Electronic endoscope apparatus capable of driving solid state imaging devices having different characteristics

• US 4,926,258 A
• Filed: 10/11/1988
• Issued: 05/15/1990
• Est. Priority Date: 10/20/1987
• Status: Expired due to Term

• Current Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Original Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Inventors: Hasegawa, Jun, Yamashita, Shinji, Uchikubo, Akinobu, Saito, Katsuyuki, Sasagawa, Katsuyoshi, Sasaki, Masahiko, Uehara, Masao, Kanno, Masahide
• Primary Examiner(s): Peng, John K.
• Application Number:
  US07/255,228
• Time in Patent Office: 581 Days
• Field of Search: 358/98, 358/213.26, 128/4, 128/6
• US Class Current: 348/72
• CPC Class Codes: H04N 23/125 Colour sequential image capture, e.g. using a colour wheel
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/555 for picking-up images in sites, inaccessible due to their dimensions or hazardous conditions, e.g. endoscopes or borescopes

Abstract

An apparatus has a simple configuration using a drive circuit for outputting horizontal transfer clocks with a given frequency regardless of the number of picture elements of a solid state imaging device which constitutes an imaging means of an endoscope and the reading structure thereof so that it can be used for an endoscope having a different number of picture elements.

Claims

1. An endoscope apparatus comprising:

first and second endoscope means having long, thin first and second insertion portions, first and second projection means each projecting illuminating light from one end of each of said insertion portions, first and second objective optical systems respectively provided at said ends of said first and second insertion portions to form an optical image of an object and first and second solid state imaging devices for respectively performing photoelectric conversion of the images based on said first and second objective optical systems, said first and second imaging devices having different numbers of picture elements;

a driving signal generating means for mixing outputs generated to at least one of a signal regardless of said number of said picture elements in said solid state imaging devices, and of another signal in accordance with said number of said picture elements of said imaging devices, and said driving signal generating means further outputting a driving signal containing a horizontal transfer clock signal with a given frequency for each of said first and second solid state imaging devices even if said number of said picture elements of said first and second solid state imaging devices are different to thereby produce said driving signal to each of said solid state imaging devices;

a picture signal processing means for performing signal processing of the signal read from each of said first and second solid state imaging devices using said driving signal applied thereto to produce a given picture signal; and

a monitor means for displaying said given picture signal.

3. An apparatus according to claim 1, wherein at least one of said first and second endoscope means has first and second light projection means, and is an electronic scope in which said first and second solid state imaging devices are respectively disposed at the positions of image formation of said first and second objective optical systems.

4. An apparatus according to claim 1, wherein at least one of said first and second endoscope means has first and second light projection means, and is an endoscope with an outer television camera having a fiberscope including an image guide for transmitting the image based on each of said first and second objective optical systems, and a television camera mounted on said fiberscope and wherein each of said first and second solid state imaging devices is disposed at the position of image formation of the image transmitted by said image guide means.

5. An apparatus according to claim 3 or 4, wherein at least one of said first and second light projection means has a projection end disposed at one end of said first or second insertion portion and is composed of a light guide means for transmitting illuminating light, said illuminating light being supplied to the incidence end of said light guide means from a light source means.

6. An apparatus according to claim 3 or 4, wherein at least one of said first and second light projection means comprises of a lamp disposed at the end of said first or second insertion portion.

7. An apparatus according to claim 5, wherein said light source means employs a surface sequential type of illumination and comprises a lamp, a rotary color filter provided with a plurality of color transmitting filters which respectively transmit light with different wavelength regions, and a motor for rotating said rotary color filter.

8. An apparatus according to claim 3 or 4, wherein said driving signal generating means comprises a horizontal transfer clock generating means for generating said horizontal transfer clock, a gate means for opening or closing a gate for said horizontal transfer clock to output a row of horizontal transfer clocks, a means for changing the number or said horizontal transfer clocks used for selectively changing over the period of opening and closing of said gate, and a vertical transfer generating means for generating a vertical transfer clock at the time said gate is closed.

9. An apparatus according to claim 8, wherein said driving signal generating means has a means for generating a clock for transfer between said horizontal transfer registers subsequently to said vertical transfer clock when said gate is closed.

10. An apparatus according to claim 3 or 4, wherein said first and second light projection means has a means for changing the exposure time of each of said solid state imaging devices in accordance with said number of said picture elements.

11. An apparatus according to claim 3 or 4, wherein said first and second endoscope means respectively have information sources with respect to said numbers of said picture elements of said first and second solid state imaging devices.

12. An apparatus according to claim 11, wherein said driving signal generating means and said picture signal processing means are contained in a signal processing apparatus having a connection portion that enables said first or second endoscope means to be connected thereto and a decoding means for decoding the information of said information source when said first or second endoscope means is connected.

13. An apparatus according to claim 3 or 4, wherein said picture signal processing means does not change the characteristics of the entire processing system for processing picture signals even if said numbers of said picture elements are different.

14. An apparatus according to claim 11, wherein said picture signal processing means has a means for changing characteristics which is capable of changing said characteristics used for picture signal processing in accordance with said numbers of said picture elements.

15. An apparatus according to claim 11, wherein said first and second light projection means has a switching means for switching the exposure time in accordance with said number of said picture elements of said first and second solid state imaging devices.

16. An apparatus according to claim 11, wherein said picture signal processing means has a switching means for switching the characteristics of the picture signal processing system for processing picture signals in accordance with said numbers of said picture elements of said first and second solid state imaging devices.

17. An apparatus according to claim 15, wherein said switching means is capable of manual switching.

18. An apparatus according to claim 15 further comprising a decoding means for decoding said information of said information source so that said switching means performs automatic switching using the switching signal which is output from said decoding means and applied thereto.

19. An apparatus according to claims 1 or 2, wherein said drive signal generating means has a filter which transmits only the basic wave of said horizontal transfer clocks and the harmonic wave thereof.

20. An apparatus according to claim 1 or 2, wherein said picture signal processing means has a first low-pass filter means for cutting off unnecessary harmonics, an A/D converting means for performing A/D conversion of a signal which was passed through said filter means, a digital memory means in which digital signals passed through said A/D converting means are stored, a D/A converting means for performing D/A conversion of the digital signals read from said memory means, and a second low-pass filter means for cutting off the harmonics of the analogue signals output from said D/A converting means.

21. An apparatus according to claim 20 further comprising a means for changing at least one of the clock used for reading from said digital memory means, the D/A conversion rate of said D/A converting means, and the frequency of cutting off by said second low-pass filter means.

22. An apparatus according to claim 21, wherein said picture signal processing means has an outline enhancing means for performing outline enhancement in front of or behind said second low-pass filter means and a means for switching the frequency of said outline enhancement by said outline enhancing means.

23. An apparatus according to claim 6 further comprising a means for changing the amount of light emitted from said lamp.

24. An apparatus according to claim 1 or 2, wherein said driving signal generating means serves to change the clock numbers of said horizontal transfer clock in accordance with said numbers of said picture elements.

25. An apparatus according to claim 1 or 2, wherein said driving signal generating means has a means for generating said horizontal transfer clocks which does not change the clock number of said horizontal transfer clock even if said numbers of said picture elements of said solid state imaging devices are different from each other.

26. An apparatus according to claim 25, wherein said means for generating said horizontal transfer clock outputs a clock row of a clock number greater than the maximum of horizontal picture elements in said first and second imaging devices.

27. An apparatus according to claim 26, wherein said means for generating said horizontal transfer clock signal outputs a clock sequence of a number greater than the maximum number of the vertical picture elements.

28. An apparatus according to claim 1 or 2, wherein said driving signal generating means has a means for generating a vertical transfer clock signal with a given period at the same time as a row of said horizontal transfer clock signal with a given frequency.

29. An apparatus according to claim 1 or 2, wherein said driving signal generating means has a plurality of means for generating said horizontal transfer clocks when said first or second solid state imaging device has a plurality of horizontal transfer registers.

30. An apparatus according to claim 1 or 2, wherein said driving signal generating means has a means for generating a signal for transfer between registers in correspondence with the case in which said first or second solid state imaging device has said plurality of said horizontal transfer registers.

31. An apparatus according to claim 16, wherein said switching means is capable of manual switching.

32. An apparatus according to claim 16 further comprising a decoding means for decoding said information of said information source so that said switching means performs automatic switching using the switching signal which is output from said decoding means and applied thereto.

2. An endoscope signal processing apparatus comprising:

a driving signal generating means in which each of first and second endoscope means respectively using as imaging means first and second solid state imaging devices having different numbers of picture elements can be mounted and which outputs a driving signal containing a horizontal transfer clock with a given frequency to said first and second solid state imaging devices regardless of differences in said numbers of said picture elements; and

a picture signal processing means which performs signal processing of the signal output from each of said first and second solid state imaging devices using said driving signal applied thereto to produce a given picture signal.