Strobe apparatus of a still video camera with adjustable color temperature

• US 5,815,204 A
• Filed: 04/08/1997
• Issued: 09/29/1998
• Est. Priority Date: 10/04/1993
• Status: Expired due to Fees

• Current Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
• Original Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
• Inventors: Abe, Tetsuya, Ogawa, Kimiaki
• Primary Examiner(s): Kostak, Victor R.
• Application Number:
  US08/827,709
• Time in Patent Office: 539 Days
• Field of Search: 348/223, 348/224, 348/226, 348/227, 348/228, 348/371, 348/20.71, 348/230, 348/655, 354/430, 354/413, 354/145.1, 354/127.1, 354/126, 396/89, 396/98, 396/158
• US Class Current: 348/371
• CPC Class Codes: G03B 15/05 Combinations of cameras with electronic flash apparatus; Electronic flash units
• CPC Class Codes: G03B 2215/0592 installed in front of light emitter
• CPC Class Codes: H04N 23/56 provided with illuminating means
• CPC Class Codes: H04N 23/74 by influencing the scene brightness using illuminating means
• CPC Class Codes: H04N 23/88 for colour balance, e.g. white-balance circuits or colour temperature control

Abstract

A strobe apparatus includes a light emitter which emits strobe light toward an object to be photographed, and a color temperature detector which detects a color temperature of ambient light reflected by the object. A controller varies a color temperature of the strobe light in accordance with the color temperature of the reflected ambient light. Thus, the color temperature of the object is made substantially identical to a predetermined value corresponding to a specific spectral sensitivity of an image pickup device.

Claims

1. A strobe apparatus of a still video camera having an image pickup device comprising:

light emitting means for emitting strobe light toward an object to be photographed;

color temperature metering means for metering a color temperature of the ambient light reflected from said object;

emitting control means for varying a color temperature of said strobe light in accordance with said color temperature of the ambient light, so that said color temperature of said object is substantially identical to a predetermined value corresponding to a specific spectral sensitivity of said image pickup device;

said light emitting means comprising first and second light emitting tubes which emit different color temperatures of strobe light; and

monochrome liquid crystal filters provided in front of said first and second light emitting tubes to control a quantity of light transmitted by said first and second light emitting tubes.

2. A strobe apparatus according to claim 1, said first and second light emitting tubes having, on the peripheral surfaces thereof, different colored filters.

3. The strobe apparatus of a still video camera according to claim 1, wherein said emitting control means comprises optical means for controlling the color temperature of said strobe light.

4. A strobe apparatus according to claim 1, said emitting control means controlling a density of said monochrome liquid crystal filters.

5. A strobe apparatus according to claim 4, further comprising memory means for storing a data table which represents a correlation between the signal inputted from a color sensor and color temperature of said ambient light.

6. A strobe apparatus according to claim 5, said emitting control means controlling said density of said monochrome liquid crystal filters according to said input signals from said color sensor, using said data table stored in said memory means.

7. A strobe apparatus according to claim 4, said first and said second light emitting means commence emitting light at a same time.

8. A strobe apparatus according to claim 4, said first and second light emitting means emit light for a same duration.

9. A still video camera with a strobe apparatus having a color image pickup device for converting an object image to electrical signals including three color signals comprising:

recording means for recording said electrical signals, said recording means having emitting means for emitting strobe light toward an object to be photographed;

color temperature metering means for metering a color temperature of the ambient light reflected from said object;

optical means for performing white balance adjustment for varying a color temperature of said strobe light in accordance with said color temperature of the ambient light, to achieve a white balance of two color signals of said three color signals output from said color image pickup device;

said emitting means comprising first and second light emitting tubes which emit different color temperatures of strobe light; and

monochrome liquid crystal filters provided in front of said first and second emitting tubes to control a quantity of light transmitted by said first and second light emitting tubes.

10. A still video camera according to claim 9, wherein said first and second light emitting tubes having, on the peripheral surfaces thereof, different colored filters.

11. A still video camera according to claim 10, said optical means controlling a density of said monochrome liquid crystal filters.

12. A still video camera according to claim 11, further comprising memory means for storing a data table which represents a correlation between the signal inputted from a color sensor and color temperature said ambient light.

13. A still video camera according to claim 12, said emitting control means controlling said density of said monochrome liquid crystal filters according to said input signals from said color sensor, using said data table stored in said memory means.

14. A still video camera according to claim 11, said first and said second light emitting tubes commence emitting light at a same time.

15. A still video camera according to claim 11, said first and said second light emitting tubes emitting light for a same duration.

16. A strobe apparatus of a still video camera having an image pickup device comprising:

first and second light emitting tubes for emitting different color temperatures of strobe light toward an object to be photographed;

a color temperature measuring device for measuring a color temperature of ambient light reflected by said object;

emitting control means for varying a color temperature of said strobe light in accordance with said color temperature of the ambient light, so that said color temperature of said object is substantially identical to a predetermined value corresponding to a specific spectral sensitivity of said image pickup device; and

first and second color filters each of a different color on peripheral surfaces of said first and second light emitting tubes, respectively.

17. The strobe apparatus of claim 16, wherein said emitting control means controls a density of said first and second monochrome liquid crystal filters.

18. The strobe apparatus of claim 17, further comprising a memory which stores a data table, wherein data in said data table represents a correlation between a signal from a color temperature measuring device and color temperature of said ambient light.

19. The strobe apparatus of claim 18, wherein said emitting control means controls said density of said monochrome liquid crystal filters according to said signal from said color temperature measuring device and said data.

20. A strobe apparatus of a still video camera having an image pickup device comprising:

first and second light emitting tubes for emitting different color temperatures of strobe light toward an object to be photographed;

a color temperature measuring device for measuring a color temperature of ambient light reflected by said object;

emitting control means for varying a color temperature of said strobe light in accordance with said color temperature of the ambient light, so that said color temperature of said object is substantially identical to a predetermined value corresponding to a specific spectral sensitivity of said image pickup device; and

first and second monochrome liquid crystal filters, provided in front of said first and second light emitting tubes, respectively, which control a quantity of light transmitted by said first and second light emitting tubes.

21. The strobe apparatus of claim 20, wherein said first and second light emitting tubes commence emitting light at a same time.

22. The strobe apparatus of claim 20, wherein said first and second light emitting tubes emit light for a same duration.

23. The strobe apparatus of claim 20, wherein said emitting control means controls a density of said first and second monochrome liquid crystal filters.

24. The strobe apparatus of claim 23, further comprising a memory which stores a data table, wherein data in said data table represents a correlation between a signal from a color temperature measuring device and color temperature of said ambient light.

25. The strobe apparatus of claim 20, wherein said first and second light emitting tubes commence emitting light at a same time.

26. The strobe apparatus of claim 20, wherein said first and second light emitting tubes emit light for a same duration.

40. The strobe apparatus of claim 24, wherein said emitting control means controls said density of said monochrome liquid crystal filters according to said signal from said color temperature measuring device and said data.

27. A still video camera with a strobe apparatus having a color image pickup device for converting an object image to electrical signals including three color signals, comprising:

recording means for recording said electrical signals, said recording means having emitting means for emitting strobe light toward an object to be photographed;

said emitting means including first and second light emitting tubes for emitting different color temperatures of light;

first and second colored filters, each of a different color, on peripheral surfaces of said first and second light emitting tubes, respectively;

a color temperature measuring device for measuring a color temperature of the ambient light reflected from said object; and

white balance adjusting means for varying a color temperature of said strobe light in accordance with said color temperature of the ambient light, to achieve a white balance of two color signals of said three color signals output from said color image pickup device.

29. The strobe apparatus of claim 27, wherein said emitting means controls a density of said first and second monochrome liquid crystal filters.

30. The strobe apparatus of claim 29, further comprising a memory which stores a data table, wherein data in said data table represents a correlation between a signal from said color temperature measuring device and color temperature of said ambient light.

31. The strobe apparatus of claim 29, wherein said emitting control means controls said density of said monochrome liquid crystal filters according to said signal from said color temperature measuring device and said data.

34. The strobe apparatus of claim 27, wherein said emitting means controls a density of said first and second monochrome liquid crystal filters.

35. The strobe apparatus of claim 27, further comprising a memory which stores a data table, wherein data in said data table represents a correlation between a signal from said color temperature measuring device and color temperature of said ambient light.

36. The strobe apparatus of claim 35, wherein said emitting control means controls said density of said monochrome liquid crystal filters according to said signal from said color temperature measuring device and said data.

37. The strobe apparatus of claim 27, wherein said first and second light emitting tubes commence emitting light at a same time.

38. The strobe apparatus of claim 27, wherein said first and second light emitting tubes emit light for a same duration.

39. The strobe apparatus of a still video camera according to claim 31, wherein said emitting control means comprises optical means for controlling the color temperature of said strobe light.

28. A still video camera with a strobe apparatus having a color image pickup device for converting an object image to electrical signals including three color signals, comprising:

recording means for recording said electrical signals, said recording means having emitting means for emitting strobe light toward an object to be photographed;

said emitting means including first and second light emitting tubes for emitting different color temperatures of light;

a color temperature measuring device for measuring a color temperature of the ambient light reflected from said object;

white balance adjusting means for varying a color temperature of said strobe light in accordance with said color temperature of the ambient light, so that a white balance of two color signals of said three color signals output from said color image pickup device is completed; and

first and second monochrome liquid crystal filters, provided in front of said first and second light emitting tubes to control a quantity of light transmitted by said first and second light emitting tubes.

32. The strobe apparatus of claim 28, wherein said first and second light emitting tubes commence emitting light at a same time.

33. The strobe apparatus of claim 28, wherein said first and second light emitting tubes emit light for a same duration.