Illuminating and synchronizing device for color imaging equipment

• US 4,713,683 A
• Filed: 08/26/1985
• Issued: 12/15/1987
• Est. Priority Date: 08/31/1984
• Status: Expired due to Term

• Current Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Original Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Inventors: Nagasaki, Tatsuo, Fujimori, Hiroyoshi
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): Bauer, Robert M.
• Application Number:
  US06/768,998
• Time in Patent Office: 841 Days
• Field of Search: 358/42, 358/43, 358/98, 358/44, 128/4-6, 355/35, 362/293
• US Class Current: 348/269
• CPC Class Codes: A61B 1/0638 providing two or more wavelengths
• CPC Class Codes: A61B 1/0646 with illumination filters
• CPC Class Codes: A61B 1/0669 at proximal end of an endoscope
• CPC Class Codes: H04N 23/10 for generating image signals from different wavelengths
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• 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 23/74 by influencing the scene brightness using illuminating means

Abstract

An illuminating device is provided to serve as a lighting source for a subject to be imaged by color imaging equipment and a source of synchronizing signals, and is adjustable to provide light that complements the spectral response characteristics of the solid state image pick-up device used. The device includes a rotating color filter disc interposed between the subject and a source of light, and can be arranged to adjust the amount of light of each of the three primary colors irradiated on the subject by initially selecting the respective areas of each color filter for transmitting each color and/or by sequentially adjusting the intensity of the light source in synchronism with each of the color filter areas passing before it and the synchronizing signals are generated by openings formed in light shielding regions of the disc.

Claims

1. An illuminating and synchronizing system for lighting a subject of an electronic color imaging device which includes a solid state iamge pick-up device, comprising:

an illuminating light source;

color filter means for decomposing light from said light source into different colors comprising a rotating disc having a plurality of color filter areas of different colors separated from one another by light shielding regions and disposed to pass in the light path of said light source between said light source and said subject;

first timing means for producing a color frame detecting signal for each said color filter area to denote the times of passage of said color filter areas in the light path of said light source;

synchronizing signal generating means, responsive to said color frame detecting signals, including three adjustable gain amplifiers and being synchronized by said first timing means to generate a synchronizing signal having a different amplitude corresponding to each of said color filter areas, respectively, and current controlling means connected to said synchronizing signal generating means and to said light source to control the amount of current to said light source, sequentially, in response to said synchronizing signal of different ampitudes and in proportion to amplitudes of the synchronizing signal for sequentially controlling the amount of light passing through said color filter areas in synchronism with the time of passage of respective color filter areas in the light path of said light source;

second timing means for producing a start signal to indicate the beginning of each rotation of said rotating disc;

said first and second timing means comprising openings formed in peripheral areas of said disc light shielding regions, and photo-interrupter means including a plurality of photo-couplers for producing output signals which indicate passage of said openings through said photo-interrupter means; and

signal generator means arranged to receive the output signals of said first and second timing means, and connected to said electronic color imaging device, for generating first reading clock signals to synchronize a driver circuit of said color imaging device to read a signal form said solid state image pick-up device during passage of light shielding regions of said disc between said light source and said subject, and for generating second timing signals to serve as color frame switching signals of said color imaging device.

2. A system as recited in claim 1 wherein said signal generating means comprises a plurality of adjustable gain amplifiers, each responsive to a color frame detecting signal for a respective color filter area arranged to provide a synchronizing signal having a preadjusted amplitude for each color filter area, respectively.

3. An illuminating and synchronizing system as recited in claim 1, wherein said openings formed in said light shielding regions consist of detecting holes corresponding to said color filter areas, a hole being positioned at a different radius of said disc for each color filter area.

4. A system as recited in claim 1, wherein said openings formed in said light shielding regions consist of slits of different radial depths formed in a peripheral area of said disc.

5. A system as recited in claim 4, wherein said color frame detecting signals produced therein each have an amplitude determined by the radial depth of said slits, respectively, and the amount of light passing through each of said color filter areas is controlled in accordance with the amplitude of said color frame detecting signals.