Electronic endoscope system with functionally alterable operable members

1. An electronic endoscope system used for observing living tissues inside a body cavity, comprising:

an illuminating apparatus having a white light source emitting white light and an excitation light source that emits excitation light having a predetermined wavelength, the living tissues emitting autofluorescence when irradiated with the excitation light;

an electronic endoscope, which includes:

an insertion part configured to be inserted into the body cavity;

a light guide configured to guide the white light and the excitation light to a distal end of the insertion part via the insertion part;

an imaging device configured to receive an optical image and output image signals corresponding to the received optical image;

an image forming system configured to form the optical image of the living tissues illuminated with each of the white light and the excitation light on the imaging device;

an operating part provided at a rear anchor of the insertion part; and

a plurality of operable members arranged at the operating part;

a display device;

an image processing system that receives the image signals outputted from the imaging device, the image processing system obtaining a normal image when the living tissues are illuminated with the white light and a fluorescence image when the living tissues are irradiated with the excitation light; and

a control system configured to control the whole of the electronic endoscope system,

wherein the control system assigns a function to one of the plurality of operable members for switching between a normal mode for observing the normal image and a fluorescence mode for observing the fluorescence image, and

wherein the control system assigns different functions between the normal mode and fluorescence mode to at least one of the others of the plurality of operable members.

2. The electronic endoscope system according to claim 1 ,

wherein the at least one of the others of the plurality of operable members includes:

a first operable member to which a first function is assigned in the normal mode;

a second operable member to which a second function is assigned in the normal mode; and

a third operable member to which a third function is assigned in the normal mode,

wherein a fourth function for the fluorescence mode is assigned to one of the first, second, and third operable members,

wherein a fifth function for the fluorescence mode is assigned to another one of the first, second, and third operable members, and

wherein at least one of the first, second, and third functions is assigned to the other of the first, second, and third operable members in the fluorescence mode.

3. The electronic endoscope system according to claim 2 ,

wherein the first function is a function for giving an instruction of talking a still image,

wherein the second function is a function for giving an instruction of printing out an image,

wherein the third function is a function for giving an instruction of recording a moving image,

wherein the fourth function is a function for giving an instruction of turning up brightness of a fluorescence image, and

wherein the fifth function is a function for giving an instruction of turning down brightness of a fluorescence image.

4. The electronic endoscope system according to claim 3 ,

wherein the image processing system includes:

a pre-signal-processing element that processes the image signals received from the imaging device;

at least two image memories that temporarily store the image signals outputted from the pre-signal-processing element; and

a post-signal-processing element that transforms the image signals outputted from the image memories into standardized video signals which are allowed to be displayed on the display device.

5. The electronic endoscope system according to claim 3 ,

wherein the illuminating apparatus includes a rotary shutter provided in front of the white light source, the rotary shutter having a light transmitting area and a light blocking area, the white light intermittently illuminating the living tissues as the rotary shutter rotates.

6. The electronic endoscope system according to claim 5 ,

wherein the illuminating apparatus includes an excitation light source driver that is configured to be able to intermittently turn on/off the excitation light source synchronously with the blocking/transmitting, operation of the rotary shutter.

7. The electronic endoscope system according to claim 3 ,

wherein the image forming system comprises:

an objective lens configured to receive light from the living tissues and forms an image thereof; and

an excitation light cut filter provided between the objective lens and the imagine device,

wherein the excitation light cut filter eliminates the wavelength components equivalent to the excitation light from light directed to the imaging device from the objective lens.

8. The electronic endoscope system according to claim 7 , wherein the excitation light source emits near-ultraviolet light.

9. The electronic endoscope system according to claim 2 ,

wherein the image processing system includes:

a pre-signal-processing element that processes the image signals received from the imaging device;

at least two image memories that temporarily store the image signals outputted from the pre-signal-processing element; and

a post-signal-processing element that transforms the image signals outputted from the image memories into standardized video signals which are allowed to be displayed on the display device.

10. The electronic endoscope system according to claim 2 ,

wherein the illuminating apparatus includes a rotary shutter provided in front of the white light source, the rotary shutter having a light transmitting area and a light blocking area, the white light intermittently illuminating the living tissues as the rotary shutter rotates.

11. The electronic endoscope system according to claim 10 ,

wherein the illuminating apparatus includes an excitation light source driver that is configured to be able to intermittently turn on/off the excitation light source synchronously with the blocking/transmitting operation of the rotary shutter.

12. The electronic endoscope system according to claim 2 ,

wherein the image forming system comprises:

an objective lens configured to receive light from the living tissues and forms an image thereof; and

an excitation light cut filter provided between the objective lens and the imaging device,

wherein the excitation light cut filter eliminates the wavelength components equivalent to the excitation light from light directed to the imaging device from the objective lens.

13. The electronic endoscope system according to claim 12 , wherein the excitation light source emits near-ultraviolet light.

14. The electronic endoscope system according to claim 1 ,

wherein the image processing system includes:

a pre-signal-processing element that processes the image signals received from the imaging device;

at least two image memories that temporarily store the image signals outputted from the pre-signal-processing element; and

a post-signal-processing, element that transforms the image signals outputted from the image memories into standardized video signals which are allowed to be displayed on the display device.

15. The electronic endoscope system according to claim 1 ,

wherein the illuminating apparatus includes a rotary shutter provided in front of the white light source, the rotary shutter having a light transmitting area and a light blocking area, the white light intermittently illuminating the living tissues as the rotary shutter rotates.

16. The electronic endoscope system according to claim 15 ,

wherein the illuminating apparatus includes an excitation light source driver that is configured to be able to intermittently turn on/off the excitation light source synchronously with the blocking/transmitting operation of the rotary shutter.

17. The electronic endoscope system according to claim 1 ,

wherein the image forming system comprises:

an objective lens configured to receive light from the living tissues and forms an image thereof; and

an excitation light cut filter provided between the objective lens and the imaging device,

wherein the excitation light cut filter eliminates the wavelength components equivalent to the excitation light from light directed to the imaging device from the objective lens.

18. The electronic endoscope system according to claim 17 , wherein the excitation light source emits near-ultraviolet light.