JPH01277812A - Microscopic device - Google Patents

Abstract

PURPOSE:To reproduce a stereoscopic and sharp image by disposing an objective lens in such a manner that the optical axis thereof has a prescribed angle with the optical axis of a condenser lens and allowing the luminous flux from the objective lens to enter image sensors by each line. CONSTITUTION:A sample 7 is two-dimensionally scanned in a main scanning direction and the auxiliary scanning direction intersecting orthogonally therewith by a spot-like light beam entering at 45 deg. incident angle. The objective lens 10 is so disposed as to face the condenser lens 6 at 45 deg. angle with the normal of the incident face of the sample 7 and the reflected light from the sample 7 is condensed by the lens 10. The luminous flux from the lens 10 is allowed to enter like a very small spot onto the linear image sensors 12 via an imaging lens 11. Since the sensor 12 have a charge accumulation effect, the image distortion is eliminated even if the unequal scanning speed in the main scanning direction is generated by an acousto-optical element 3. The surface condition of the sample is thereby three-dimensionally reproduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a microscope device that can three-dimensionally reproduce a sample to be observed.

(Prior art) A beam that scans a sample two-dimensionally with a light beam focused into a spot, receives reflected light or transmitted light from the sample with a photoelectric conversion device, and reproduces an image based on this photoelectric output signal. A scanning microscope device has been put into practical use, and is described, for example, in Japanese Patent Application No. 60-76611 proposed by the applicant. In this microscope device proposed by the applicant, a light beam emitted from a laser light source is two-dimensionally deflected by a main scanning deflection bag W and a sub-scanning deflection device, and this deflected light beam is focused into a spot by an objective lens. The spot light beam is projected onto the sample, thereby scanning the sample two-dimensionally with the spot-shaped light beam. Then, the reflected light from the sample is focused by the same objective lens, the luminous flux from the objective lens is projected onto the linear image sensor, and the charges accumulated in each light receiving element of the linear image sensor are read out at a predetermined readout frequency. Generating a photoelectric output signal. The beam scanning microscope device proposed by the applicant is a linear imager.
The structure utilizes the charge accumulation effect of the sensor to read out the charges accumulated in each element at a predetermined readout frequency, so it has the great advantage of being able to reproduce clear images without image distortion due to unevenness in the main scanning speed. It can be achieved.

(Problems to be Solved by the Invention) The above-mentioned microscope device has one objective lens arranged on the extension of the normal line to the sample entrance plane, and uses this objective lens to project a light beam toward the sample and to emit light from the sample. It is configured to condense a luminous flux. For this reason, although a two-dimensional image of the sample can be clearly reproduced, it is difficult to reproduce the sample three-dimensionally.

In other words, when there are irregularities on the sample surface, the presence of these depressions or protrusions can be clearly reproduced, but it is difficult to reproduce the protrusions or depressions three-dimensionally, and some empirical techniques are required to determine whether they are depressions or protrusions. was needed. Furthermore, depending on the sample to be observed, there is a strong desire to obtain image information viewed from the side of the sample, and there is a need to satisfy this demand.

Furthermore, in a configuration in which one objective lens is used and this objective lens is used both as a condensing lens for beam projection for illumination and as an objective lens for condensing a luminous flux emitted from a sample, there is a limit to the numerical aperture of the objective lens. There is also a strong demand to increase the numerical aperture from the viewpoint of image resolution and brightness.

Accordingly, an object of the present invention is to eliminate the above-mentioned drawbacks and provide a microscope apparatus that can three-dimensionally reproduce a sample surface and obtain a large numerical aperture.

(Means and Effects for Solving the Problems) A microscope apparatus according to the present invention includes a light source that emits a light beam, deflection means that deflects the light beam emitted from the light source in the main scanning direction at a predetermined scanning frequency, and A condenser lens that projects a spot toward the sample, and a 0° angle to the optical axis of the condenser lens.
and at least one objective lens arranged at an angle other than 180° and condensing the light beam from the sample;
A linear image sensor in which a plurality of elements are arranged one-dimensionally in a direction corresponding to the main scanning direction and receives a light beam emitted from an objective lens and outputs a photoelectric output signal at a predetermined readout frequency; A special feature is that the sample drive device is provided with a sample drive device that is driven in a direction orthogonal to the sample drive device.

In this way, the present invention uses a condenser lens that projects spot illumination light and an objective lens that condenses the light beam from the sample, and the optical axis of the objective lens is set at a predetermined angle with respect to the optical axis of the condenser lens. The linear image sensor is arranged so as to form a linear image sensor, and the light beam from the objective lens is made incident on the linear image sensor line by line. As a result, it is possible to reproduce three-dimensional images of the sample viewed from various directions, and also to reproduce clear images without image distortion. Furthermore, by arranging multiple objective lenses around one condenser lens, images viewed from multiple directions can be simultaneously reproduced and the numerical aperture of the objective lens system can be equivalently increased. can.

(Example) FIG. 1 is a diagram showing the configuration of an example of a microscope apparatus according to the present invention. A light beam emitted from a laser light source 1 is expanded into a parallel light beam by an expander 2, and this expanded parallel light beam is made incident on an acousto-optic element 3. This acousto-optic element 3 vibrates a light beam at high speed in the main scanning direction, and the sample is scanned at high speed in the X direction (direction perpendicular to the plane of the paper) by the high speed vibrating light beam. The light beam deflected by this acousto-optic element 3 is transmitted through relay lenses 4 and 5.
The light enters the condenser lens 6 through the condenser lens, and is focused into a minute spot by the condenser lens, and then enters the sample 7. The condensing lens 6 is arranged so that its optical axis forms an angle of, for example, 45° with respect to the normal to the incident surface of the sample 7. The sample 7 is mounted on a sample stage 8, and the sample stage 8 is deflected by a sample drive device 9 in the X direction (direction of the paper) perpendicular to the main scanning direction with a sawtooth wave of, for example, 608 g. This sample driving device 9 has an arm 9a, a motor 9b, and a conversion mechanism that converts the rotation into vibration.The rotation of the motor 9b is converted into vibration via the conversion mechanism, and the vibration causes the arm 9a to move in the direction indicated by the arrow a in the paper.
The sample 7 and the sample stage 8 are vibrated in the direction b and
is moved back and forth within the paper at a predetermined rate. Furthermore, sample 7
Since the amount of movement is extremely small compared to the arm length of the arm 9a, the movement of the sample 7 can be regarded as almost linear movement, and will not have any adverse effect on the focal state. Therefore, the sample 7 is two-dimensionally scanned in the main scanning direction and the sub-scanning direction perpendicular thereto by the spot light beam incident at an incident angle of 45°.

In this example, it is assumed that optical information about the sample is obtained by condensing reflected light from the sample. 45 to the normal to the plane of incidence of sample 7
An objective lens IO is arranged so as to face the condensing lens 6 at an angle of .degree., and the reflected light from the sample 7 is condensed by the objective lens 10. Then, the light beam from the objective lens 10 is passed through the imaging lens 11 to the linear image sensor 1.
2 in the form of a minute spot. This linear image sensor 12 is arranged at the imaging position of the imaging lens 11,
Each light receiving element is arranged one-dimensionally in a direction corresponding to the X direction so as to receive the reflected light from the sample 7 line by line in the main scanning direction, and each element receives the reflected light from the sample 7. Performs photoelectric conversion. Then, the charges accumulated in each element are read out at a predetermined readout frequency to generate a photoelectric output signal. Since this linear image sensor 12 has a charge accumulation effect, there is always a one-to-one correspondence between the pixels of the sample 7 and each light-receiving element constituting the linear image sensor, and the acousto-optic element 3 Even if scanning speed unevenness occurs, the amount of received light changes only slightly, and therefore, the inconvenience of image distortion can be eliminated. If you configure it like this,
Image information viewed from the side of the sample is also reproduced, making it possible to reproduce the surface state of the sample three-dimensionally.

FIG. 2 is a circuit diagram showing the configuration of an example of the drive circuit. A synchronization circuit 20 for forming vertical and horizontal synchronization signals (1) and (H) is connected to a clock generation circuit 21 to supply a horizontal synchronization signal (H). The clock generation circuit 21 forms clock pulses for reading out the charges accumulated in each element of the linear image sensor 12 based on the supplied horizontal synchronizing signal H, and uses the clock pulses for reading out the charges accumulated in each element of the linear image sensor 12. Supply to 12. The synchronization circuit 20 is connected to an acousto-optic element drive circuit 22 that controls the drive of the acousto-optic element 3 to supply a horizontal synchronization signal H, and is also connected to a sample drive circuit 23 that controls the drive of the sample drive device 9. Vertical synchronization signal■
Further, the processor circuit 24 is connected to supply a vertical synchronizing signal (2) and a horizontal synchronizing signal (H).

In the linear image sensor 12, the amount of charge corresponding to the amount of reflected light from the sample 7 is accumulated in each element, so these amounts of charge are read out in synchronization with each other based on the readout clock pulse. The signals are amplified through the amplification filter 25, and a vertical synchronization signal (2) and a horizontal synchronization signal (H) supplied from the processor circuit 24 are applied to form an image signal.

Then, the image signal is supplied to the monitor 26 for display,
Record on VTR27. Note that the signal processing may be performed after the amplified photoelectric output signal is temporarily stored in the frame memory.

FIG. 3 is a diagram showing the configuration of a modified example of the microscope apparatus according to the present invention. The same members as those used in FIG. 1 will be described with the same reference numerals. A laser beam emitted from a laser light source 1 is expanded into a parallel beam by an expander 2, and is deflected in the main scanning direction by an acousto-optic element 3. The deflected beam passes through the relay lens 4, the deflection prism 30, the λ/4 plate 31, and the relay lens 5, and enters the condenser lens 6, and is projected onto the sample 7 as a spot by the condenser lens. In this example, the condensing lens 6 is placed on the extension of the normal line to the incident surface of the sample 7, and the sample 7 is illuminated from the direction perpendicular to it. The condensing lens 6 not only projects the beam but also functions as an objective lens that condenses the light beam reflected by the sample 7. Furthermore, the first and second objective lenses 32 and 33 are arranged with the condenser lens 6 at the center so that their optical axes make an acute angle with the optical axis of the condenser lens 6, and the reflected light from the sample 7 is The reflected light reflected laterally is focused by first and second objective lenses 32 and 33. The sample 7 is reciprocated together with the sample stage 8 by a sample drive device 9 at a predetermined rate in a sub-scanning direction perpendicular to the main-scanning direction. Therefore,
In this example, the sample 7 is scanned two-dimensionally from the vertical direction with a spot-shaped light beam, and the reflected light reflected from the sample 7 in the lateral direction and the reflected light reflected in the vertical direction are focused. Image reproduction will be performed. The light beam reflected from the sample 7 toward the left side of the paper is focused by the first objective lens 32, passes through the imaging lens 34, and enters the first linear image sensor 35 as a minute spot. On the other hand, the reflected light reflected toward the right side of the page is focused by the second objective lens 33, passes through the imaging lens 36, and enters the second linear image sensor 37 as a minute spot.

Furthermore, the reflected light reflected in the vertical direction from the sample 7 is collected by a condensing lens 6, and a relay lens (imaging lens) 5
The light passes through the λ/4 plate 31, enters the polarizing prism 30, is reflected by the polarizing prism, and enters the third linear image sensor 38 as a minute spot. Then, the charges generated in each linear image sensor are read out at a predetermined readout frequency to generate three photoelectric output signals. With this configuration, one beam scan can scan the front direction and two directions.
It is possible to simultaneously reproduce three images viewed from one side. Then, signal processing is performed on each photoelectric output signal to generate three image signals. By combining three image signals through signal processing, image information viewed from three directions can be reproduced, and the numerical aperture of the objective lens system can be equivalently increased.

In addition, when reproducing images, the front image and side image of the sample can be reproduced separately by switching operations by the operator, or
It can also be played back as a composite image viewed from any direction.

The present invention is not limited to the embodiments described above, and various modifications and changes are possible. For example, in the above-described embodiment, the configuration is such that a reflected image of the sample is reproduced, but it is of course also possible to reproduce a transmitted image.

Further, in the above embodiment, the sample image was reproduced as a monochrome image, but main scanning is performed by combining three light beams using three light sources of red, green, and blue.

It is also possible to reproduce color images.

(Effects of the Invention) As explained above, according to the present invention, the optical axis of the objective lens is Since they are arranged at a predetermined angle with respect to the optical axis of the condensing lens, images of the sample viewed from various directions can be reproduced, and thus the sample image can be reproduced three-dimensionally.

Furthermore, by using a configuration in which multiple objective lenses are used to condense the light flux from the sample, images viewed from various directions can be simultaneously reproduced, and the numerical aperture of the objective lens system can be equivalently increased. can. .

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an example of the microscope device according to the present invention, FIG. 2 is a circuit diagram showing the configuration of a drive circuit, and FIG. 3 is a diagram showing the configuration of a modified example of the microscope device according to the present invention. be. 1... Laser light source 2... Expander 3...
Acousto-optic element 4.5... Relay lens 6... Condensing lens 7... Sample 8... Sample stage 9... Sample drive device 10...
・Objective lens 11...Imaging lens 12...Linear image sensor

Claims (1)

[Claims] 1. A light source that emits a light beam, a deflection means that deflects the light beam emitted from the light source in the main scanning direction at a predetermined scanning frequency, a condenser lens that projects the deflected beam as a spot toward the sample, and a condenser lens. 0° and 18 to the optical axis of
at least one objective lens arranged at an angle other than 0° and condensing the light beam from the sample, and a plurality of elements arranged one-dimensionally in a direction corresponding to the main scanning direction,
The method is characterized by comprising a linear image sensor that receives a light flux emitted from an objective lens and outputs a photoelectric output signal at a predetermined readout frequency, and a sample drive device that drives the sample in a direction orthogonal to the main scanning direction. Microscope equipment.