JP2974393B2 - Microscope image input device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image input device suitable for an autofocus type microscope that needs to capture images at high speed.

[Conventional technology]

Conventionally, in a microscope of this type, when an image of a specimen is captured and the degree of blur of the image at that time is determined to perform a focusing operation, the exposure amount of an image projected on an image sensor for capturing the specimen image In order to obtain an image, a method of increasing the charge accumulation time in the image sensor or removing an ND filter from an optical path to the image sensor to make the illumination brighter has been used. Furthermore,
An exclusive optical path for guiding a sufficient amount of light to the image sensor is separately provided to capture an image.

[Problems to be solved by the invention]

However, in the conventional image input device of a microscope, when the charge accumulation time of the image sensor is lengthened to obtain a sufficient exposure amount, first, the focus detection time is also correspondingly corresponding to the length of the charge accumulation time. It takes a long time, and furthermore, the image projected on the image sensor cannot be changed at high speed during the image input by the image sensor, so that the stage of the microscope cannot be moved at high speed during image capturing. The time required to move the stage or the like to the in-focus position is lengthened, and particularly in the case of an observation sample with a small amount of light, an extremely long time is required for auto-focusing, which is problematic in terms of practicality. was there. On the other hand, as described above, the method of rejecting the ND filter to secure the light amount or switching to the dedicated optical path for the image sensor not only requires time for switching the ND filter and the dedicated optical path. However, there is an inconvenience that the apparatus for that must be large.

In view of such circumstances, an object of the present invention is to provide an image input device capable of effectively realizing high-speed focus detection in this kind of microscope.

[Means for solving the problem]

As shown in FIG. 1, the image input device for a microscope according to the present invention includes an image sensor for capturing an image of an observation sample illuminated by a main light source, and a range of the observation sample for which the image sensor should capture the image. And an auxiliary light source for illumination.

Further, the auxiliary light source can switch between use and non-use or adjust the amount of light in accordance with the state of an image projected on the image sensor.

[Action]

According to the present invention, in FIG. 1, an image of a specimen which is illuminated suitable for observation by a main light source is projected on an image sensor by an imaging lens, but only in a range where an image of an auxiliary specimen is captured. To illuminate. Therefore, a sample image of a sufficient light quantity is always projected on the image sensor, and thereby, it is possible to effectively realize speedup and accuracy of focus detection.

Further, focus detection can be performed under optimal and rational conditions according to the image state on the image sensor.

〔Example〕

Hereinafter, a first embodiment of an image input device for a microscope according to the present invention will be described with reference to FIG. In the figure, 1 is an observation sample, 2
Is an objective lens, 3 is a main light source, 4 is a collimating lens, 5
Is a half mirror. Therefore, first, the illumination light emitted from the main light source 3 is applied to the observation sample 1 by the objective lens 2 through the half mirror 5. Further, 6 is a half mirror arranged on the optical path of the reflected light from the observation sample 1, 7 is an imaging lens,
8 is an image sensor. Here, in the above-described optical system, it is possible to perform focus detection by capturing the image of the observation sample 1 formed by the illumination light of the main light source 3 into the image sensor 8.

Further, in the figure, 9 is an auxiliary light source disposed on the optical path behind the main light source 3, 10 is a window member for setting an illumination range of the illumination light by the auxiliary light source 9, 11 is a condensing lens of the illumination light of the auxiliary light source, 12 Reference numeral denotes a shutter whose opening and closing are controlled so as to block the illumination light of the auxiliary light source 9. Here, the illumination light of the auxiliary light source 9 is transmitted through a window member.
10, the observation sample 1 is illuminated via the condenser lens 11, the collimating lens 4, the half mirror 5, and the objective lens 2.
10 has a window 10a similar in shape to the light receiving surface of the image sensor 8, and the illumination light of the auxiliary light source 9 illuminates only the area on the observation sample 1 where the image sensor 8 captures an image. I have.

In the above case, the shutter 12 is controlled to open and close so that the optical path of the auxiliary light source 9 is opened only when the image sensor 8 is capturing an image of the observation sample 1.

Since the image input device of the microscope according to the present invention is configured as described above, when the image sensor 8 captures an image of the observation sample 1, the shutter 12 is controlled by the control means to open the optical path of the auxiliary light source 9 as illustrated. , Whereby the auxiliary light source 9
Irradiates the illumination light from behind the main light source 3 via the condenser lens 11, and further illuminates the observation sample 1 via the observation lens 2 via the collimator lens 4, the half mirror 5 and the condenser lens 2. In this case, the illumination light of the auxiliary light source 9 passes through the window member 10 and is narrowed down by the window 10a so as to illuminate only the area where the image sensor 8 captures the image of the observation sample 1. Therefore, the observation sample 1 is simultaneously illuminated with the illumination light of the main light source 3 and the illumination light of the auxiliary light source 9 narrowed down to a certain range, whereby an image of a necessary and sufficient light amount is always projected on the image sensor 8. You. Since a bright image can be obtained quickly by the image sensor 8,
Focus detection can be performed at high speed and with high accuracy. Further, for example, by using the image sensor 8 as a line image sensor for autofocusing, the illumination light of the auxiliary light source 9 is irradiated onto the observation sample 1 for a short time in a limited narrow range. The influence on the illumination suitable for the observation to be performed can be almost eliminated.

FIG. 3 shows a second embodiment of the microscope image input device of the present invention. In the figure, the configuration of the optical system itself by the main light source 3 is basically the same as that of the first embodiment, but in the second embodiment, an infrared light emitting diode is used as the auxiliary light source 9 and the light of the auxiliary light source 9 is changed. Is incident on the half mirror 14
Is constituted by a mirror that reflects only infrared light, and the auxiliary light source 9 is turned on only for a certain period.

After the light emitted from the auxiliary light source 9 passes through the condenser lens 11,
The beam is squeezed by the window member 10 and enters the half mirror 14 via the collimator lens 13. Only the infrared light is reflected by the half mirror 14 and irradiates the observation sample 1. Is projected onto the image sensor 8. According to the second embodiment, in particular, the shutter 12 can be eliminated.

Next, in the third embodiment of the image input device for a microscope according to the present invention, the auxiliary light source 9 is configured so that its use / non-use can be switched according to the state of the image projected on the image sensor 8. . That is, FIG. 4 shows such an auxiliary light source 9.
1 shows a schematic configuration of an operation control system. In the figure, an image signal of the image sensor 8 is amplified by an amplifier 15 and then digitized by an A / D converter 16, and the digital signal is stored in an image memory 17. When performing focus detection, the central processing unit (CPU) 18 needs to turn on the auxiliary light source 9 by comparing the image signal stored in the image memory 17 with the image state at that time. It is determined whether or not. The result of this determination is sent to the auxiliary light source controller 19 as an operation control signal for the auxiliary light source 9.

According to the third embodiment, when the light amount of the image of the observation sample 1 projected on the image sensor 8 is small, the auxiliary light source 9 is used.
Is turned on and the auxiliary light source 9 is not turned on when the light amount is sufficient, and the use / non-use of the auxiliary light source 9 is switched according to the state of the image projected on the image sensor 8 in this way. Since the control is performed, the use frequency of the auxiliary light source 9 can be minimized, so that the main light source 3 does not affect the illumination suitable for the sample observation at all.

Further, in the fourth embodiment of the image input device of the microscope according to the present invention, the auxiliary light source 9 is configured such that the light amount thereof is adjusted according to the state of the image projected on the image sensor 8. That is, also in this case, the auxiliary light source 9 shown in FIG.
When focus detection is performed, the image signal of the image sensor 8 is amplified by an amplifier 15 and then digitized by an A / D converter 16. Is stored. And CP
U18 determines the optimal light amount of the auxiliary light source 9 by comparing the image signal stored in the image memory 17 with the image state at that time, and sends the determination result to the auxiliary light source control unit 19.

Also in the fourth embodiment, an image with an optimum light amount is projected on the image sensor 8 by adjusting the light amount of the illumination by the auxiliary light source 9.

〔The invention's effect〕

As described above, according to the image input device of the microscope of the present invention, by using the auxiliary light source, an image having a sufficient amount of light is always projected on the image sensor. To effectively realize Further, the illumination of the auxiliary light source is limited to a very narrow range of the observed image, and the illumination time is extremely short. Therefore, even if an image is simultaneously captured during the illumination of the auxiliary light source, the effect on the image is not affected. Can be almost eliminated.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing a main part configuration of an image input device of a microscope according to the present invention, FIG. 2 is a diagram showing a main part configuration according to a first embodiment of the image input device of the present invention, and FIG. FIG. 4 is a diagram showing a main part configuration of a second embodiment of the image input device of the present invention,
FIG. 5 is a block diagram showing an operation control system of an auxiliary light source according to a third embodiment of the image input device of the present invention. 1 observation specimen, 2 objective lens, 3 main light source, 4
…… Collimate lens, 5,6,14 …… Half mirror, 7…
... imaging lens, 8 ... image sensor, 9 ... auxiliary light source, 10 ... window member, 11 ... condensing lens, 12 ... shutter, 15 ... amplifier, 16 ... A / D converter, 17 …… Image memory, 18 …… CPU, 19 …… Auxiliary light source control unit.

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02B 21/00 G02B 21/36

Claims (3)

(57) [Claims] 1. An image sensor for capturing an image of an observation sample illuminated by a main light source, and an auxiliary light source for illuminating an area of the observation sample where the image sensor is to capture the image, wherein the auxiliary light source is An image input device for a microscope, wherein the observation sample is illuminated only when the image sensor is capturing an image of the observation sample. 2. A microscope image input device according to claim 1, wherein the use or non-use of said auxiliary light source can be switched in accordance with the state of an image projected on said image sensor. apparatus. 3. The image input device for a microscope according to claim 1, wherein the amount of light from the auxiliary light source can be adjusted in accordance with the state of an image projected on the image sensor. .