Electronic camera with movable optical element

• US 6,583,819 B2
• Filed: 06/18/2001
• Issued: 06/24/2003
• Est. Priority Date: 06/19/2000
• Status: Expired due to Fees

• Current Assignee: Pentax Corporation (Hoya Corporation)
• Original Assignee: Pentax Corporation (Hoya Corporation)
• Inventors: Ito, Takayuki, Noguchi, Masato, Mogamiya, Makoto
• Primary Examiner(s): Garber, Wendy R.
• Assistant Examiner(s): Rosendale, Matthew L
• Application Number:
  US09/881,776
• Publication Number:
  US 20010053288A1
• Time in Patent Office: 736 Days
• Field of Search: 348/342, 348/335, 348/340, 348/360, 348/361, 348/164, 348/218.1, 348/219.1
• US Class Current: 348/335
• CPC Class Codes: H04N 23/52 Elements optimising image sensor operation, e.g. for electromagnetic interference [EMI] protection or temperature control by heat transfer or cooling elements
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/81 for suppressing or minimising disturbance in the image signal generation
• CPC Class Codes: H04N 23/811 by dust removal, e.g. from surfaces of the image sensor or processing of the image signal output by the electronic image sensor

Abstract

An electronic camera (digital camera) includes a taking optical system that forms an image of a subject, a lowpass filter and a CCD area sensor that captures the image formed by the taking optical system. The lowpass filter is mounted on a driving mechanism that moves it in the direction parallel to a light-receptive surface of the CCD. The driving mechanism consists of a pair of filter guides that support the filter, a pair of shafts that guide rectilinear movement of the filter, a cam disc that is rotated by a motor and a cam follower attached on the guide. When the picture is taken, the motor rotates the disk, which reciprocates the filter. Since the movement of the lowpass filter moves the shadow of the dust formed on the CCD area sensor, an influence of the shadow is diffused among a larger number of pixels.

Claims

1. An electronic camera comprising:

a taking optical system that forms a subject image;

an image pickup device that converts an optical image formed thereon into electric signals;

an optical element that is located between said taking optical system and said image pickup device, said optical element allowing the light from the subject to pass therethrough; and

a driving mechanism that reciprocally and linearly moves said optical element in a direction that is substantially parallel to a light-receptive surface of said image pickup device, wherein said driving mechanism moves said optical element while said image pickup converts the optical image into electric signals.

2. The electronic camera according to claim 1, further comprising a shutter located between said taking optical system and said optical element, wherein said driving mechanism moves said optical element while said shutter opens.

3. The electronic camera according to claim 1, wherein said optical element comprises a lowpass filter.

4. The electronic camera according to claim 1, wherein said optical element comprises an infrared absorbing filter.

5. The electronic camera according to claim 1, wherein said image pickup device comprises a CCD area sensor.

6. The electronic camera according to claim 2, wherein said driving mechanism comprises a motor and a cam mechanism that converts rotational movement of said motor into reciprocating rectilinear movement to move said optical element.

7. The electronic camera according to claim 2, wherein said optical element comprises a lowpass filter.

8. The electronic camera according to claim 2, wherein said optical element comprises an infrared absorbing filter.

9. The electronic camera according to claim 2, wherein said image pickup device comprises a CCD area sensor.

10. The electronic camera according to claim 2, wherein said optical element is supported by a pair of guides which are configured to move along a pair of parallel shafts.

11. An electronic camera comprising:

a taking optical system that forms a subject image;

an image pickup device that converts an optical image formed thereon into electric signals;

an optical element that is located between said taking optical system and said image pickup device, said optical element allowing the light from the subject to pass therethrough; and

a driving mechanism that moves said optical element in a direction that is substantially parallel to a light-receptive surface of said image pickup device, said driving mechanism comprising a motor and a cam mechanism that converts rotational movement of said motor into reciprocating rectilinear movement to move said optical element, wherein said driving mechanism moves said optical element while said image pickup converts the optical image into electric signals.

12. The electronic camera according to claim 11, wherein said optical element comprises a lowpass filter.

13. The electronic camera according to claim 11, wherein said optical element comprises an infrared absorbing filter.

14. The electronic camera according to claim 11, wherein said image pickup device comprises a CCD area sensor.

15. The electronic camera according to claim 11, wherein said optical element is supported by a pair of guides which are configured to move along a pair of parallel shafts.

16. An electronic camera comprising:

a taking optical system that forms a subject image;

an image pickup device that converts an optical image formed thereon into electric signals;

an optical element that is located between said taking optical system and said image pickup device, said optical element allowing the light from the subject to pass therethrough, wherein said optical element is supported by a pair of guides which are configured to move along a pair of parallel shafts; and

a driving mechanism that moves said optical element in a direction that is substantially parallel to a light-receptive surface of said image pickup device, wherein said driving mechanism moves said optical element while said image pickup converts the optical image into electric signals.