Ring light guide device for camera

• US 6,430,371 B1
• Filed: 03/24/2000
• Issued: 08/06/2002
• Est. Priority Date: 03/24/1999
• Status: Expired due to Fees

• Current Assignee: Sung Hwan Cho
• Original Assignee: Sung Hwan Cho
• Inventors: Cho, Sung Hwan
• Primary Examiner(s): Adams, Russell
• Assistant Examiner(s): Smith, Arthur A
• Application Number:
  US09/534,169
• Time in Patent Office: 865 Days
• Field of Search: 396/16, 396/17, 396/19, 396/71, 396/267, 396/199, 396/176, 396/14, 396/106, 396/189, 396/190
• US Class Current: 396/176
• CPC Class Codes: G03B 15/03 Combinations of cameras with lighting apparatus; Flash units

Abstract

Disclosed is a ring light guide device for a camera. The ring light guide device comprises a housing having an adaptor inserting hole which is formed therethrough at a side thereof in a manner such that the adaptor inserting hole has an axis which is coaxial with a center axis of a lens of the camera, the housing being detachably coupled on a rear surface thereof with a camera fitting adaptor by the fact that the camera fitting adaptor is inserted into the adaptor inserting hole, light receiving section installed opposite to a light source of the camera, for receiving light which is emitted from the light source; light path changing section for changing a path of light received by the light receiving section in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to the center axis of the lens of the camera; and irradiation adjusting section for adjusting an amount of light which is irradiated to the object, depending upon a camera-to-object distance.

Claims

1. A ring light guide device for a camera, comprising:

a housing having an adaptor inserting hole which is formed therethrough at a side thereof in a manner such that the adaptor inserting hole has an axis which is coaxial with a center axis of a lens of the camera, the housing being detachably coupled on a rear surface thereof with a camera fitting adaptor by the fact that the camera fitting adaptor is inserted into the adaptor inserting hole;

light receiving means installed opposite to a light source of the camera, for receiving light which is emitted from the light source;

light path changing means for changing a path of light received by the light receiving means in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to the center axis of the lens of the camera; and

irradiation adjusting assembly constructed to to adjust an amount of light which is irradiated to the object, depending upon a camera-to-object distance, the irradiation adjusting assembly comprising;

a first polarized filter rotatably installed inside the housing in a manner such that the first polarized filter is opposite to the light source of the camera, for allowing only one linear polarized light component of received light to pass therethrough;

a second polarized filter installed downstream of the first polarized filter, the second polarized filter cooperating with the first polarized filter for determining an amount of the one linear polarized light component which can pass through them; and

an adjusting piece fixed around the first polarized filter in a manner such that the adjusting piece partially projects out of the housing.

8. The ring light guide device as claimed in claim 1, wherein the light path changing means comprises a bundle of optical fibers.

9. The ring light guide device as claimed in any one of claims 1, 8 or 3, further comprising:

a magnification lens located forward of the lens of the camera for enlarging an incident image to a preset magnification.

10. The ring light guide device as claimed in claims 1 or 3, further comprising:

distance measuring means for measuring the camera-to-object distance;

brightness measuring means for measuring a brightness of the object;

a driving motor for rotatably driving the first polarized filter or the second polarized filter; and

controlling means for determining, on the basis of the camera-to-object distance and the brightness of the object, an adequate amount of light which is to be irradiated to the object and thereupon for driving the driving motor.

11. The ring light guide device according to claim 10, further comprising:

a magnification lens located forward of the lens of the camera for enlarging an incident image to a preset magnification.

2. A ring light guide device for a camera, comprising:

light receiving means arranged in front of a light source of the camera for receiving light which is emitted from the light source;

light path changing means for changing a path of light received by the light receiving means in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to a center axis of a lens of the camera; and

irradiation adjusting means for adjusting an amount of light which is irradiated to the object, depending upon a camera-to-object distance, wherein the irradiation adjusting means comprises;

first and second polarized filters located over an entire light receiving area of the light receiving means for adjusting, depending upon an angle which is defined between their polarization axes, an amount of light to be received by the light receiving means.

3. A ring light guide device for a camera, comprising:

a housing having an adaptor inserting hole which is formed therethrough at a side thereof in a manner such that the adaptor inserting hole has an axis which is coaxial with a center axis of a lens of the camera, the housing being detachably coupled on a rear surface thereof with a camera fitting adaptor by the fact that the camera fitting adaptor is inserted into the adaptor inserting hole;

light receiving means installed opposite to a light source of the camera, for receiving light which is emitted from the light source;

light path changing means for changing a path of light received by the light receiving means in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to the center axis of the lens of the camera; and

irradiation adjusting assembly constructed to adjust an amount of light which is irradiated to the object, depending upon a camera-to-object distance, the irradiation adjusting assembly comprising;

a first polarized filter located at an output side of the light path adjusting means, for allowing only one linear polarized light component of irradiated light to pass therethrough, the first polarized filter having a ring-shaped configuration; and

a second polarized filter located inside the adaptor inserting hole, for receiving only reflected light which is reflected from the object after being irradiated through the first polarized filter to the object and then for making the reflected light incident to the lens of the camera.

4. A ring light guide device for a camera, comprising:

light receiving means arranged in front of a light source of the camera for receiving light which is emitted from the light source;

light path changing means for changing a path of light received by the light receiving means in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to a center axis of a lens of the camera; and

irradiation adjusting means for adjusting an amount of light which is irradiated to the object, depending upon a camera-to-object distance, wherein the irradiation adjusting means comprises;

first and second polarized filters located at an output side of the light path changing means for adjusting, depending upon an angle which is defined between their polarization axes, an amount of light to be received by the light receiving means, the first and second polarized filters having a ring-shaped configuration.

12. The ring light guide device as claimed in claim 4, wherein the irradiation adjusting means further comprises:

a third polarized filter located in front of the lens of the camera for receiving only reflected light which is reflected from the object after being irradiated through the first and second polarized filters to the object.

13. The ring light guide device as claimed in claim 12, wherein the first and second polarized filters are simultaneously rotated along with and relative to the third polarized filter in a state wherein their polarization axes are aligned on the same straight line.

14. The ring light guide device as claimed in any one of claims 2, 12, 13, or 4-7, wherein the light receiving means and the irradiation adjusting means are coupled to the camera in a state wherein they are separated from each other.

15. The ring light guide device as claimed in claim 14, wherein the light path changing means is covered by a flexible bellows tube.

16. The ring light guide device as claimed in any one of claims 2, 12, 13, or 4-7, further comprising:

a magnification lens located forward of the lens of the camera for enlarging an incident image to a preset magnification.

17. The ring light guide device as claimed in any one of claims 2, 12, 13, or 4-7, further comprising:

a camera fitting adaptor for detachably coupling a guide-path-defining section of a housing for guiding an incident image from the object to the lens of the camera, to a lens connection ring of the camera.

5. A ring light guide device for a camera, comprising:

light receiving means arranged in front of a light source of the camera for receiving light which is emitted from the light source;

light path changing means for changing a path of light received by the light receiving means in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to a center axis of a lens of the camera; and

irradiation adjusting assembly constructed to adjust an amount of light which is irradiated to the object, depending upon a camera-to-object distance, the irradiation adjusting assembly comprising;

a first polarized filter located at an output side of the light path changing means for allowing only one linear polarized light component of light to be irradiated, the first polarized filter having a ring-shaped configuration; and

a second polarized filter located in front of the lens of the camera for receiving only reflected light which is reflected from the object after being irradiated through the first polarized filter to the object.

6. A ring light guide device for a camera, comprising:

light receiving means arranged in front of a light source of the camera for receiving light which is emitted from the light source;

light path changing means for changing a path of light received by the light receiving means in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to a center axis of a lens of the camera; and

irradiation adjusting assembly constructed to adjust an amount of light which is irradiated to the object, depending upon a camera-to-object distance, the irradiation adjusting assembly comprising;

a movable member located in front of the light source of the camera in a manner such that the movable member can be moved in forward and rearward directions, the movable member having light receiving means arranged therein; and

distance altering means threadedly coupled around a circumferential outer surface of the movable member, for altering a distance between the light source of the camera and the light receiving means.

7. A ring light guide device for a camera, comprising:

light receiving means arranged in front of a light source of the camera for receiving light which is emitted from the light source;

light path changing means for changing a path of light received by the light receiving means in a manner such that the light is irradiated toward an object in a direction which is substantially parallel to a center axis of a lens of the camera; and

irradiation adjusting means for adjusting an amount of light which is irradiated to the object, depending upon a camera-to-object distance, wherein the irradiation adjusting means automatically adjusts a light irradiation amount depending upon the camera-to-object distance and a brightness of the object.