JPH0664237U - Color viewfinder - Google Patents

Abstract

(57) [Summary] [Purpose] Long life due to the use of a liquid crystal shutter.
A color viewfinder capable of converting a monochrome image into a color image at a low cost. A color viewfinder corresponds to a black and white display 3 as a black and white image display means for sequentially scanning each color component representing a color image signal in the horizontal and vertical directions and displaying in black and white. A liquid crystal shutter 41 for inputting a signal indicating the type of color component being displayed and converting the optical signal displayed on the monochrome display 3 into an optical signal having a color component of the image signal, and a liquid crystal shutter 41 for converting the optical signal. A lens section 42 for magnifying and displaying light having different color components, and an optical signal guide section 43 for guiding the optical signal displayed by the monochrome display 3 to the lens section 42 via the liquid crystal shutter 4 by bending the optical path. In the drawing, the liquid crystal shutter 41 is arranged on the front surface on the incident side of the lens section 42, and the optical signal guide section 43 is provided with a reflecting mirror 43a. There.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a color viewfinder, and more particularly to a technique for colorizing a viewfinder of a color television camera through a liquid crystal shutter driven by color-separated color image signals.

[0002]

[Prior art]

 Conventionally, the method of colorizing the viewfinder in a monochrome viewfinder is to rotate a disc on which a red (R), green (G), and blue (B) filter are alternately placed on a monochrome CRT display surface by a motor to rotate the three primary colors. Some display the signals R, G, and B by switching them temporally.

[0003]

[Problems to be solved by the device]

 However, in such a color viewfinder, since the motor mechanically rotates, color misregistration occurs due to inertia or uneven rotation of the motor, or damage occurs due to rotation, resulting in a short mechanical life and cost reduction. However, there was a problem that it was expensive.

Therefore, the present invention has been made in view of the above conventional problems, and by using a liquid crystal shutter driven by sequentially inputting a signal for each color component, a long life and low cost can be achieved. The purpose is to provide a color view finder which is a method for converting a monochrome image into a color image.

[0005]

[Means for Solving the Problems]

 For this reason, the present invention provides a black-and-white image display means for scanning a signal for each color component of a color image horizontally and vertically in a predetermined color order in a color viewfinder mounted on a color television camera. A liquid crystal shutter for inputting a signal representing the type of color component displayed corresponding to this display and converting the optical signal displayed by the monochrome image display means into an optical signal having a color component of the image signal. A lens unit for magnifying and displaying an optical signal having a color component converted by the liquid crystal shutter, and guiding the optical signal displayed by the black and white image display means to the lens unit via the liquid crystal shutter by bending the optical path. And an optical signal guide section.

Further, each field image signal obtained by color-separating a frame color image signal composed of odd and even field images is input, and the field image signals of each color are serially arranged in a predetermined color order between odd fields and even fields. Signal processing means for driving the liquid crystal shutters by the signals distributed by the color components of the output, which are converted into a signal doubled in speed to several times the color components, and output. Outputs to the black-and-white image display means a signal for scanning a specific color component of the signal from the means in the vertical direction by 1/2 of the horizontal scanning interval, and by shifting the odd field and the even field upside down. It is also possible to include a vertical deflection shift means for performing the above.

Further, the liquid crystal shutter can be arranged on the front surface on the incident side of the magnifying display lens portion. Further, the liquid crystal shutter may be arranged on the front surface of the display surface of the monochrome image display means. Further, the optical signal guide unit may be formed of a prism, and the liquid crystal shutter may be arranged on the incident end face or the emission end face of the prism.

[0008]

[Action]

 According to this structure, the color-separated signals of the respective color components (for example, R, G, B) are input to the sequential liquid crystal shutters, and the driving of the respective liquid crystal shutters is switched, so that the monochrome image display means displays the signals. The black-and-white display optical signal is converted into an optical signal having color components and sequentially output. As a result, it can be perceived by human eyes as a color image signal in which these color components are combined.

As described above, the viewfinder can be extremely easily colorized through the liquid crystal shutter driven by the color-separated color image signal. In addition, unlike the conventional method, a disc with a filter is not mechanically rotated by a motor, so that it has a long life and can reduce the product cost.

In addition, the color-separated field signals of the respective color components (for example, R, G, and B) are in a predetermined color order, and odd fields and even fields alternate (R odd → G odd → B odd). → R even → G even → B even) and converted into a signal that has been doubled in color separation several times (for example, 3 times) and input to the monochrome image display means. Then, in the monochrome image display means, a specific color component (for example, G component or R, B component) of the converted image signal is ½ of the scanning interval in the vertical direction and in the odd field. Scanning is performed in the opposite direction between the case and even field, and each image signal for each color component is displayed in the odd field position if it is an odd field, and at the even field position if it is an even field. Interlaced scanning is performed regardless of the field type of the signal, and the original image is displayed as a black-and-white image without distortion, which enables good tracking of moving image movement, high resolution, and flicker. It is possible to obtain stable, high-quality color images.

On the other hand, a switching signal corresponding to the speeded-up serial signal for each color component is input to the liquid crystal shutter, and the liquid crystal shutter has the same color component as the image signal displayed on the monochrome image display means. Each time another signal is input, it is driven to select the corresponding color component. As a result, the colorless optical signal of the monochrome image displayed on the monochrome image display means is converted into an optical signal having a color component corresponding to the image signal. In other words, since the optical image signals for each color component are emitted alternately at high speed, it is recognized by the human eye as a color image in which these color components are combined through the lens unit.

[0012]

Embodiment An embodiment of the present invention will be described below with reference to the drawings. 1 and 2, a color viewfinder according to the present invention includes a black and white display 3 as a black and white image display means for sequentially scanning each color component representing a color image signal in the horizontal and vertical directions to display a black and white image. A liquid crystal shutter 41 that inputs a signal representing the type of color component displayed corresponding to the display of the monochrome display 3 and converts the optical signal displayed on the monochrome display 3 into an optical signal having the color component of the image signal. A lens section 42 for enlarging and displaying the light having the color components converted by the liquid crystal shutter 41, and an optical signal displayed by the monochrome display 3 by bending the optical path to the lens section 42 via the liquid crystal shutter 41. It is composed of an optical signal guide section 43 for guiding.

In the structure shown in FIG. 2, the liquid crystal shutter 41 is arranged on the front surface on the incident side of the lens section 42, and the optical signal guide section 43 is provided with a reflecting mirror 43a. That is, the liquid crystal shutter 41 is sandwiched between the frame 44, the cushion rubber frame 45, and the pressing frame 46, and then fixed to the fixed frame 47 with screws, and the front surface of each fixed frame 47 on the incident side of the lens part 42. It is fixedly supported by a support frame 48 fitted in.

The optical signal emitted from the monochrome display 3 is reflected by the reflecting mirror 43a provided on the eyepiece body 43b and guided to the liquid crystal shutter 41. In addition, 49 shows an eye cup. Next, the system configuration of the color viewfinder according to the present invention will be described with reference to FIG.

In the figure, a vertical synchronizing signal (SYNC) for switching fields of R, G, and B image signals for each color component obtained by color-separating a frame color image signal from a color television camera is a converter as signal processing means. Input to 1. The converter 1 is configured to include a memory that temporarily stores each signal for at least one field, and a signal forming circuit that reads image data from the memory and forms a serial signal. Then, the R, G, and B data stored in the memory are sequentially read in a predetermined color order and at a speed three times the field period, and vertical deflection is performed between R and G, G and B. Is output serially with a period (corresponding to a period of 1/3 of the SYNC) required for the above. That is, R, G, B image data are serially connected, and an RGB serial signal that is three times faster is output.

The RGB serial signals are input to the video control unit 31 of the monochrome display 3 as a monochrome image display unit via the video signal conversion circuit 2. Further, the converter 1 outputs R, G, B selection signals in synchronism with forming and outputting the RGB serial signals, and these signals output the liquid crystal shutter drive signal forming circuit 4 and the V deflection shift signal forming circuit. Input to 5.

Further, the converter 1 speeds up the vertical synchronizing signal SYNC by a factor of 3, and controls reading from the memory based on this signal. This signal is output to the liquid crystal shutter drive signal forming circuit 4, the V deflection shift signal forming circuit 5, and the deflection circuit 6. The liquid crystal shutter drive signal forming circuit 4 selects and transmits the corresponding R, G, B colors in accordance with the input R, G, B selection signals, and outputs the R, G, B signals. In response to the vertical synchronization signal SYNC input during this period, a drive signal for the liquid crystal shutter is formed so that light is not transmitted during this period, and the drive signal is transmitted to the liquid crystal shutter 41 arranged on the front surface on the incident side of the lens section 42. Output.

The V-deflection shift signal forming circuit 5 shifts the scanning of a specific color component, for example, the G component of the R, G, B signals in the vertical direction by ½ of the horizontal scanning line interval. Selects the direction in the even-odd field detected by 3 × SYNC, forms an upward shift in the case of an odd field and a downward shift in the case of an even field, and outputs the V deflection shift signal (interlace shift signal). ) Is output to the vertical deflection circuit 6.

The vertical deflection circuit 6 performs a deflection scan in which it is moved vertically to the scan start position every time the above-described high-speed vertical synchronization signal is input, but the R and B image signals are input. In contrast to the odd-numbered field and the even-numbered field, the deflection is made to the same reference position, whereas the G image signal is shifted downward by 1/2 from the reference position in the horizontal scanning interval in the case of the odd-numbered field as described above. The vertical deflection control signal for deflecting to the position, and in the case of an even field, deflects to a position that is shifted upward by ½ of the horizontal scanning interval from the reference position, and also in the horizontal direction in the field image signal of each color component. A horizontal deflection control signal for deflecting to the horizontal scanning start position each time the synchronizing signal H / SYNC is input is output to the deflection yoke 34 of the monochrome display 3. It

The V deflection shift signal forming circuit 5 and the vertical deflection circuit 6 constitute a vertical deflection shift means. With the above signal processing, the RGB video signal, the vertical deflection control signal V, and the horizontal deflection control signal H are used to sequentially scan each field image of R, G, and B three times as much as the standard television image scan of the input image. When scanning at a speed and switching to a G component field image, vertical deflection is performed while alternately shifting the odd field and the even field in the opposite direction in the vertical direction by 1/2 horizontal scanning interval.

FIG. 4 shows an example of a circuit for shifting the vertical deflection. In the figure, when the V deflection shift signal is input, the transistor T _R1 and the transistor T _R2 are selectively selected depending on whether a vertical upward shift pulse or a downward shift pulse is input. Since it is turned on, the terminal voltage V ₁ of the vertical deflection coil VL is increased / decreased within a predetermined width, whereby the voltage applied to the vertical centering section VC is increased / decreased, so that the vertical scanning for the 1/2 horizontal scanning interval is performed. There are upshifts and downshifts.

FIG. 5 shows an example of another vertical deflection shift circuit. That is, a potential higher than the terminal voltage V ₁ of the vertical deflection coil VL by a predetermined value and a potential lower than the terminal voltage V ₁ by a predetermined value are taken out from the voltage dividing circuit V _V to obtain two fixed contacts a and b of the pulse interlocking IC switch circuit S _1. And the movable contact side of the pulse interlocking IC switch circuit S ₁ is connected to the terminal of the vertical deflection coil VL. A V-deflection shift signal is input to the pulse interlocking IC switch circuit S ₁ , and a contact a is connected when a vertical upward shift pulse is input, and a contact b is connected when a vertical downward shift pulse is input. As a result, the same shift as described above is performed.

Further, in the present embodiment, by shifting only the G component (the component in the middle of the color order) in the vertical direction, the synchronization signal for deflection is an interlace system in which odd fields and even fields are alternately repeated. did. The number of pulses of vertical shift is doubled for the same purpose, but it goes without saying that the same function can be obtained by shifting the R and B components (components at both ends of the color order).

FIG. 6 shows each signal state in such scanning and the scanning state of the screen. That is, the field image of the G component input in the odd field is vertically downwardly shifted by 1/2 horizontal scanning interval and deflected, so that it is substantially converted into the even field image and is also input in the even field. The converted G component field image is vertically shifted by 1/2 horizontal scanning interval and deflected to be converted into an odd field image. Therefore, an interlace method is used in which the odd field and the even field are alternately switched. However, as a result, the scanning according to the field of the input signal is performed on the display screen.

A black-and-white image is displayed on the CRT 32 screen of the black-and-white display 3 on which such scanning is performed. When a colorless light image signal of the black-and-white image is transmitted through the liquid crystal shutter 41 via the optical signal guide section 43, the above-mentioned Since the liquid crystal shutter 41 sequentially transmits as an optical image signal having the corresponding R, G, B color components in synchronization with the scanning period of each R, G, B image signal, these color components are visually combined. The color image is recognized through the lens unit 42.

As described above, the viewfinder can be extremely easily colorized through the liquid crystal shutter 41 driven by the color-separated color image signal. In addition, unlike the conventional method, a disc with a filter is not mechanically rotated by a motor, so that it has a long life and can reduce the product cost.

In particular, in the present embodiment, since the R, G, B image signals are scanned at a speed three times higher than the original signal, the motion of the moving image can be satisfactorily followed and the even field image signal is interpolated. Since it does not generate an odd field screen signal, the color display is not a normal CRT tube consisting of dot trio, but a B / W CRT independent of dot trio, so a high resolution image can be obtained. .

Next, the liquid crystal shutter 41 using a TN mode liquid crystal element will be described with reference to FIGS. 7 and 8. The TN mode liquid crystal device has a basic structure in which liquid crystal molecules are distributed by twisting the direction with respect to the incident light axis direction to the liquid crystal device, and the incident surface and the emission surface are transparent electrodes. It has a sandwiched structure, and the outside is sandwiched by color polarizers.

The operation of the TN mode liquid crystal element will be briefly described with reference to FIG. In this case, the polarizers on the entrance side and the exit side are mounted so that the polarization directions thereof are orthogonal to each other. Now, in the OFF state where no voltage is applied between the electrodes, when the light of the above-mentioned component enters through the polarizer on the incident side, the light is changed in polarization direction by 90 ° by the twist of the liquid crystal molecules, and the light on the emitting side is changed. Since it matches the polarization direction of the polarizer, it is transmitted as it is. Further, in the ON state in which a voltage is applied between the electrodes, the twist of the liquid crystal molecules is returned, so that the light travels in the polarization direction at the time of incidence and is shielded because it is orthogonal to the polarization direction of the exit side polarizer.

Two TN-mode liquid crystal elements having such a principle are used to form a liquid crystal shutter having the above function. That is, as shown in FIG. 8, a BG dichroic polarizing filter 201 for transmitting blue light and green light in the vertical direction and an R dichroic polarizing filter for transmitting red light in the horizontal direction in order from the incident side (left side in the drawing). 20 2, TN mode liquid crystal element 203, B dichroic polarization filter 204 that transmits blue light in the horizontal direction, RG dichroic polarization filter 205 that transmits red light and green light in the vertical direction, TN mode liquid crystal element 206, an RGB dichroic polarization filter 207 that transmits red light, green light, and blue light in the horizontal direction, and controls the two TN-mode liquid crystal elements 203 and 206 by a cell drive unit 208 to turn them on and off. Similar to the example, the three primary color lights are sequentially generated through the light blocking period.

At the top of the figure, the two TN mode liquid crystal elements 203 and 206 are both turned off. In this case, the white light passes through the BG dichroic polarization filter 201 and the blue light and the green light are vertically polarized and transmitted, and the red light passes through the red R dichroic polarization filter 202 and the red light is horizontally polarized and transmitted. To do. Next, when passing through the liquid crystal element 203 in the OFF state, the polarization direction of the light of each color is converted by 90 °, and the red light is deflected in the vertical direction, and the blue light and the green light are deflected in the horizontal direction. Next, while passing through the B dichroic polarizing filter 204 and the RG dichroic polarizing filter 205, the red light and the blue light have the same polarization direction as the respective polarizing filters, but are transmitted as they are, but the green light has the polarization directions orthogonal to each other. Therefore, it is shielded from light. Next, the liquid crystal element 206 in the OFF state converts the polarization direction of the red light in the horizontal direction and the polarization direction of the blue light in the horizontal direction, and transmits the polarized light. After passing through the last RGB dichroic polarization filter 207, red light is transmitted as it is, but blue light is shielded because the polarization directions are orthogonal to each other. In this way, only red light is output.

Similarly, when the liquid crystal element 203 is turned off and the liquid crystal element 206 is turned on as shown in the center of the figure, only blue light is output as shown in the figure, and as shown at the bottom of the figure, the liquid crystal is displayed. When the element 203 is turned on and the liquid crystal element 206 is turned off, only green light is output. Further, although not shown, by controlling both the liquid crystal elements 203 and 206 to be ON, light of all colors is blocked. Therefore, these color polarizers and TN-mode liquid crystal elements are arranged in place of the guest-mode liquid crystal elements and optical shutters, and the cell drive unit 208 performs the above-mentioned four types of switching control, so that Similar to the embodiment, red light, green light, and blue light can be sequentially and repeatedly generated through the light blocking period.

Therefore, the liquid crystal shutter having such a function is arranged in front of the screen of the monochrome display, and the R, G, B signals are sequentially output to the monochrome display and the liquid crystal shutter, and the image signal of each color component is output to the monochrome display. The black-and-white display at the same time is made to pass through the liquid crystal shutter at the same time as the black-and-white display optical image signal, so that the light amount of the light amount corresponding to the image signal is alternately transmitted for each of R, G, and B. Can be recognized as a color image in which optical images for each color component are combined.

Next, another embodiment of the present invention will be described with reference to FIGS. 9 to 11. In FIG. 9, the liquid crystal shutter 41 is arranged on the exit side surface of the monochrome display 3, and other configurations are the same as those shown in FIG. That is, the liquid crystal shutter 41 is sandwiched between the fixed frame 47 and the cushion rubber frame 45 and the pressing frame 46, and then fixed by screws, and each fixed frame 47 is fixedly supported by the light emitting diode display plate 48.

The optical signal emitted from the black and white display 3 is guided to the liquid crystal shutter 41 and then reflected by the optical signal guide section 43. Next, in the structure shown in FIGS. 10 and 11, the optical signal guide section 43 is constituted by the eye piece body 43b and the prism 43c, and the liquid crystal shutter 41 is arranged on the incident side surface or the emitting side of the prism 43c. The other configuration is the same as that shown in FIG.

That is, the liquid crystal shutter 41 is adhered to the incident side surface or the emitting side surface of the prism 43c with an adhesive or the like, and after guiding the optical signal emitted from the monochrome display 3 to the liquid crystal shutter 41, After being bent by the prism 43c or bent by the prism 43c, it is guided to the liquid crystal shutter 41. In the above embodiments, a liquid crystal shutter using a TN mode liquid crystal element is used, but the liquid crystal itself is colored so that the absorption coefficient of the liquid crystal is different from each other in the directions parallel and perpendicular to the long axis of the molecule. A liquid crystal shutter using a guest-host mode liquid crystal element that can switch the transmitted light between colored light and colorless light by turning on and off the voltage by utilizing the chromaticity may be used.

[0037]

[Effect of device]

 As described above, according to the present invention, the viewfinder can be extremely easily colorized through the liquid crystal shutter driven by the color-separated color image signal. In addition, unlike the conventional method, a disc with a filter is not mechanically rotated by a motor, so that it has a long life and can reduce the product cost.

Further, since the field image signal for each color component is interlaced at a high speed in a predetermined color order, the motion of the moving image can be satisfactorily followed, high resolution can be obtained, and flicker or the like can be generated. It is possible to obtain stable, high-quality color images.

[Brief description of drawings]

FIG. 1 is a perspective view showing an external configuration of an eyepiece portion of a color viewfinder according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of FIG.

FIG. 3 is a block circuit diagram showing the configuration of an embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of an example of the vertical deflection shift circuit of FIG.

FIG. 5 is a diagram showing the configuration of another example of the vertical deflection shift circuit of the above.

FIG. 6 is a time chart showing the scanning state and various signals of the above-mentioned embodiment.

FIG. 7 is an explanatory diagram for explaining the operating principle of the TN liquid crystal element.

FIG. 8 is an explanatory diagram for explaining an operating principle of a liquid crystal shutter using a TN liquid crystal element.

FIG. 9 is an exploded perspective view showing another embodiment of the present invention.

FIG. 10 is an exploded perspective view showing another embodiment of the present invention.

FIG. 11 is an exploded perspective view showing another embodiment of the present invention.

[Explanation of symbols]

 1 Converter 3 Monochrome Display 4 Liquid Crystal Shutter Drive Signal Forming Circuit 5 V Deflection Shift Signal Forming Circuit 6 Deflection Circuit 41 Liquid Crystal Shutter 42 Lens 43 Optical Signal Guide 43a Reflector 43b Eyepiece Body 43c Prism 44 Frame 45 Cushion Rubber Frame 46 Holding frame 47 Fixed frame 48 Support frame

Claims (5)

[Scope of utility model registration request] 1. A black-and-white image display means for scanning a signal for each color component of a color image horizontally and vertically in a predetermined color order in a color viewfinder mounted on a color television camera, and this display. A liquid crystal shutter for inputting a signal indicating the type of color component displayed corresponding to the above, and converting the optical signal displayed by the black and white image display means into an optical signal having a color component of the image signal; A lens section for enlarging and displaying an optical signal having a color component converted by the optical signal guide section for guiding the optical signal displayed by the monochrome image display means to the lens section via the liquid crystal shutter by bending the optical path. The color viewfinder is characterized by including and. 2. A field color image signal obtained by color-separating a frame color image signal composed of an odd number field image and an even number field image is input, and the field image signal of each color is serially arranged in a predetermined color order between odd number fields and even number fields. And a signal processing means for converting the signal into a signal that is doubled in speed to several times the speed of the color component and outputting the signal, and driving the liquid crystal shutter by the signal distributed according to the color component of the output, and the signal processing means. A specific color component of the signal from the vertical direction for outputting to the black and white image display means a signal for scanning in the vertical direction by 1/2 of the horizontal scanning interval and shifting upside down in the odd field and the even field. The color viewfinder according to claim 1, further comprising: a deflection shift means. 3. The liquid crystal shutter is arranged on the front surface on the incident side of the magnifying display lens portion.
Alternatively, the color viewfinder described in 2. 4. The color viewfinder according to claim 1, wherein the liquid crystal shutter is provided in front of the display surface of the monochrome image display means. 5. The color viewfinder according to claim 1, wherein the optical signal guide portion is formed of a prism, and the liquid crystal shutter is arranged on an incident end face or an emission end face of the prism.