Image sensing apparatus

• US 4,780,764 A
• Filed: 01/29/1987
• Issued: 10/25/1988
• Est. Priority Date: 02/01/1984
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kinoshita, Takao, Suga, Akira, Sakai, Shinji, Tojo, Akihiko
• Primary Examiner(s): Ng, Jin F.
• Assistant Examiner(s): BRINICH, STEPHEN M
• Application Number:
  US07/008,380
• Time in Patent Office: 635 Days
• Field of Search: 358/213.19, 358/213.26, 358/213.31, 358/221, 358/909, 357/24 LR
• US Class Current: 348/296
• CPC Class Codes: H01L 27/14831 Area CCD imagers
• CPC Class Codes: H04N 25/617 for reducing electromagnetic interference, e.g. clocking noise

Abstract

An image sensing apparatus comprises: a photodetector for converting an optical image to a charge signal; a recombination circuit for recombining a portion of the charges in the photodetector with the majority carrier; an instruction circuit for instructing change-over between the still mode, in which only one predetermined image signal is formed in the photodetector, and the movie mode, in which a plurality of image signals are formed; and a controller for switching the recombining capability by the recombination circuit during the formation of an image in accordance with an instruction output of the instruction circuit, in which the recombining capability in the still mode is controlled so as to be higher than that in the movie mode.

Claims

1. An image sensing apparatus comprising:

image sensing means having a plurality of photoelectric conversion cells, each of said cells having first and second regions for converting an optical image to electrical charges;

clearing means for allowing at least a part of the charges in said image sensing means to be cleared;

control means for allowing the charges to be stored in respective ones of said first and second regions for a predetermined interval, and for making said clearing means operative for almost the whole of a blanking period, for a first additional period immediately before said blanking period, and for a second additional blanking period which is shorter than said first additional period, and thereafter adding the charges in said first and second regions and reading them out; and

signal generating means for generating an image signal by processing the electrical charges read out from said image sensing means.

2. An image sensing apparatus according to claim 1, wherein said signal generating means comprises clamp means for periodically clamping the image signal.

3. An image sensing apparatus according to claim 2, wherein said control means does not change the operating state of said clearing means during clamping operation of said clamping means.

4. An image sensing apparatus according to claim 1, further comprising recording means for recording the image signal.

5. An image sensing apparatus according to claim 1, wherein said signal generating means comprises an encoder for generating an NTSC signal at the image signal.

6. An image sensing apparatus comprising:

(a) image sensing means which comprises a photoelectric converting portion for converting an optical image to electrical charges and a signal storing portion for storing the electrical charges after conversion by said photoelectric converting portion;

(b) driving means for peridically transferring the electrical charges from said photoelectric converting portion to said storing portion and thereafter reading the electrical charges out from said storing portion;

(c) recombining means for periodically recombining a portion of charges in said photoelectric converting portion with other charges for almost the whole of the horizontal blanking period and additional periods respectively immediately before and after said horizontal blanking period, wherein said additional period immediately before the horizontal blanking period is longer than said additional period immediately after the blanking period; and

(d) signal generating means for generating an image signal by processing the electrical charges read out from said storing portion.

7. An image sensing apparatus according to claim 6, wherein said signal generating means comprises clamp means for periodically clamping the image signal.

8. An image sensing apparatus according to claim 7, wherein said recombination control means does not change the operating state of said recombining means during clamping operation of said clamping means.

9. An image sensing apparatus according to claim 6, further comprising recording means for recording the image signal.

10. An image sensing apparatus according to claim 6, wherein said signal generating means comprising an encoder for generating an NTSC signal as the image signal.

11. An image sensing apparatus according to claim 6, wherein said image sensing means comprises a frame transfer type CCD.