Color video endoscope system with electronic color filtering

• US 4,742,388 A
• Filed: 05/18/1984
• Issued: 05/03/1988
• Est. Priority Date: 05/18/1984
• Status: Expired due to Term

• Current Assignee: Fuji Photo Optical Co. Ltd (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Optical Co. Ltd (Fujifilm Holdings Corporation)
• Inventors: Hunyady, Janos L., Cooper, David H.
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): Kostak, Victor R.
• Application Number:
  US06/611,617
• Time in Patent Office: 1,446 Days
• Field of Search: 358/98, 358/901, 358/209, 358/1, 358/29, 358/29 C, 128/4-11
• US Class Current: 348/71
• CPC Class Codes: A61B 1/05 characterised by the image sensor, e.g. camera, being in the distal end portion
• CPC Class Codes: H04N 23/125 Colour sequential image capture, e.g. using a colour wheel
• CPC Class Codes: H04N 23/555 for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes
• CPC Class Codes: H04N 23/63 by using electronic viewfinders

Abstract

A color video endoscope system including a light source, color wheel and light guide for directing sequential fields of red, green and blue (RGB) light into a cavity, a solid state image sensor for transmitting a signal in response to the intensity of the reflected fields of light, a video processor for converting the signal from the image sensor into a composite RGB video signal compatible with a color monitor, and a plurality of electronic color filters for altering the true color of the image on the monitor.

Claims

1. A color video endoscope system for use in displaying an image produced by light reflected from objects inside a cavity on a monitor, comprising:

means for generating and delivering sequential color fields of light;

an image sensor having a field of view for sensing light reflected from objects within the cavity and for producing an electrical signal in response to the intensity of light received, the electrical signal having sequential components corresponding to the reflected light;

processing means, electrically coupled to the image sensor for sequentially processing the signal components from the image sensor into a video signal, for presentation of an image on the monitor; and

means electrically coupled to the image sensor signal processing means for altering the signal components in the processing means so as to alter the color of the image on the monitor.

2. The color video endoscope system according to claim 1 wherein the signal component altering means includes means for altering the gain for each of the signal components in the processing means.

3. The color video endoscope system according to claim 1 wherein the signal component altering means includes means for removing all but one of the signal components corresponding to all but one of the color fields so as to create a single-color image on the monitor.

4. In a color video endoscope system of the type having means for generating sequential fields of red, green, and blue light into a cavity, an image sensor for generating a sequential signal in response to the sequential fields of color light reflected from within the cavity, and means electrically coupled to the image sensor for processing the sequential signal into a true color image displayed on a monitor, an improvement for electronically filtering light from the true color image on the monitor comprising means electrically coupled to the processing means for applying a specific gain to each portion of the sequential signal from the image sensor corresponding to a particular color field.

5. The improved color video endoscope system according to claim 4 wherein the gain application means further comprises means for selecting one of a number of combinations of preset gains to be applied to the portions of the sequential signal corresponding to red, green, and blue light.

6. The improved color video endoscope system according to claim 5 wherein the selection means further comprises means for individually varying each of the preset gains.

7. In a color video endoscope system of the type having means for generating sequential fields of red, green, and blue light into a cavity, an image sensor for generating a signal having sequential components corresponding to the light from the color fields reflected from within the cavity, and means electrically coupled to the image sensor for converting the sequential signal components from the image sensor into a video signal for presentation of a color image on a monitor, an improvement to the color video endoscope system comprising:

means for applying one of a plurality of preset voltage levels to the red signal component;

means for applying a fixed image sensor-dependent voltage level to the red signal component;

means for applying one of a plurality of preset voltage levels to the green signal component;

means for applying a fixed image sensor-dependent voltage level to the green signal component;

means for applying one of a plurality of preset voltage levels to the blue signal component;

means for applying a fixed image sensor-dependent voltage level to the blue signal component;

means for summing the preset voltage level and the fixed image sensor-dependent voltage level for each of the red, green and blue signal components;

a plurality of gates, each gate being electrically coupled between the means for summing the voltage levels applied to a corresponding signal component and the signal component conversion means;

timing means electrically coupled to each of the gates for sequentially connecting the summed voltage levels to be applied to each of the signal components to the signal component conversion means in synchronization with the red, green and blue signal components transmitted by the image sensor to the signal component conversion means; and

means electrically coupled to the red, green and blue preset voltage level applications means for selecting one of a plurality of combinations of red, green and blue preset voltage levels, each combination corresponding to a predetermined color filter effect on the monitor.

8. The improved color video endoscope system according to claim 7 further comprising means for adjusting each of the preset voltage levels to be applied to each of the red, green and blue signal components, whereby the color filter effects corresponding to the combinations of red, green and blue preset voltage levels may be changed.

9. A color video endoscope system for use in displaying an image produced by light reflected from objects inside a cavity on a monitor, comprising:

means for generating and delivering sequential color fields of light;

an image sensor having a field of view for sensing light reflected from objects within the cavity and for producing an electrical signal in response to the intensity of light received, the electrical signal having sequential components corresponding to the reflected light;

processing means, electrically coupled to the image sensor for sequentially processing the signal components from the image sensor into a video signal, for presentation of an image on the monitor;

means electrically coupled to the image sensor signal processing means for altering the signal components in the processing means so as to alter the color of the image on the monitor;

means electrically coupled to the processing means for transmitted to the processing means a fixed gain level for each signal component in the processing means, the fixed gain levels being predetermined image sensor-dependent levels to create a true color image on the monitor;

timing means electrically coupled to the processing means and the fixed gain level transmitting means for applying each of the fixed gain levels to the proper signal component corresponding to the proper sequential color field, and;

means electrically coupled to the processing means for summing each of the fixed gain levels with the gain altered for each of the signal components by the signal altering means.