV), that is, PH = k ₁ Pmax + (1-k ₁ ) Pmean (1). The arithmetic circuit 15 generates the second photometric output PM (BV), that is, PM = Pmean (2), but can actually be used also as the average value detection circuit 12. The arithmetic circuit 16 inputs the minimum value Pmin and the average value Pmean and generates a third photometric output PL (BV), that is, PL = k ₂ Pmin + (1 + k ₂ ) Pmean (3). The circuits 11 to 16 described above form a proper photometric output generation circuit.

The binarization circuit 17 is a part for performing standardization, and the photoelectric output Po
~ Pn and the average value Pmean are input, the reference output generated based on the average value Pmean and the photometric output Po ~ Pn are compared,
Each photoelectric output is converted to a logical output. Specifically, in the embodiment, the output Pn at the n-th position and the average value Pmean are compared, and Pn ≧ Pmean is set to 1 and Pn <Pmean is set to 0. If the standardized output is 1, it means that the n-th position is a brighter part than the average, and if it is 0, it is a darker part. That is, the above-mentioned standardization takes the form of binarization.

Alternatively, the following can be done. Average value to divide the overall brightness into bright, dark and middle parts
Pmean + δH, Pmean−δL as the reference output based on Pmean
For each of these two reference levels.
This is a method of digitization. That is, 1 when Pn> Pmean + δH holds, 0 when Pn ≦ Pmean + δH holds, and 1 when Pn ≧ Pmean−δL holds, Pn <Pme
Set to 0 when an-δL. In this case, the binary output at the n-th position is two (2 bits).

When the outputs are arranged in the order of comparison of Pmean + δH and Pmean−δL, if the output is 11, the bright part is shown, 00 is the dark part, and 01 is the part close to the mean value of the middle (10
Does not exist). By dividing the brightness of the position into three levels in this way, a more sophisticated pattern analysis becomes possible.

Of course, the binarization circuit can be divided into four or more stages, and the division method may be changed according to the position.

Next, the first judgment circuit 18 receives the maximum value Pmax as an input and makes a judgment of Pα ≦ Pmax ≦ Pβ (where Pα and Pβ are constants) (4) and generates a logical output representing the judgment result. . Of course, the first determination circuit 18 includes a circuit that generates reference outputs corresponding to Pα and Pβ. This determination operation is performed to identify whether the maximum value Pmax is caused by a bright light source including the sun or an artificial light source such as a spotlight. The second determination circuit 19 inputs the maximum value Pmax and the minimum value Pmin and performs the operation of ΔP = Pmax−Pmin (5), and then α ≦ ΔP ≦ β (where α and β are constants). The determination of (6) is performed and a logical output representing the determination result is generated. Of course, the circuit for generating the reference output corresponding to the constants α and β is included in the second determination circuit 19. This judgment operation judges the brightness distribution in the screen, and when the main subject is on the low brightness side when the brightness distribution is large, for example, when the exposure is adjusted to the low brightness side, the high brightness side is skipped, and vice versa. This is performed in order to prevent a phenomenon that occurs when the main subject is on the high-luminance side and when the exposure on the high-luminance side is adjusted to the low-luminance side.

The classification circuit 20 receives the logic outputs from the circuits 17, 18, and 19 as input, and determines which of the predetermined categories the combinational logic of these logic outputs belongs to, that is, the classification. This predetermined category is divided into three, and the control output corresponding to each category is selectively generated. The analog switches 21, 22, 23 respectively connected between the circuits 14, 15, 16 and the apex operation circuit 24 are classified by the control output of the classification circuit 20 from the first to third photometric outputs. The output corresponding to the selected category is selected and transmitted to the apex operation circuit 24.

The aperture calculation circuit 24 generates an output corresponding to an appropriate exposure value (shutter speed or aperture value) according to the selected photometric output and other exposure factors from the information setting section 27, and outputs this output to a known exposure value. It is applied to the control circuit 25 and the exposure display circuit 26.

Next, the mode of classification by the classification circuit 20 along with the operation will be described for the case where the screen is divided into three and five parts and photometry is performed. FIGS. 5 (a) and 5 (b) show the division status of the screen and the photoelectric output of each divided area.

(1) In FIG. 5 (a), the screen is divided into a central area Dc, an upper area Du, and a lower area Dl, assuming a 6 × 6 format camera, and the photoelectric output of each is represented by Po to P _2. ing.

Each photoelectric output Po to P ₂ has an average value Pmean (= (P ₀ + P ₁ + P ₂ ) /
3), each region is represented by a logical value of 1 when P _{0 to} P ₂ ≧ Pmean and is represented by a logical value of 0 when P _{0 to} P ₂ <Pmean. The classification circuit 20 has this combination of logical values,
(I) When the central area Dc is 0 or the lower area Dl is 0 (because the main subject is likely to be present in the area Dc or Dl at this time), the analog switch 23 is turned on and the third
The photometric output PL of is transmitted to the apex operation circuit 24. (I
i) When the central area Dc is 1 (at this time, the main subject is the area D
analog switch 21 because it is more likely to be present in c)
Is turned on and the first photometric output PH is set to the apex calculation circuit 24.
Communicate to.

On the other hand, the first determination circuit 18 outputs a logical value 1 when Pα ≦ Pmax ≦ Pβ, and outputs a logical value 0 in other cases. The second determination circuit 19 outputs the logical value 1 when α ≦ ΔP ≦ β,
Otherwise, a logical 0 output is generated. Then, when the logical value 1 is applied from the first and second determination circuits 18 and 19, the classification circuit 20 gives priority to this even if the screen is in the above states (i) and (ii). , Analog switch 22
Is turned on and the second photometric output PM is set to the apex calculation circuit 24
Communicate to.

(2) In Fig. 5 (b), the screen is divided into a central area Dc, an upper right area Dru, an upper left area Dlu, and a lower left area Dll, assuming that a Leica camera is used, and each photoelectric output is P ₀
It is represented by ~ P ₄ . Each photoelectric output P _{0 to} P ₄ is compared with the average value Pmean as described above, and each region is represented by a logical value 1 or 0.

The classification circuit 20 has this combination (i) when the central area Dc is 0, or the left and right lower areas Dll and Drl are 0, or the upper left area Dlu and the lower left area Dll are 0, or the upper right area. When the direction area Dru and the lower right area Drl are 0, the analog switch 23 is turned on (because the main subject is likely to exist in the area of 0 at these times) and the third photometric output PL is set to the apex operation circuit. Communicate to 24. Other than this, the operation is the same as that described in the item (1). This example of 5 divisions considers that there are vertical and horizontal shooting positions like a Leica camera.

The photometric output calculated and extracted in this way is subjected to the Apex calculation and applied to the exposure control circuit 25 and the exposure display circuit 26. In this embodiment, the apex operation is performed after the photometric output is extracted, but the present invention is not limited to this, and the photoelectric output may be immediately subjected to the apex operation and transmitted to the circuits 11 to 13, 17. . At this time, the level of the output after performing the Apex operation on the plurality of photoelectric outputs changes, but the magnitude relationship between the levels does not change, so that the same operation as described above can be performed. And the 1st to 3rd photometric outputs are based on the BV value.
It shows TV value or AV value.

Further, in the present embodiment, the first to third photometric outputs are calculated and the calculation results are extracted, but the same thing can be done by selecting the calculation formulas of the formulas (1) to (3), for example. Can be achieved. This is because it is only necessary to select any one of the first to third photometric outputs as a result.

Further, the standardization is not limited to the one in which the photoelectric output is replaced with two levels. For example, by providing two reference levels near the average value and binarizing each photoelectric output for each reference level. , The photoelectric output near the average value may be replaced with another level.

In the above embodiment, the elements PDn, An, Dn are photometric means, and the elements B1, B2, B4, C2, C3, CP, LED1, R1, S3 to
S5, Tr1, Tr2, VR1 and VR2 respectively constitute control means.

As described above in detail, according to the present invention, since the data to be imprinted in the data imprinting section can be imprinted with an exposure amount larger than that of the subject image formed in the data imprinting section, The embedded data will not be indistinguishable due to the subject image overlapping with this.

[Brief description of drawings]

FIG. 1 is a diagram showing a photographing screen and a data imprinting unit which are objects of the present invention, FIG. 2 is a circuit diagram of an embodiment of a data imprinting device according to the present invention, and FIG. 3 is a data imprinting unit divided into three parts. FIG. 4 is a block diagram of the multi-photometric system in the embodiment shown in FIG. 2, and FIG. 5 is a diagram showing how the photographing screen is divided in the multi-photometric system shown in FIG. . <Explanation of symbols of main parts> Means for measuring the brightness of the data imprinting portion ・ ・ ・ PDn Means for adding a constant ...... VR ₁ , VR ₂ , B ₁

Claims (4)

[Claims] Claims: 1. A subject in a photographing screen is metered to obtain a first photometric output, and an exposure amount is controlled based on the first photometric output to photograph a subject with a proper exposure. In a camera that captures desired data in a data imprinting section formed in one corner of the area, photometers an area in the shooting screen that substantially coincides with the data imprinting section, and outputs a second photometric output for a subject in the area. Photometric means (PDn, An, Dn) for obtaining and predetermined value output means (VR for outputting a signal corresponding to a predetermined value)
2) and, based on the output obtained by adding the predetermined value to the output difference between the second photometric output and the first photometric output, the exposure of the data projection is higher than the exposure amount of the subject located in the data projection unit. The control means (B1, B2, control means for controlling the exposure amount of the data imprinting so that the amount is always increased by the amount corresponding to the predetermined value.
B4, C2, C3, CP, LED1, R1 to R4, S3 to S5, Tr1, Tr2, VR1). 2. A data imprinting device for a camera according to claim 1, wherein said control means is a light emitting means for imprinting data, and an exposure amount of an object located in said data imprinting section. And a means for controlling the light emission time of the light emitting means so that the exposure amount is increased by an amount corresponding to the predetermined value. 3. A subject on the photographing screen is metered to obtain a first photometric output, and an exposure amount is controlled based on the first photometric output to photograph the subject at a proper exposure, while the photographing screen is displayed. In a camera that captures desired data in a data imprinting section formed in one corner of the image capturing screen, the photographing screen is located at least in the central region and in the periphery of the central region, and has an area that is less than a quarter of the photographing screen. Photometric means (PD1, A1, D1, ……… PDn, An, Dn) that obtains multiple photometric outputs corresponding to each area by dividing the photometer into four peripheral areas.
A proper photometric output generating means (MP) for obtaining the first photometric output from the plurality of photometric outputs;
Specific photometric output selection means (B2) for selecting the second photometric output for one peripheral area and predetermined value output means (VR for outputting a signal corresponding to a predetermined value)
2) and based on the output obtained by adding the predetermined value to the output difference between the second photometric output and the first photometric output, the exposure amount of the subject located in the peripheral area including the data imprinting unit The control means (B4, C2, C3, CP, LED1, R1 to R4, S3 for controlling the exposure amount of the data imprinting so that the exposure amount of the data imprinting always becomes larger by an amount corresponding to the predetermined value. ~ S5, Tr1, Tr2, VR
1) A data imprinting device for a camera, which has and. 4. A data imprinting apparatus for a camera according to claim 3, wherein the control means includes a light emitting means for imprinting data and a peripheral area including the data imprinting section. A data imprinting device, comprising means for controlling the light emission time of the light emitting means so that the exposure amount becomes larger than the exposure amount for the subject by the amount corresponding to the predetermined value.