COLOR TELEVISION CAMERA GENERATING UNIFORM LAG COLOR COMPONENT SIGNALS

• US 3,586,760 A
• Filed: 09/25/1968
• Issued: 06/22/1971
• Est. Priority Date: 09/26/1967
• Status: Expired due to Term

• Current Assignee: Dillenburger Wolfgang
• Original Assignee: Dillenburger Wolfgang
• Inventors: DILLENBURGER WOLFGANG
• Application Number:
  US04/762,393
• Time in Patent Office: 1,000 Days
• US Class Current: 348/339
• CPC Class Codes: H04N 23/16 Optical arrangements associated therewith, e.g. for beam-splitting or for colour correction

Abstract

The different color responsiveness of the image tubes of a color television camera to different color components is compensated by different lenses projecting color images having different sizes onto the photosensitive layers of the image tubes, respectively.

Claims

1. Color television camera comprising, in combination, an objective;

dichroic means for splitting light coming from said objective into a set of color components and forming a set of color component channels;

a set of image tubes including photosensitive layers having different sensitivity to different color components and producing potential changes and color component signals of different magnitude when impinged by color components of different spectral rangEs having the same intensity; and

a set of optical means located in said color component channels, respectively, for projecting said color components onto said photosensitive layers, respectively, at least one optical means of said set having different optical properties than the other optical means of said set and including lens means for forming on the respective layer a color component image having a different size than the other color component images, and selected for compensating different sensitivities of said layers to different color components so that the photosensitive layers of all image tubes produce potential changes of substantially the same magnitude.

2. Color television camera as claimed in claim 1 wherein said lens means forms in the respective color component channel a color image which is smaller that the color images in the respective other color component channels.

3. Color television camera as claimed in claim 1 wherein said set of optical means includes a set of different lens means having different optical properties for forming on said layers color component images having different sizes, respectively, said sizes being selected for compensating said different sensitivities of said layers to different color components.

4. Color television camera as claimed in claim 3 wherein said dichroic means produce green, blue and red color components;

and wherein said lens means have such different optical properties that the images formed of said blue and red color components by two of said lens means on the photosensitive layers of two of said image tubes are substantially smaller than the image formed of said green color component by a third lens means on the photosensitive layer of a third image tube.

5. Color television camera as claimed in claim 1 wherein said set of optical means includes a set of lens means, said lens means having different focal lengths, and focal points located on said photosensitive layers of said image tubes, respectively, for forming images having different sizes on said photosensitive layers, respectively.

6. Color television camera as claimed in claim 1 wherein said dichroic means produce green, blue and red color components;

wherein said set of optical means includes a set of lens means, said lens means having different focal lengths, and focal points located on said photosensitive layers of said image tubes, respectively, for forming images having different sizes on said photosensitive layers, respectively;

wherein said lens means are located in said color component channels associated with said green, blue and red color components, respectively; and

wherein the focal lengths of the two lens means in the red and blue color component channels are substantially smaller than the focal length of the lens means in the green color component channel.

7. Color television camera as claimed in claim 6 wherein the focal lengths of the two lens means in said red and blue color component channels are about half the focal length of the lens means located in said green color component channel.

8. Color television camera as claimed in claim 6 wherein the focal length of the lens means in said red color component channel is less than the focal length of the lens means in said green color component channel and at least as great as the focal length of the lens means in said blue color component channel.

9. Color television camera as claimed in claim 1 wherein said dichroic means produce blue, red and green color components;

wherein said set of optical means includes a set of lens means located in blue, red and green color component channels, respectively; and

wherein the focal length of the lens means in said red color component channel is less than the focal length of the lens means in said green color component channel and greater then the focal length of the lens means in said blue color component channel.

10. Color television camera as claimed in claim 9 wherein said lens means of said set of lens meanS have relative apertures in a ratio reciprocal to the ratio between said focal lengths so that the amounts of colored light of said three color components projected by said lens means onto said photosensitive layers of said image tubes, respectively, are the same.

11. Color television camera as claimed in claim 1 comprising a semitransparent mirror for dividing white light from said objective into first and second white light components;

a luminescence image tube having a photosensitive layer receiving said first white light component; and

optical means for guiding said second white light component to said dichroic means for splitting into said color components.