JPS622927A - Light source apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a light source device used when photographing in a frame sequential manner in, for example, an endoscope that photographs color images using a solid-state image sensor.

[Conventional technology]

In recent years, a solid-state imaging device such as a CCD is sometimes provided at the tip of an insertion section of an endoscope to perform color photography. In this case, C
Because a solid-state image sensor such as a CD is installed in an extremely narrow space at the tip of the insertion tube of an endoscope, it is impossible to increase the number of pixels no matter how you try. For this reason, a frame sequential method is used in which all pixels can be used for ringing. As shown in Japanese Unexamined Patent Publication No. 59-151591, this field sequential method rotates a wheel (turret) equipped with three filters that separate and transmit the three colors of red, green, and tee on the illumination light source side. By doing so, the illumination light is separated into each color of illumination light and sequentially illuminated. A component image of each color is obtained by this tl, and a video signal of a color image is generated by synthesizing the component signals of three colors for each image accumulation.

[Problem that the invention seeks to solve]

In the case of the above method, light is not transmitted during the entire rotation of the wheel, but there is no light during the shading period between the filters of each color. [7] This blanking period is used to read out the image signals of each color, but in order to perform this reading accurately, the blanking period must be extended for a relatively long time. Furthermore, when the light passes through each filter, it becomes an illumination device in which only the light of that color component is transmitted.

As mentioned above, the above-mentioned method has the essential drawback that the illumination light from the decorative lamp cannot be used effectively, and the brightness of the image photographed in color is relatively low.

By the way, in the case of an endoscope, the illumination light is originally small because a long light guide with a small diameter is used to guide the illumination light into the observation field. Therefore, the tendency for the brightness of photographed images to become low may become a serious problem. For example, depending on the situation inside the body cavity, color ii! The brightness of the li image may not be sufficient, making observation and diagnosis itself difficult. The same problem also occurs when the illumination lamp burns out and is replaced with a low-intensity spare lamp, so that the brightness of the illumination lamp itself becomes dim.

[Purpose of the invention]

The present invention has been made by focusing on the above-mentioned problems, and the brightness of the illumination light is selectively brightened to 1-7 for clear observation.
An object of the present invention is to provide a light source device that can secure an i-image.

[Failure to solve the problem]

The present invention provides an emission light path from the illumination light source 1 to the turret 6.
A moving mechanism for selectively retracting the filters 11, 12, and 13 is also provided.

[Effect]

In color photography, when the image is too dark, the turret 6 and the filter 11.degree.

As a result, the entire amount of light emitted from the illumination vanguard 1 is directly sent to the photographing device side for bright illumination.

〔Example〕

FIG. 1 shows a first embodiment of the invention.

1 in the frontage is a lamp for illumination.

The light emitted from this lamp 1 is turned into a flat beam on the output optical path by the condensing lens 2 at the front stage, and is further focused by the condensing lens 3 at the rear stage, after which an interline transfer type solid-state image sensor is used. The light is incident on an incident end face 5 of a light guide of an endoscope, for example, on the imaging device side.

A peripheral portion of a turret 6 is interposed between the condensing lenses 2 and 3 on the output light path. This turret 6 is pivotally supported by a support frame 7 and rotationally driven by a motor 8.

In addition, red (R) is concentrically arranged around the turret 6.
Green (G).

1iJ(B) filters 11, 12, and 13 of each color are provided discontinuously.

Further, this turret 6 constitutes a turret unit 14 together with a motor 8 and a support frame 7, which are installed so as to be movable in one direction. This turret unit 14 is moved by a solenoid 15 connected to its support frame 7, and its turret 6 is retracted from the output light path.In other words, the plunger 16 of the solenoid 15 is connected to the support frame 7, and its solenoid By energizing the turret unit 15, the support frame 7 is pulled, and the entire turret unit 14 is evacuated to the side.When the turret unit 17 is evacuated to the side, the turret 6 and the filters 11, 12 . 13 are withdrawn from the output optical path.

Note that a filter lens unit 17 is mounted on the support frame 7.
are integrally attached. lens unit 1 with
A filter lens 18 is provided at 7, and when the output optical path LK turret 6 is positioned, the filter lens 18 is also positioned at 1 o'clock.

Next, the operation of this embodiment will be explained. First, when photographing a color image normally, the turret unit 14
is advanced to the position shown in Figure 1. As a result, the peripheral portion of the turret 6 is located on the outgoing light path. When the tar 1/6 is rotated, each of the filters 11, 12, 13 is sequentially positioned on the output light path, and the light from the lamp J is transmitted therethrough, thereby being colored sequentially. The light of each color enters the light guide 4 of the endoscope from its entrance end face 5. Then, by illuminating the observation field, component images of each color are captured by the solid-state image sensor of the endoscope.

Still, the image signals are combined into a color video image and displayed on a monitor (11).

By the way, when the lamp 1 burns out and is replaced with a spare one, the brightness of the spare lamp V,1 generally decreases and the observation field becomes dark. Furthermore, the observation field becomes dark depending on the conditions of the observation field. However, 1-2, observation field of view is important for accurate diagnosis! ! There are times when I want to make the I-image brighter for observation. In such a case, by energizing the solenoid F15, the
L, evacuate the turret 6 from the output light path. Therefore, the light from the lamp 1 does not pass through the filters 11, 12, 13, and is not blocked by the members of the turret 6. That is, all the light 9 of the lamp 1 is incident on the incident end face 5 of the IT light guide 4. For this reason, the number of illumination light ports increases,
This brightly illuminates the observation field, making the photographed image brighter and clearer. I wanted to ``C1 10j11 examination 1
Do not interfere with 111. However, these days images are not in color but in black and white.

FIG. 2 shows a second embodiment of the invention. This embodiment consists of a rack 21 provided on the turret unit 14 side as a mechanism for moving the turret unit 14, and a pinion 22 that engages with the rack 21.
2 to be driven by motor 23 [also. In other words, by operating the motor 23, the rack 2) and the pinion 2 are
The turret unit 14 can be reciprocated via 2f.

FIG. 3 shows a third embodiment of the invention. This embodiment is a modification of the moving mechanism, in which the turret knot unit 14 is movably supported by a rail 25, and an operating lever 26 is provided so that the turret unit 14 can be manually operated by the operating lever 26. It is something that moves.

FIG. 4 illustrates a fourth embodiment of the present invention. This embodiment also shows a modification of the moving mechanism, in which the turret 6 is pivotally supported at one end of the lever 3, and
The J end of the lever 3 is connected to a plunger 33 of a solenoid 32, and when the solenoid 32 is energized, the plunger 33 is pulled to retract the turret 6 from the output light path. 'Furthermore, when the turret 6 is placed on the output light path, a gear portion 34 formed locally on the turret 6 meshes with the pinion 35. Then, the pinion 35 is connected to the motor 36.
The turret 6 is rotated by driving the turret 6.

〔Effect of the invention〕

As explained above, in the present invention, when the observed image is too dark for a single color curved image, the movement mechanism evacuates the turret and filter from the output optical path, so the amount of illumination light does not decrease and the entire amount of light can be sent. . Therefore, a bright image can be obtained with bright illumination.

[Brief explanation of the drawing]

1 to 4 are the first and second sections of the present invention, respectively. FIG. 7 is a perspective view showing third and fourth embodiments. DESCRIPTION OF SYMBOLS 1...Lamp, 4...Light guide, 5...Incidence end surface, 6...Turret, 7...Support frame, 8...
motor. 11...filter, 12...filter, 13...
Filter, 14...Turret unit, 15...
Solenoid, 16... Plunger, 21... Rack, 22... Binion, 23... Motor% 25...
·rail. 26...Operation lever, 3...Lever, 32...
Solenoid, 33... Plunger, 35... Binion, 36... Motor.

Claims (1)

[Claims] A light source device that sends illumination light of each color to a device that sequentially photographs component images of each color in a field sequential method, the illumination light source;
An output optical path that sends the light from the illumination light source to the photographing device; a turret that sequentially positions filters of each color on the output optical path; and a turret that selectively retracts the turret and the filters from the output optical path. A light source device characterized by comprising a moving mechanism for moving.