JP4401902B2 - Viewfinder for both monochrome and color display - Google Patents

Description

  The present invention relates to a viewfinder for both monochrome and color display used for broadcast and commercial video cameras.

  Conventionally, since a high-resolution image is required for focusing on a viewfinder used for a broadcast or commercial video camera, a monochrome CRT (Cathode Ray Tube) is used.

  The viewfinder is provided with a black and white CRT serving as a display unit in the case body at a right angle to the optical axis to the eyepiece, and reflects the black and white CRT image on the optical axis to the eyepiece. It has a structure in which a reflecting mirror is provided. Therefore, the photographer can check the photographed image through the image from the reflection mirror by looking into the eyepiece provided in the eyepiece.

  However, the conventional viewfinder using the black and white CRT cannot display a color image. Therefore, it is not possible to check whether the color temperature (white balance) is correct in the adjustment work performed before the start of shooting. Because it had to be confirmed by connecting to a color monitor, it was very time consuming.

  In addition, if the subject's appearance and appearance are similar during shooting, it may be easier to distinguish the subject to be shot by color. In such a case, the conventional viewfinder described above may cause movement of the subject. In some cases, the subject could not be captured.

  Then, it is preferable to display the monitor image in the viewfinder as a color image at all times, although it is suitable for specific cases such as adjustment work before the start of shooting. This makes it difficult to respond. For this reason, a black and white CRT image capable of high resolution display is required.

  Therefore, a technique related to a viewfinder that can be used for both black and white and color display has been proposed. For example, Patent Document 1 describes a viewfinder that can easily display a color image by switching a monochrome CRT video.

  This viewfinder is provided with a high-resolution black and white CRT that displays black and white images taken by a video camera, and a color display panel that displays the shot images in color, and by switching the angle of the reflecting mirror, Either the CRT image or the image from the color display panel is reflected by a reflecting plate and supplied to the eyepiece.

JP 2001-326838 A (the whole specification)

  However, in the above-described viewfinder, the black and white CRT display screen is arranged at a position off the optical axis of the eyepiece, that is, at a right angle in the horizontal plane, and the display surface of the color display panel is also off the optical axis of the eyepiece. Position, i.e., perpendicular to the vertical plane. For this reason, the movement of the reflecting mirror that switches the image supplied to the eyepiece to either the black-and-white CRT or the color display panel is twisted, and the switching mechanism must be complicated, and at the same time the cost increases. It can't be said that no unexpected trouble occurs at the time of switching.

  The present invention has been made in view of the above circumstances, and its object is a viewfinder applied to broadcast and commercial video cameras, which requires black and white CRT and color display panel images. Accordingly, it is possible to provide a viewfinder for both monochrome and color display, which can be switched in accordance with a simple mechanism, has few failures, and is inexpensive.

In order to achieve the above object, the present invention takes the following technical means.
That is, the monochrome / color / color display viewfinder according to claim 1 includes a monochrome display and a monochrome display having a monochrome CRT for displaying an image captured by a video camera and a color display panel for displaying the image in color in the viewfinder case body. A color display combined viewfinder, wherein the monochrome CRT is disposed at a position deviating from the optical axis to the eyepiece, and the color display panel is disposed on the optical axis to the eyepiece, and the viewfinder When selecting a video image to be displayed on the black and white CRT by arranging a reflecting mirror that is pivotally supported by a driving means at one end in the case body, the video image is reflected by the reflecting mirror so that the contact is made. When selecting an image to be supplied to the eye and displayed on the color display panel, the reflector is rotated to a position that does not block the optical axis to the eyepiece. It is characterized in that so as to supply the image directly the eyepiece by.

  According to a second aspect of the present invention, there is provided a viewfinder for both monochrome and color display according to the first aspect of the present invention. It is automatically driven to a position to be selected, and is configured to automatically return to a position to select an image displayed by the black and white CRT after a predetermined time has elapsed when the auto white balance adjustment function is completed.

  Still further, the black and white / color display viewfinder according to claim 3 is the switching detection according to claim 1 or 2, wherein the power to the monochrome CRT and the color display panel detects the switching operation of the reflecting mirror. Controlled by a detection signal from the circuit, the power is automatically turned off on the side of the monochrome CRT or color display panel on which the display image is not selected.

  According to the first aspect of the present invention, since the limited space in the viewfinder case main body is effectively used, the monochrome image and the color display image can be appropriately selected according to the situation with a simple configuration. Focus can be adjusted accurately and high quality images can be taken.

  In the invention described in claim 2, since the color image is automatically selected when the auto white balance adjustment function is executed and can be automatically restored to the monochrome image when the adjustment is completed, there is no troublesome switching operation, Shooting work can be carried out efficiently.

  According to the third aspect of the present invention, the power of the black and white CRT or the color display panel on which the display image is not selected is automatically turned off, so that unnecessary power consumption due to the addition of the display device is prevented. The power consumption can be suppressed to a level that is almost unchanged.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a viewfinder for both monochrome and color display according to the present invention will be described below with reference to the drawings.
1A and 1B show an embodiment of a viewfinder 100 for both monochrome and color display according to the present invention. FIG. 1A is a plan sectional view when an image on a monochrome CRT side is selected by switching a reflecting mirror, and FIG. FIG. 6 is a plan sectional view when the image on the color display panel side is selected by switching the reflector.

In the viewfinder case main body 10 of the viewfinder 100, a black and white CRT 11 for displaying captured images in black and white with high resolution is provided at a position perpendicular to the optical axis 40 to the eyepiece 30. A color display panel 12 is provided on the optical axis 40 to the eyepiece 30.
The video signals supplied to the two displays 11 and 12 should naturally have a smaller number of wires in terms of manufacturing man-hours. Therefore, the ENC (encoder) output signal in the video processing circuit of the video camera main body. Therefore, it is preferable to wire one by one.
Conventionally, the color display panel 12 made up of a liquid crystal unit has a limited input signal format, but now it can display any type of ENC signal, component signal, and RGB signal. Since there are many, the signal is extracted from the ENC output signal that requires the least number of wires.
In addition, since the purpose of providing the color display panel 12 in the present invention is only to confirm the color of the captured video and does not require resolution, the color display panel 12 uses an inexpensive low-resolution one and outputs ENC. If the signal is extracted from the signal, the entire viewfinder device can be constructed at low cost.

The viewfinder case body 10 is provided with a rotation shaft 13 rotatably disposed on the case body 10, and one end portion of a reflecting mirror 14 is pivotally supported on the rotation shaft 13. Thus, the reflecting mirror 14 is also rotated as the rotating shaft 13 is rotated.
As shown in FIG. 1A, the reflecting surface 14 a of the reflecting mirror 14 reflects the display image of the black and white CRT 11 and supplies it to the eyepiece 30 in the normal state. It is arranged at an angle of 45 ° to 40.

  On the other hand, when it is selected to supply the image of the color display panel 12 to the eyepiece unit 30, the rotating shaft 13 rotates and the reflecting surface 14a of the reflecting mirror 14 is shown in FIG. As described above, it is retracted to a position that is parallel to the optical axis 40 and does not block the optical axis 40, and is positioned so as to block the display surface of the monochrome CRT 11.

Next, the rotation control of the reflecting mirror 14 will be described.
FIG. 2 is an electrical block diagram showing an image switching system of the viewfinder for both monochrome and color display according to the present embodiment.
In the figure, reference numeral 21 denotes an AWB execution status signal that is output when an AWB (Auto White Balance) button or the like (not shown) is pressed, 22 is a CPU (Central Processing Unit) that is a control means of the servo motor drive circuit, 23 is a drive circuit for driving a servo motor, 24 is a reflecting mirror changeover switch, 25 is a servo motor as a driving means for moving the reflecting mirror, 11 is a monochrome CRT, 12 is a color display panel, 13 is a rotating shaft, and 14 is a reflecting member. Reference numeral 29 denotes a mirror switching detection circuit.
Here, a range surrounded by a dotted line is the viewfinder unit 20 and is housed in the viewfinder case body 10 in FIG.

  Here, the switching detection circuit 29 of the reflecting mirror 14 detects the switching operation of the reflecting mirror 14 and sends a detection signal to the monochrome CRT 11 and the color display panel 12.

  The operation of the viewfinder for both monochrome and color display according to the present embodiment configured as described above will be described with reference to FIGS. 1 (a), 1 (b) and FIG. As shown in FIGS. 1A and 1B, a black and white CRT 11 and a color display panel 12 are arranged in the viewfinder case body 10 so as to be positioned at right angles to each other.

  Specifically, the monochrome CRT 11 is arranged so as to be positioned at right angles to the optical axis 40 to the eyepiece 30, the color display panel 12 is on the optical axis 40 to the eyepiece 30, and the reflecting mirror 14 is arranged at the back position.

  Since normal focusing requires manual focusing, the reflecting mirror 14 is moved so as to be positioned at an angle of 45 ° with respect to the optical axis toward the eyepiece, as shown in FIG. As a result, the display image of the monochrome CRT 11 is reflected by the reflecting mirror 14, and the monochrome image having a high resolution is supplied to the eyepiece unit 30.

  When white balance adjustment is performed, when an AWB button (not shown) on the video camera body is pressed, an AWB execution status signal 21 is input to the CPU 22 which is a control means. Thereafter, a control signal is sent from the CPU 22 to the servo motor drive circuit 23, and the drive signal is supplied from the servo motor drive circuit 23 to the servo motor 25. As a result, the servo motor 25 is driven, the turning shaft 13 connected to the servo motor 25 is turned, and the reflecting mirror 14 is turned about the left end (see FIG. 1).

  Then, as shown in FIG. 1B, the reflecting mirror 14 does not block the optical axis 40 to the eyepiece 30, and the display image of the color display panel 12 in the back of the mirror 14 directly becomes the eyepiece 30. Will be supplied to.

  As described above, when the AWB button is pressed, the color image can be automatically switched to the color image on the color display panel 12 side, so that the photographer can check whether the color temperature (white balance) is correct without performing troublesome operations. Can be confirmed and adjusted.

  Next, after the white balance adjustment is completed, when a preset time elapses, the monochrome image on the monochrome CRT 11 side is automatically restored. At that time, the display device that is not selected by the reflecting mirror 14 in the monochrome CRT 11 or the color display panel 12 at the time of the switching is automatically turned on when a predetermined time elapses according to a detection signal from the switching detection circuit 29. Is configured to expire. As a result, the power consumption can be suppressed to a level that is not substantially different from the conventional one.

  In addition, the viewfinder unit 20 is provided with a reflecting mirror changeover switch 24 so that the image can be changed manually. When this reflecting mirror changeover switch 24 is operated, a control signal is sent directly to the servo motor drive circuit 23 without going through the CPU 22, so that the control of the CPU 22 can be forcibly cut off and the reflecting mirror 14 can be switched manually. .

  Therefore, it is very useful as a method to check by temporarily switching to color video as a method of distinguishing by color difference when the subject's appearance and appearance are similar at the time of shooting and it is difficult to distinguish in black and white It is.

  In the present invention, when it is desired to check the state of the color temperature of a subject on a video camera, such as accurate focus adjustment and white balance adjustment before photographing, both of them can be effectively performed. It can be used for viewfinders applied to video cameras.

(A) is a plan cross-sectional view when a black and white CRT side image is selected by switching the reflecting mirror in the embodiment of the viewfinder for monochrome and color display according to the present invention, and (b) is a color by switching the reflecting mirror. It is a plane sectional view at the time of selecting a picture on the display panel side. FIG. 4 is a block diagram showing a video switching system in the embodiment of the viewfinder for both monochrome and color display according to the present invention.

Explanation of symbols

10 Viewfinder case body 11 Black and white CRT
12 Color display panel 13 Rotating shaft 14 Reflector 20 Viewfinder unit 21 AWB execution status signal 22 CPU
23 Servo Motor Drive Circuit 24 Reflector Switch 25 Servo Motor 29 Switching Detection Circuit 30 Eyepiece 40 Optical Axis 100 Viewfinder

Claims (3)

A viewfinder combined with a monochrome display and a color display including a monochrome CRT for displaying an image captured by a video camera and a color display panel for displaying the image in color in a viewfinder case body,
The monochrome CRT is disposed at a position off the optical axis to the eyepiece, the color display panel is disposed on the optical axis to the eyepiece, and one end is pivotally supported in the viewfinder case body. When a reflective mirror that can be rotated by a driving unit is arranged and an image to be displayed on the black and white CRT is selected, the image is reflected by the reflective mirror to be supplied to the eyepiece, and the color display is performed. When selecting an image to be displayed on the panel, the image is directly supplied to the eyepiece by rotating the reflector to a position that does not block the optical axis to the eyepiece. A viewfinder for both monochrome and color display. When the auto white balance adjustment function is executed by the driving means, the reflecting mirror is automatically driven to a position for selecting an image displayed on the color display panel, and a predetermined time elapses when the auto white balance adjustment function is completed. 2. The viewfinder for both monochrome and color display according to claim 1, wherein the viewfinder is configured to automatically return to a position for selecting an image displayed later by the monochrome CRT. The power supply to the monochrome CRT and the color display panel is controlled by a detection signal from a switching detection circuit that detects the switching operation of the reflecting mirror, and no display image is selected from the monochrome CRT or the color display panel. 3. The viewfinder for both monochrome and color display according to claim 1, wherein the power supply on the side is automatically turned off.

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