Image-producing apparatus for a video printer

• US 5,223,960 A
• Filed: 02/22/1991
• Issued: 06/29/1993
• Est. Priority Date: 02/27/1990
• Status: Expired due to Term

• Current Assignee: Goldstar Co., Ltd. (LG Corporation)
• Original Assignee: Goldstar Jewellery LLC
• Inventors: Kim, Jee H.
• Primary Examiner(s): Heyman, John S.
• Assistant Examiner(s): MAI, HUY KIM
• Application Number:
  US07/660,716
• Time in Patent Office: 858 Days
• Field of Search: 350/331 R, 350/333, 350/334, 350/34 E, 350/339 F, 359/42, 359/54, 359/55, 359/59, 359/72, 359/68
• US Class Current: 349/3
• CPC Class Codes: H04N 1/036 for optical reproduction
• CPC Class Codes: H04N 1/50 Picture reproducers for halftone screening H04N1/52

Abstract

An image-producing apparatus for a video printer comprising a liquid crystal display having pixels of red, green, and blue adapted to produce an image in response to a scanning line signal from a video signal, light source disposed at the rear of the liquid crystal display and provided with a screen for producing the image of liquid crystal display on the photosensitive medium. The liquid crystal display comprises a liquid crystal portion including a plurality of liquid crystal elements having the same number and arrangement as those of a line of pixels aligned horizontally, each pixel having vertically-aligned color elements of red, green, and blue to correspond to an image of red, green, and blue colors. The image-producing apparatus of the present invention can reduce volume and the manufacture cost thereof, and provide various image display in order to improve image quality.

Claims

1. An image-exposing apparatus for a video printer comprising:

a liquid crystal display including a liquid crystal portion and a color filter portion where, for each pixel,

said liquid crystal portion has first, second and third liquid crystal pixel elements, said liquid crystal pixel elements having a common scanning line input for turning on the liquid crystal pixel elements, and each of said liquid crystal pixel elements having an independent video input for controlling the transmittivity of the liquid crystal pixel element, and

said color filter portion has red, green and blue filter elements for filtering light from said first, second and third liquid crystal pixel elements, respectively,

light source means disposed at the rear of said liquid crystal display and adapted to transmit light through the liquid crystal pixel elements and the filter elements of the liquid crystal display to form an image having, for each pixel, an intensity of red, green, and blue components proportional to the transmittivity of said first, second and third liquid crystal pixel elements, respectively;

a fiber-optic face plate, disposed at the front of the liquid crystal display and provided with a screen having a photosensitive medium, for transmitting said image of the liquid crystal display onto said photosensitive medium; and

a drum positioned opposite said photosensitive medium for receiving said image from the photosensitive medium.

2. An image-exposing apparatus for a video printer in accordance with claim 1, wherein said screen of the fiber-optics face plate comprises a bundle of fiber optical cables with a small diameter each comprising an inner core adapted to transmit light and a dark cladding coated around said inner core and adapted to prevent light from coming therethrough.

3. An image-exposing apparatus for a video printer in accordance with claim 1, wherein said liquid crystal portion of said display includes first and second liquid crystal portions parts, each part having different transmittivities depending on video signals, said first and second liquid crystal parts aligned for transmitting light from the light source mans to the filer portion of said display, each of said liquid crystal parts having, or each pixel,

first, second and third liquid crystal pixel elements, said liquid crystal pixel elements having a common scanning line input for turning on the liquid crystal pixel elements, and each of said liquid crystal pixel elements having an independent video signal input for controlling the transmittivity of the liquid crystal pixel element.

4. An image-exposing apparatus for a video printer in accordance with claim 3, wherein said scanning line inputs for said liquid crystal pixel elements are each driven with the same common gate pulse.

5. An image-exposing apparatus for a video printer in accordance with claim 1 wherein said light source means includes a fluorescent lamp.

6. An image-exposing apparatus for a video printer comprising:

a liquid crystal display including a liquid crystal portion and a color filter portion,

said liquid crystal portion for forming horizontal rows of pixels where each pixel is defined by vertically-aligned first, second and third liquid crystal pixel elements controlled by first, second and third thin film transistors, respectively, each of said transistors for a liquid crystal pixel element having a gate for receiving a common scanning line input for turning on the transistors for the liquid crystal pixel elements at the same time and each of said transistors for a liquid crystal pixel element having a drain for receiving an independent video input for independently controlling the transmittivity of the liquid crystal pixel element in response to the video input,

said color filter portion has red, green and blue filter elements for filtering light from said first, second and third liquid crystal pixel elements, respectively,

light source means disposed at the rear of said liquid crystal display and adapted to transmit light through the first, second and third liquid crystal pixel elements of the liquid crystal display to form an image having, for each pixel, red, green and blue components with intensities proportional to the transmittivities of said first, second and third liquid crystal pixel elements, respectively; and

a fiber-optic face plate, disposed at the front of the liquid crystal display and provided with a screen having a photosensitive medium, for transmitting said image of the liquid crystal display onto said photosensitive medium.

7. An image-exposing apparatus for a video printer comprising:

a liquid crystal display including a liquid crystal portion and a color filter portion,

said liquid crystal portion for forming horizontal rows of pixels, said liquid crystal portion having two parts, said first and second liquid crystal parts aligned for transmitting light to the filter portion of said display, where each part has independently controlled transmittivity and where for each part, each pixel is defined by vertically-aligned first, second and third liquid crystal pixel elements controlled by first, second, and third thin film transistors, respectively, each of said transistors for a liquid crystal pixel element having a gate for receiving a common scanning line input for turning on the transistors for the liquid crystal pixel element at the same time and each of said transistors for a liquid crystal pixel element having a drain for receiving an independent video input for independently controlling the transmittivity of the liquid crystal pixel element in response to the video input,

said color filter portion has red, green and blue filter elements for filtering light from said first, second and third liquid crystal pixel elements, respectively,

light source means disposed at the rear of said liquid crystal display and adapted to transmit light through the liquid crystal pixel elements of the liquid crystal display to form an image having, for each pixel, red, green and blue components with intensities proportional to the transmittivities of said first, second and third liquid crystal pixel elements, respectively, for each of said parts; and

a fiber-optic face plate, disposed at the front of the liquid crystal display and provided with a screen having a photosensitive medium, for transmitting said image of the liquid crystal display onto said photosensitive medium.