JPH0510649B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light source device for an endoscope with improved light attenuation means.

If a high-intensity lamp such as a xenon lantern is used as the light source lamp of an endoscope light source device, if an endoscope that uses a light guide that is sensitive to heat, such as a rigid scope, is connected, the incident end face of the light guide may be burnt. Sometimes it happens. For this reason, conventionally, when connecting such types of endoscopes, a mesh filter was inserted into the optical path to reduce the amount of light.

By the way, although such a method can reduce the amount of light, it cannot solve the problem of light distribution. In other words, in the above-mentioned xenon lamp, etc., a member supporting the electrode is disposed in the optical path, so the electrode supporting member blocks light and creates a shadow, and the light distribution of the light emitted from the light guide of the endoscope is As shown by curve C in the figure, there was a hollow state and the light distribution was not good.

The present invention has been made focusing on the above circumstances,
The purpose is to provide a light source device for an endoscope that can reduce the amount of light and at the same time improve the output light distribution characteristics of the light guide of the endoscope.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

1 in FIG. 1 is a front panel of this light source device for an endoscope. A socket 2 passing through a part of the front panel 1 is attached. A connector 3 provided at the extending end of the light guide cord of the endoscope is detachably connected to the socket 2. A light guide tube 4 is protruded from the connector 3, and the entrance end of the light guide of the endoscope is inserted into the light guide tube 4. The light guide is composed of an optical fiber bundle. The light guide tube 4 is arranged so that when the connector 3 is attached to the socket 2, the light guide tube 4 is positioned on an output optical path l of a light source lamp 5, which will be described later. The light source lamp 5 is a high-intensity lamp,
For example, a xenon lamp is used. A condenser lens 6 is installed on the output optical path l to condense the light from the light source lamp 5 and make it enter the input end surface 4a of the light guide tube 4. This condensing lens 6 is supported by a lens support frame 7. Furthermore, one circumference of a turret 8 of the switching operation mechanism is located between the light source lamp 5 and the condenser lens 6 and on the output optical path l. As shown in the figure, a filter 9, a through hole 10,
Emergency lights 11 and dimming ground glass 12 are arranged at intervals in the circumferential direction. By appropriately rotating the turret 8, one of them can be selectively interposed on the output optical path l. Further, the turret 8 is rotationally driven by a drive motor 14 which can freely rotate in forward and reverse directions via a gear train 13. Further, a position detecting disk (not shown) is provided on the rotating shaft 8a of the turret 8, and the filter 9 and the through hole 1 are provided on the side circumferential surface of this disk.
Identification marks corresponding to the positions of 0, the emergency light 11, and the dimming ground glass 12 are attached. By reading the identification mark with a mark reader (not shown), the drive motor 14 is controlled and the rotational position of the turret 8 is selected.

Furthermore, as shown in FIG.
There is a receiving bar 1 protruding toward the frame 15 on the periphery of the frame 15.
6 is attached. A stopper 17 is formed on the frame 15, located on the locus along which the receiving bar 16 moves, and is formed by a rising plate formed by cutting and raising a plate portion of the frame 15. With this stopper 17 in between, a first
and the actuator 18 of the second switch 18, 19
a, 19a is located. These switches 18 and 19 are arranged so that when the turret 8 rotates in either the left or right direction and passes the end of its rotation, the receiving bar 16 is activated by one of the actuators 18a and 19a.
is operated, and this signal causes the drive motor 14 to
The direction of rotation is reversed. Further, when the receiving bar 16 exceeds the actuators 18a and 19a, it hits the stopper 17 and prevents the turret 8 from rotating.

On the other hand, as shown in FIGS. 1 and 3, shutter blades 21 and aperture blades 22 are provided so as to be selectively interposed on the output optical path l between the socket 2 and the condensing lens 6. There is. The shutter blades 21 are driven by a rotary solenoid 24, and the aperture blades 22 are driven by an aperture motor. In FIG. 3, reference numerals 25 and 25 designate dampers that regulate the positions of both ends of rotation of the shutter blade 21. Note that, as shown in FIG. 1, the aperture blade 22 is located closer to the light source lamp 5 than the shutter blade 21 is.

The aperture blade 22 is made of a ground glass plate 26, and the roughness of the ground glass plate 26 is gradually changed along the direction of rotation, thereby gradually changing the transmittance. In other words, by changing the position of the ground glass plate 26 on the output optical path l, the amount of light transmitted changes. With this configuration, compared to a method in which the amount of transmitted light is changed by changing the width of the slit, the transmission range is greatly expanded, so that the light distribution can be improved.

Further, a heat ray absorption filter 27 is provided on the output optical path l between the light source lamp 5 and the turret 8.
is inserted.

By the way, when using an endoscope (for example, a rigid endoscope) that cannot handle high-intensity lamps as the light source device, when the connector 3 is inserted into the socket 2, an endoscope identification detector (not shown) detects whether the endoscope is connected to the endoscope. Something is detected. This detection method involves electrically detecting an identification resistor provided on the endoscope side on the light source device side through electrical contacts provided on the socket 2 and the connector 3. When the endoscope is detected in this way, the drive motor 14 starts rotating in response to an instruction from the drive control section, and until then the filter 9 or the through hole 10 was located on the output optical path l. This time, the ground glass 12 for dimming is placed in its place. That is, the ground glass 12 for dimming is automatically positioned on the output optical path l. Thereafter, when the light source lamp 5 is turned on and the shutter blade 21 is opened, the light from the light source lamp 5 passes through the dimming ground glass 12 and is attenuated at this time. Next, condenser lens 6
The light enters the light guide tube 4 from the incident end surface 4a.

Thus, the light attenuated by the ground glass 12 enters the light guide side of the endoscope, thereby preventing the light guide tube entrance end surface from being burnt. Furthermore, since the light passes through the ground glass 12, the light is scattered to some extent. Therefore, as shown in FIG. 4, the illuminance distribution of the spot S emitted from the light guide of the endoscope 28 has a desirable shape with no hollow spots, as shown by B in FIG. Incidentally, C in FIG. 5 is a case where light is attenuated using a conventional mesh filter. Further, A in FIG. 5 shows the illuminance distribution of the spot S without dimming.

In the above embodiment, only one type of ground glass 12 was prepared, but by separately preparing glasses with different transmittances and attaching them to the turret 8, for example, it is possible to switch to a different amount of light.

Further, in the above embodiment, when a predetermined type of endoscope is attached to the socket 2, the output optical path l is automatically changed.
This is convenient because the frosted glass 12 can be placed on top.

As explained above, in the present invention, a ground glass with a light attenuation property can be selectively interposed on the output optical path, so when light attenuation is required, by interposing the ground glass, the amount of light can be switched and the internal vision can be adjusted. The output light distribution of the mirror light guide can be improved.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a side sectional view of the main parts thereof, FIG. 2 is a rear view of the turret part, and FIG. 3 is a sectional view taken along the line - in FIG. 1. FIG. 4 is a schematic configuration diagram for explaining the illuminance distribution, and FIG. 5 is a graph diagram showing the illuminance distribution of a spot emitted from the light guide of the endoscope. 5... Light source lamp, 8... Turret, 9...
Ground glass for dimming.

Claims (1)

[Claims] 1. In a light source device for an endoscope in which light from a light source lamp is incident on a light guide of an endoscope, a dimming ground glass is supported by a switching operation mechanism, and the switching operation mechanism switches the ground glass from the light source lamp to the light source lamp. A light source device for an endoscope, characterized in that the light source device is selectively interposed on an emission light path of the light source device.