Sequential color television camera having image intensifier portion

• US 5,103,301 A
• Filed: 10/30/1989
• Issued: 04/07/1992
• Est. Priority Date: 03/25/1988
• Status: Expired due to Fees

• Current Assignee: Alfonso Cosentino
• Original Assignee: Alfonso Cosentino
• Inventors: Cosentino, Alfonso
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): Powell, Mark R.
• Application Number:
  US07/429,965
• Time in Patent Office: 890 Days
• Field of Search: 358/42, 358/211
• US Class Current: 348/217.1
• CPC Class Codes: H04N 23/10 for generating image signals from different wavelengths
• CPC Class Codes: H04N 23/12 with one sensor only

Abstract

A high resolution color television camera system (10) for use to capture high resolution, high quality color video images under reduced lighting conditions, and without supplementary lighting is disclosed. The instant invention can operate at night using only the available light from street lamps, store signs and windows, or even the moon and stars. The output signal is fully compatible with conventional color video transmission equipment. The inventive camera system uses image intensifier camera tubes..sup.(16) High quality imaging and registration of imager is achieved by generating and processing color information using a plurality of formats while achieving optimum results at the various points in the signal generation and transmission system.

Claims

1. A color video system, comprising:

(a) a lens for forming a real optical image;

(b) a photosensitive surface positioned and dimensioned to receive said real optical image and to generate from said real optical image a photoelectron image comprising a plurality of photoelectrons;

(c) a color filter for sequentially passing differently colored components of said real optical image;

(d) a target positioned in facing spaced relationship to said photosensitive surface;

(e) a photoelectron image accelerator for advancing said photoelectrons of said photoelectron image on said photosensitive surface toward said target to form an intensified electron image on said target;

(f) a single electron beam scanner synchronized to said color filter for directly advancing a beam of electrons toward points of said intensified electron image on said target to convert said intensified electron image to a sequential color picture signal sequentially carrying different color components, the direction of said electron beam being varied with time to define a scanning pattern synchronized to said sequential passing of said color filter to generate said sequential color picture signal; and

(g) a converter for converting said sequential color picture signal to simultaneous color picture signals.

2. A system as in claim 1, wherein said converter comprises:

(h) a switch circuit for receiving said sequential color picture signal;

(i) storage means for storing said sequential color picture signal in the form of fields of first, second, and third colors and for outputing simultaneous fields in said colors; and

(j) a control circuit controlling said switch circuit to store said fields in said storage means in response to timing information contained in the output of said scanning means and controlling said storage means to output said simultaneous color picture signals.

3. A system as in claim 2, wherein each of said odd fields of the field sequential signal produced by said scanning means is written into its respective first memory during a respective first interval having a first duration each of said first intervals being separated by a blanking interval;

said first, second, and third color odd color fields being read from said first memory and written into its respective buffer memory during a second interval beginning after three odd color fields, one for each of said colors, are stored, said second interval occurring during the blanking interval in an output simultaneous color signal at the system output said odd color fields stored in said buffer memories being simultaneously read from said buffer memories during a third interval, said third interval being longer than said first and second intervals, in response to control signals produced by said control circuit means, each of said even fields of the field sequential signal produced by said scanning means is written into its respective first memory during a respective fourth interval having a fourth duration each of said fourth intervals being separated by a blanking interval;

said first, second, and third color even color fields being read from said first memory and written into its respective buffer memory during a fifth interval beginning after three even color fields, one for each of said colors, are stored, said fifth interval occurring during the blanking interval in an output simultaneous color signal at the system output, said even color fields stored in said buffer memories being simultaneously read from said buffer memories during a sixth interval, said sixth interval being longer than said fourth and fifth intervals, in response to control signals produced by said control circuit means.

4. A system as in claim 1, wherein said photoelectron image accelerator comprises a multi-stage cascade image intensifier.

5. A system as in claim 1, wherein said color filter is a rotating color filter wheel with red, blue and green segments, said color filter wheel being positioned between said lens and said photosensitive surface.

6. A system as in claim 1, wherein said color filter is a wheel with at least one color filter segment and an open segment which passes white light.

7. A system as in claim 1, wherein said color filter is a liquid crystal device whose color characteristics can be switched electrically.

11. A color video system as in claim 1, wherein said color filter is a color filter wheel with color filter segments of different color characteristics, the movement of respective color filter segments being synchronized to the movement of said electron beam with one of said filter segments positioned to filter during one time period light corresponding to a locus of points of said target whose intensity is being converted by said electron beam, and another of said filter segments being positioned to filter light corresponding to said locus of points during another time period.

8. A low light level color video system, comprising:

(a) optical means for forming an optical image;

(b) a photosensitive surface positioned and dimensioned to receive said optical image and to generate an electron image from said optical image;

(c) color selecting means disposed between said optical means and said photosensitive surface;

(d) target means in facing spaced relationship to said photosensitive surface;

(e) electron image accelerating means for advancing the electron image on said photosensitive surface toward said target means to generate an intensified electron image;

(f) scanning means for scanning said intensified electron image on said target means and for converting it to a color sequential electrical signal;

(g) switch means for receiving said color sequential electrical signal;

(h) storage means for storing said color sequential electrical signal in the form of fields of first, second, and third colors and for outputting simultaneous fields in said colors at respective outputs; and

(i) control circuit means for controlling said switch means and said storage means in response to timing information contained in said color sequential electrical signal to send simultaneous color signals to said outputs.

9. A system as in claim 8, wherein said switch means comprises (i) an analog-to-digital converter and further comprising a digital-to-analog converter associated with each of the outputs for each of said three colors.

12. A color video system as in claim 8, wherein said color filter has effective color characteristics which are different at different times, changes in said effective characteristics being synchronized to the movement of said electron beam with one of said filter segments filtering during one time period, light corresponding to a locus of points of said target whose intensity is being converted by said electron beam, and filtering light corresponding to said locus of points differently during another time period.

10. A color video system, comprising:

(a) a lens for forming a real optical image;

(b) a photosensitive surface positioned and dimensioned to receive said real optical image and generating from said real optical image a photoelectron image comprising a plurality of photoelectrons;

(c) a color filter for sequentially passing differently color components of said real optical image;

(d) a target positioned in facing spaced relationship to said photosensitive surface;

(e) a photoelectron image accelerator for advancing said photoelectrons of said photoelectron image on said photosensitive surface toward said target to form an intensified electron image on said target;

(f) a single electron beam scanner synchronized to said color filter for directly advancing a beam of electrons toward points of said intensified electron image on said target to convert said intensified electron image to a sequential color picture signal sequentially carrying different color components, the direction of said electron beam being varied with time to define a scanning pattern synchronized to said sequential passing of said color filter to generate said sequential color picture signal, wherein each full frame of said scanning pattern has in excess of 1000 lines of image; and

(g) a converter for converting said sequential color picture signal to simultaneous color picture signals.