JPH0547038B2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a color imaging device.

(Prior Art) Conventionally, as an imaging device that converts optical image information of a sample into an electrical signal, solid-state imaging uses a two-dimensional array of light-receiving elements and sequentially reads signals from each light-receiving element to form an image signal. Imaging devices using such elements have been put into practical use. This imaging device using a two-dimensional solid-state image sensor uniformly irradiates the sample and projects the image of the sample onto the image sensor, and has a simple configuration.
It has the advantage of being able to obtain image signals, and has come to be used for various purposes.

Furthermore, as another imaging device, a light beam converged into a minute spot is deflected two-dimensionally to scan the sample surface, and the reflected light or transmitted light from the sample is detected by a photodetector such as a photo-detector. Optical scanning imaging devices that form optical information as image signals have been put into practical use. This optical scanning imaging device is configured to scan the sample with a microscopic spot-shaped light beam, so it is possible to prevent the generation of stray light, obtain high-resolution image signals, and adjust the brightness and contrast of the image electrically. It is adjustable and has a wide range of uses.

On the other hand, the conventional imaging device described above is a monochrome imaging device, and has the disadvantage that it cannot detect information regarding the color of the sample. Therefore, there is a strong demand for the development of a color imaging device with a simple configuration that can also detect information regarding the color of a sample.

(Problems to be Solved by the Invention) The imaging device having the above-mentioned configuration has the advantage of being able to take images with a simple configuration, but there are various problems when it is used as a color imaging device. For example, in an optical scanning type imaging device, it is difficult to scan a sample with light beams of three primary colors in a consistent manner, and there is a drawback that misalignment between the light beams in the horizontal and vertical directions, that is, color misalignment is likely to occur. For this reason, if a deviation occurs in the vertical direction, a registration error will occur, and if unevenness in the scanning speed occurs in the horizontal direction, the image of the three primary colors will be distorted, making it impossible to accurately reproduce the color information of the sample. was occurring. Furthermore, in order to scan the sample surface at high speed with a light beam, a highly sensitive photosensitive element must be used as a light receiving element, which has the drawback of making the apparatus larger and more expensive. On the other hand, in imaging devices using two-dimensional solid-state image sensors, it is difficult to obtain high-resolution image signals due to the low resolution of the two-dimensional solid-state image sensor, and the drawback is that the resolution is insufficient for applications such as defect inspection equipment. There is. In addition, two-dimensional solid-state image sensors have low sensitivity and require a powerful light source, which also has the disadvantage of increasing the size of the device.

The purpose of the present invention is to eliminate the above-mentioned drawbacks, and to provide a high-resolution image that can scan the three primary color light beams on a sample in a consistent manner, and that does not cause image distortion even if the scanning speed of each light beam varies. An image of
Moreover, it provides a small and inexpensive color imaging device.

(Means for Solving the Problems) A color imaging device according to the present invention includes a plurality of light sources that emit a plurality of light beams of different color components, and a plurality of light beams emitted from these light sources that are deflected in the main scanning direction. a first deflection means; a beam combining optical system that combines the light beams emitted from the first deflection means; and a beam deflection mirror, and directs the combined light beam in a sub-scanning direction perpendicular to the main scanning direction. an objective lens that converges the light beams deflected by the first and second deflection means into a minute spot shape and projects it onto the sample; A color separation optical system that separates the reflected light deflected by the deflecting means into each color component, and a plurality of light receiving elements arranged one-dimensionally in the main scanning direction, and each color component light reflected by the sample The present invention is characterized in that it includes a plurality of linear image sensors that respectively receive light through the color separation optical system and output photoelectric output signals in synchronization with each other.

(Function) In the present invention, each light beam of the three primary colors is vibrated at high speed in the X direction of the sample by the first deflection means, and each light beam is made incident on a common second deflection means to be perpendicular to the X direction. Deflect in the Y direction to 3
Combines primary color light beams into one light beam. This combined light beam is converged into a minute spot shape through an objective lens and projected onto the sample, and the sample is
Scan in the direction. Then, the reflected light or transmitted light from the sample is separated into each color component by a color separation optical system, and is made incident on a Niria image sensor arranged for each color component. Each linear image sensor has a plurality of elements aligned in a direction corresponding to the X direction, which is the main scanning direction.
The image sensors are arranged in a dimensionally arranged configuration, and each image sensor sequentially reads out the amount of charge accumulated in each element in synchronization and outputs a photoelectric output signal. With this configuration, it is possible to obtain a clear, high-resolution color image signal without image distortion or color shift in the horizontal and vertical directions.

(Embodiment) FIG. 1 is a diagram showing the configuration of an embodiment of a color imaging device according to the present invention. A red light source 1, a green light source 2, and a blue light source 3 are arranged to emit light beams of the three primary colors of red, green, and blue, respectively. In this example, a He-Ne laser that emits light with a wavelength of 633 nm is used as the red light source 1, and a 488 nm wavelength light is used as the green light source 2.
An Ar laser that emits light with a wavelength of m is connected to the blue light source 3.
A He-Cd laser that emits light at a wavelength of 442 nm is used. It is assumed that all the light beams emitted from the light sources 1 to 3 are linearly polarized. A light beam emitted from a red light source 1 is expanded into a parallel beam by an expander 4, reflected by a right-angle prism 5, and incident on a first acousto-optic element 6, which is a first deflection element.
This first acousto-optic element 6 vibrates a red light beam at high speed in the main scanning direction, and the red light beam vibrates at high speed to scan the sample surface in the X direction (perpendicular to the plane of the paper) at a scanning frequency f ₁ . do. The light beam deflected by the acousto-optic device 6 passes through relay lenses 7 and 8, passes through a first deflection prism 9 and a quarter-wave plate 10, which act as beam splitters, respectively, and then passes through a first Gikkreuzk prism 11. incident on .
This first dichroic prism 11 reflects only green light and transmits light in other wavelength ranges. The red light beam that has passed through this first dichroic prism 11 passes through a second dichroic prism 12 that reflects only blue light and enters a vibrating mirror 13 that is a second deflection element. This vibrating mirror 13 is commonly used for red light beam, green light beam, and blue light beam, and directs each light beam in the Y direction (direction of the paper) perpendicular to the X direction of the sample.
to be deflected. The red light beam reflected by the vibrating mirror 13 passes through relay lenses 14 and 15, and is converged into a minute spot by the objective lens 16.
7. As a result, the sample 17 is scanned by the red light beam in the form of a minute spot in the X and Y directions at a predetermined scanning frequency. In this example, optical information about the sample is obtained by detecting reflected light from the sample 17. The reflected light from the sample 17 is again focused by the objective lens 16, passes through the relay lenses 15 and 14, enters the vibrating mirror 13 again, is reflected by the vibrating mirror 13, and then passes through the second and first dichroic prisms 12. and 11, further passes through the 1/4 wavelength plate 10, and enters the first polarizing prism 9. The light flux incident on the polarizing prism 9 passes through the 1/4 wavelength plate 10 twice, so its polarization plane is rotated by 90°, and is reflected by the polarization plane 9a, passes through the first concave lens 18, and then passes through the first concave lens 18. The light enters the linear image sensor 19 in a converged state in the form of a minute spot. This linear image sensor 19 is placed at the imaging position formed by the relay lens 14 and the concave lens 18, and each element is arranged in the X direction of the sample (in the paper They are arranged one-dimensionally in a direction corresponding to the vertical direction), and each element receives the reflected light from the sample 17 and performs photoelectric conversion, thereby adjusting the readout frequency.
Read the charge accumulated in each element at _f2 . Since the linear image sensor has a charge accumulation effect, there is always a one-to-one correspondence between the pixels of the sample 17 and each light-receiving element constituting the linear image sensor 19, and the scanning in the main scanning direction by the acousto-optic element 6 Even if the speed is uneven, the amount of light received changes only slightly, and unlike conventional imaging devices that perform photoelectric conversion, image distortion does not occur.

Next, scanning with green light will be explained. The light beam generated from the green light source 2 passes through an expander 20 and a rectangular prism 21, and then is converted to the same frequency as the first acousto-optic element 6 by a second acousto-optic element 22.
The sample 17 is vibrated at high speed in the X direction at _f1 , and the sample 17 is scanned at high speed in the X direction at a scanning frequency _f1 . The green light beam deflected by the second acousto-optic element 22 passes through the relay lenses 23 and 24, passes through the second deflection prism 25, is reflected by the right angle prism 26, and is 1/
The light passes through the four-wavelength plate 27 and enters the first dichroic prism 11. Since this first dichroic prism 11 reflects only green light, the incident green light beam is reflected and enters a common optical path, passes through the second dichroic prism 12, and enters the vibrating mirror 13. . Then, it is deflected in the Y direction by the vibrating mirror 13 in the same way as the red light beam, passes through relay lenses 14 and 15, is focused into a minute spot by the objective lens 16, and enters the sample 17. As a result, the portion of the sample 17 scanned by the red light beam is simultaneously scanned by the green light beam. The reflected light from the sample 17 is again focused by the objective lens 16, passes through relay lenses 15 and 14, is reflected by the vibrating mirror 13, and is further reflected by the second dichroic prism 1.
2 through the first dichroic prism 11
reflect. Thereafter, it passes through the 1/4 wavelength plate 27 again, the polarization plane changes by 90°, is reflected by the right angle prism 26, and is further transferred to the polarization plane 25a of the second polarizing prism 25.
The light is reflected by the light beam and enters the half mirror 29 via the second concave lens 28 . The transmitted light is converged into a minute spot and enters the second linear image sensor 30, and the reflected light is reflected by the focus detection device 31.
The light is incident on the object lens 16 and used for focus detection of the objective lens 16. Like the first linear image sensor 19, the second linear image sensor 30 is arranged at the imaging position of the relay lens 14 and the second concave lens 28, and converts the reflected light from the sample 17 into one line in the main scanning direction. Each element is arranged one-dimensionally in a direction corresponding to the X direction of the sample 17 (direction perpendicular to the plane of the paper) so that light is received by each light-receiving element, and the reflected light from the sample 17 is received by each light-receiving element and photoelectrically converted. Assume that the charge stored in each element is read out at a readout frequency _f2 .

Next, scanning with blue light will be explained. The blue light beam emitted from the blue light source 3 is transmitted to the expander 32.
The light then passes through the right-angle prism 33, vibrates at high speed in the main scanning direction at a scanning frequency _f1 by the third acousto-optic element 34, passes through the relay lenses 35 and 36, passes through the third polarizing prism 37, and is reflected by the right-angle prism 38. , further passes through the 1/4 wavelength plate 39, is reflected by the second dichroic prism 12, enters a common optical path, and enters the common vibrating mirror 13, which converts the light into red and green light beams. Similarly, it is deflected in the Y direction. Further, the light passes through relay lenses 14 and 15 and is converged into a minute spot by an objective lens 16, and enters a sample 17. As a result, the red, green, and blue light beams are combined to form one scanning light beam, and the sample 17 is scanned in the X and Y directions by this scanning light beam. The blue reflected light from the sample 17 is again focused by the objective lens 16, passes through the relay lens 15 and the imaging lens 14, and enters the vibrating mirror 13. Then, it is reflected by this vibrating mirror 13, and the second
The light beam is reflected by the dichroic prism 12, deviates from the common optical path, passes through the 1/4 wavelength plate 39, the polarization plane changes by 90°, is reflected by the right angle prism 38 and the polarizing prism 37, and passes through the third concave lens 40. After that, the blue reflected light is converged into a minute spot and enters the third linear image sensor 41 which receives the blue reflected light. This third linear image sensor 41 is also arranged at the imaging position formed by the relay lens 14 and the third concave lens 40, and similarly to the first and second linear image sensors 19 and 30, it receives the blue reflected light from the sample 17. One element is placed in the direction corresponding to the X direction of the sample 17 so as to receive light for each line in the main scanning direction.
The elements are arranged dimensionally and are configured to read out the charges accumulated in each element at a readout frequency _f2 . Since the configuration is such that the vibrating mirror 13 is shared for the light beams of each color component, there is no deviation of the light beams in the vertical direction, and the occurrence of registration errors can be effectively prevented. FIG. 2 is a circuit diagram showing the configuration of an example of a vibration circuit. A synchronizing circuit 42 for forming vertical and horizontal synchronizing signals V and H is connected to a clock generating circuit 43 to supply a horizontal synchronizing signal H. The clock generation circuit 43 uses the first, second and third clock signals based on the supplied horizontal synchronizing signal H.
A clock pulse is formed to read out the charges accumulated in each element of the linear image sensors 19, 30, and 41, and this reading clock pulse is applied to the first, second, and third linear image sensors 1.
9, 30 and 41, respectively. Further, an acousto-optic element drive circuit 44 that controls the driving of the first, second, and third acousto-optic elements 6, 22, and 34 is connected to the synchronization circuit 42, and supplies a horizontal synchronization signal H. A vibrating mirror drive circuit 45 for controlling the drive of the mirror 13 is connected to supply a vertical synchronizing signal V, and a processor circuit 46 is further connected to supply a vertical synchronizing signal V and a horizontal synchronizing signal H. first, second and third linear image sensors 19,
30 and 41, the amount of charge corresponding to the amount of reflected light from the sample 17 is accumulated in each element, so these amounts of charge are read out in synchronization based on the readout clock pulse, and the linear image sensors 19,
Amplifiers 47, 48 and 4 connected to 30 and 41
9, respectively, and the processor circuit 46.
Each color image signal is formed by applying a vertical synchronizing signal V and a horizontal synchronizing signal H supplied from. Each color image signal is then supplied to the color monitor 50 for display or recorded on the VTR 51. With this configuration, three linear image sensors 1
Since the amount of charge is read out synchronously from 9, 30, and 41, image distortion can be effectively prevented.
In this example, the readout frequency f ₂ of the linear image sensors 19, 20, and 41 and the acousto-optic elements 6, 22
and 34 scanning frequencies _f1 are made to match, and the amount of electricity accumulated in each element of each Niria image sensor is read out in synchronization with the main scanning, but linear image sensors are equipped with a charge accumulation ability. Therefore, even if a deviation occurs between the scanning frequency f ₁ of the acousto-optic element and the readout frequency f ₂ of each linear image sensor, problems such as image distortion and color shift will not occur.

FIG. 3 is a plan view showing the relationship between the beam spot projected onto the linear image sensor and each element constituting the linear image sensor. In the present invention, three linear image sensors 19, 30 and 4 are used.
1 have the same configuration, the first linear image sensor 19 that receives red light will be explained. The reflected light from the sample 17 is projected onto the linear image sensor 19 in the form of a minute spot, but in this example, the diameter of the projected beam spot 55 is determined by the diameter of each element 1.
The spot diameter is configured to be slightly larger than that of the light receiving surfaces 9a to 19n. The projected beam spot 55 is sequentially deflected in the X direction, which is the arrangement direction of the elements 19a to 19n, so that the reflected light from the sample 17 is one-dimensionally received by each of the elements 19a to 19n, and is reflected from the sample 17. A charge corresponding to the amount of reflected light is accumulated in each element and converted into a photoelectric output signal. If the reflected light from the sample 17 is made to enter as a spot diameter larger than the light-receiving surface of each element of the image sensor 19 as in this example, if a positional error of the incident light with respect to the image sensor 19 occurs or external vibration becomes stable. In particular, when photographing with zoom, the spot diameter of the light beam is likely to change, so this is effective for an imaging device equipped with a zoom photographing function.

FIG. 4 is a graph showing the relationship between the readout frequency of the linear image sensor and the amount of charge accumulated in each element. In the embodiment described above, the scanning frequency f ₁ of the acousto-optic elements 6, 22, and 34 and the readout frequency f ₂ of the linear image sensors 19, 30, and 41 were in a 1:1 relationship, but the linear image sensor has a charge storage capacity. , there is no need for synchronization, and the scanning frequency f ₁ by the acousto-optic element can be set to be higher than the readout frequency f ₂ . This example shows an example that utilizes this charge accumulation effect. Figure 4A shows the case where the readout frequency _f2 of the linear image sensor is equal to the scanning frequency _f1 in the main scanning direction of the light beam, that is, the amount of charge accumulated in the element each time the sample is scanned once with the light beam. Figure B shows the amount of accumulated charge when the configuration is read out.
C shows the amount of accumulated charge when f ₁ = 2f ₂ , that is, when the sample is scanned twice with a light beam and then _the amount of charge accumulated in the element is read out.
3f ₂ , that is, the amount of accumulated charge is shown in the case of a configuration in which the sample is scanned three times with a light beam and then the amount of charge accumulated in the element is read out.

In this way, if the image sensors 19, 30, and 41 are configured to receive the reflected light from the sample 17 multiple times, the main scanning frequency _f1 of the light beam can be increased.
Compared to the case where the readout frequency f ₂ of the image sensor and the readout frequency f 2 of the image sensor are set equal, the influence of the noise of the light source is averaged out, so that the S/N ratio of the photoelectric output signal can be substantially improved. Of course, in this case, the readout frequency _f2 of the image sensor is always constant, and a signal at a predetermined television rate can be obtained.

In FIG. 4, the readout frequency of the image sensor is changed, but it goes without saying that the same effect can be obtained even if the readout frequency of the image sensor is kept constant and the scanning frequency of the acousto-optic element is changed.

Next, resolution will be explained. FIG. 5A is a diagram schematically showing the scanning state on a sample by the conventional optical scanning microscope imaging device, and FIG. 5B is a diagram schematically showing the scanning state on the sample by the microscope imaging device according to the present invention. FIG. In conventional optical scanning microscope devices, when using a light source with low output, the scanning speed must be slowed down and the scanning line density must be set low, resulting in the loss of optical information between the scanning lines. An inconvenience was occurring. On the other hand, if the scanning frequency f ₁ of the light beam in the main scanning direction is set to be approximately an integral multiple of the readout frequency f ₂ of the image sensors 19, 30, and 41, the main scanning speed can be increased and the scanning line density can be increased. However, it is possible to obtain a photoelectric output signal of approximately the same magnitude. As a result, the scanning line density can be set equivalently high without deteriorating the S/N ratio of the photoelectric output signal or slowing down the scanning speed of the light beam, making it possible to more accurately reproduce the optical information of the sample. . In particular, when inspecting pattern defects on photomasks and reticle patterns using conventional optical scanning microscopes, microscopic defects often exist between scanning lines and are often overlooked. Being able to set the line density to an equivalently high value is extremely effective for pattern defect inspection equipment.

Next, prevention of chromatic aberration will be explained.

In a color imaging device, a sample is irradiated with light beams of three primary colors through optical elements, so it is necessary to correct chromatic aberration caused by the optical elements. In this example, first to third concave lenses 1 are arranged movably in the optical axis direction in front of each linear image sensor 19, 30, and 41.
8, 28, and 40 in the optical axis direction, and also adjust the position of each linear image sensor in the optical axis direction to remove chromatic aberration. First, the optical system is set to be free of aberrations using green light, which is in the middle wavelength range of the three primary colors, as a reference. In this case, adjustment can be facilitated by changing the position of the second concave lens 28. In this state, the reflected light from the sample 17 is transmitted to the first and third linear image sensors 19 and 3.
The first and third concave lenses 18 and 36 are appropriately moved in the optical axis direction, and the positions of the linear image sensors 19 and 41 in the optical axis direction are adjusted so that an image is formed on the image sensor 7 with a predetermined beam spot diameter. to remove chromatic aberration for red and blue.

If chromatic aberration is removed using a concave lens as in this example, there is an advantage that the deflection angle of the light beam incident on each linear image sensor can be increased. Note that chromatic aberration can also be removed by using a variable magnification lens system instead of a concave lens.

Next, the configuration of the focus detection device 31 will be explained. In this example, focus detection is performed based on green reflected light in the middle wavelength range of the three primary colors. A part of the green reflected light is branched by a half mirror 29 disposed in the optical path of the green reflected light and made to enter the convex lens 60 . This convex lens 60 transmits the reflected light emitted from the sample 17 to the first to third linear image sensors 19,
28 and 37, and the light beam emitted from the convex lens 60 passes through the slit plate 6.
1 and enters the half mirror 62. Then, the transmitted light enters the first photodetector 63,
The reflected light enters the second photodetector 64. The first photodetector 63 is placed in front of the imaging point of the convex lens 60, and the second photodetector 64 is placed behind the imaging point. With this configuration, the light intensity distribution of the light beams incident on each of the photodetectors 63 and 64 varies depending on the out-of-focus state, so the first
It is easy to compare the photoelectric output values of the first photodetector 63 and the second photodetector 64 by regulating the light-receiving areas of the second photodetectors 63 and 64 to be smaller than the incident beam diameter. Focus can be detected.
In this way, a part of the observation light that enters the linear image sensor is branched and made to enter the focus detection device, and focus detection is performed using the direct observation light, so more accurate focus detection can be performed. .

FIG. 6 is a circuit diagram showing the configuration of an example of a control circuit of the focus detection device. First and second photodetector 6
3 and 64 are connected to a differential amplifier 65, and a difference in the amount of light received by the first photodetector 63 and the second photodetector 64 is detected to generate a focusing error signal. Then, this focusing error signal is sent to switch 6.
6 is supplied to an objective lens drive circuit (not shown) in a servo loop to shift the objective lens 16 in the a or b direction to automatically shift the objective lens 16 to the in-focus position. Further, in this example, a control circuit is also provided to avoid the inconvenience that the objective lens 16 is largely deviated from the in-focus position, making it impossible to control the drive of the objective lens. That is, the first and second photodetectors 63 and 64 are connected to the adder 67, a sum signal of the photoelectric outputs of the photodetectors is generated, inputted to the inverting output terminal of the comparator 68, and compared with the reference voltage V. , and supplies this output to the control terminal of switch 66. If the objective lens 16 deviates significantly from the in-focus position, the amount of light incident on each photodetector will drop significantly. Therefore, the reference threshold value and the corresponding reference voltage V are input to the comparator 68, and the sum signal is calculated from this threshold value. If is small, the output of the comparator 68 turns off the switch 66.
Then, the switch 66 is switched so that the common terminal 66a is connected to the volume 69. This volume 69 is connected to a power source (not shown) and supplies a drive output to the servo loop so that the objective lens 16 is located at the reference setting position. Then, set the volume at an appropriate position depending on the sample to be observed. With this configuration, even when changing the sample to be observed or switching between a reflected light image and a transmitted light image, the objective lens can be driven and controlled without malfunctioning.

The present invention is not limited to the embodiments described above, but can be modified and modified in many ways. For example, in the embodiment described above, three light beams of red, green, and blue are projected onto the sample, but a structure may be adopted in which two light beams, such as red and blue, are projected.

Further, in the above-described embodiments, the configuration is such that the image is taken using the reflected light from the sample, but it is also possible to use the configuration that the image is taken using the transmitted light from the sample.

Furthermore, _the scanning frequency f ₁ by the deflection means and the readout frequency f ₂ of the linear image sensor do not necessarily have to have an integral multiple relationship. Even if it is not an integer multiple, there will be no problem with the image.

Further, as a means for deflecting the light beam, any deflecting means such as a polygon mirror can be used.

Further, in the above-described embodiment, an acousto-optic element is arranged for each of the three primary color light beams, but it is also possible to make each primary color light beam incident on a single acousto-optic element and cause it to vibrate at high speed. In this case, the optimal angle of incidence on the acousto-optic element differs depending on the wavelength of the light, so each light beam is made incident on a single acousto-optic element by changing the angle of incidence within the same plane and deflected in the X direction. .
It is also possible to make the three primary color light beams incident on a single acousto-optic element along different planes. In this way, when using a single acousto-optic element,
An optical system is required to direct the light beams emitted from the acousto-optic elements in different directions into a common vibrating mirror, but since acousto-optic elements are expensive, the advantage of reducing the cost of the entire device can be achieved. .

(Effects of the Invention) The effects of the present invention explained above are summarized as follows.

(1) Since a vibrating mirror that performs sub-scanning is commonly used for each light beam, it is possible to prevent vertical color shift, that is, registration error.

(2) A linear image sensor with a charge accumulation effect is used as a photoelectric conversion element, and each linear image sensor is read out synchronously, so even if the scanning speed of the light beam changes, there will be no image distortion or color shift. can be completely prevented from occurring.

(3) If the scanning frequency of the light beam for each color component is set to be approximately an integral multiple of the readout frequency of the linear image sensor, the influence of noise from the light source will be averaged out, effectively increasing the S/N ratio. A color image signal can be obtained. Moreover, the scanning line density can be equivalently increased without slowing down the scanning speed of the light beam, and loss of optical information on the sample can be avoided. In particular, a linear image sensor can obtain 1000 pixels or more, so it can form a high-resolution color image signal.

(4) The focus detection device is placed between the linear image sensor and the sample, and a part of the observation light incident on the linear image sensor is branched to directly detect the focus using the observation light. The sample can be imaged with accurate focus.

(5) A lens system for changing magnification is arranged movably in the optical axis direction between the color separation optics and the linear image sensor, and chromatic aberration can be easily removed by adjusting the position of this lens system. .

(6) If a laser light source is used as the light source, a phase difference will occur due to the unevenness of the sample surface, and the unevenness of the sample surface can be clearly imaged due to the brightness and darkness caused by the interference effect.

(7) When observing biological samples, laser light can excite minute amounts of fluorescent components contained in living organisms, while linear image sensors are also sensitive to fluorescent regions, so a fluorescent filter is used. It is possible to accurately reproduce the biological image without any trouble.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of an example of a color imaging device according to the present invention, FIG. 2 is a circuit diagram showing the configuration of an example of a drive circuit, and FIG. 3 is a beam spot and elements projected onto a linear image sensor. 4A to 4C are graphs showing the relationship between the readout frequency of the linear image sensor and the amount of accumulated charge, and FIGS. 5A and B are diagrams showing the state of the scanning line on the sample. , FIG. 6 is a circuit diagram showing a circuit configuration of an example of a focus detection device according to the present invention. 1... Red light source, 2... Green light source, 3... Blue light source, 4, 20, 32... Expander, 5, 2
1, 26, 33, 38...Right angle prism, 6, 2
2, 34... Acousto-optic element, 7, 8, 14, 1
5, 23, 24, 35, 36...Relay lens,
9, 25, 37...Polarizing prism, 10, 27,
39...1/4 wavelength plate, 11, 12...Dichroic prism, 13...Vibrating mirror, 16...Objective lens, 17...Sample, 18, 28, 40...
Concave lens, 19, 30, 41... Linear image sensor, 29, 62... Half mirror, 31...
Focus detection device, 42... Synchronization circuit, 43... Clock generation circuit, 44... Acousto-optic element drive circuit,
45... Vibrating mirror drive circuit, 46... Processor circuit, 47, 48, 49... Amplifier, 50...
Color monitor, 51...VTR, 55...Beam spot, 60...Convex lens, 61...Slit plate, 63, 64...Photodetector, 65...Differential amplifier, 66...Switch, 67... ...Adder, 68...
...Comparator, 69...Volume.

Claims (1)

[Scope of Claims] 1. A plurality of light sources that emit a plurality of light beams of different color components; a first deflection means that deflects the plurality of light beams emitted from these light sources in the main scanning direction; a beam combining optical system that combines the light beams emitted from the deflection means; a second deflection means that has a beam deflection mirror and deflects the combined light beam in a sub-scanning direction orthogonal to the main scanning direction; an objective lens that converges the light beams deflected by the first and second deflection means into a minute spot shape and projects it onto the sample; a color separation optical system that separates each color, and a plurality of light receiving elements arranged one-dimensionally in the main scanning direction, and receives each color component light reflected by the sample through the color separation optical system. A color imaging device comprising: a plurality of linear image sensors that output photoelectric output signals in synchronization with each other. 2. A lens system is arranged between the color separation optical system and the linear image sensor so as to be movable in the optical axis direction, and the position of the lens system is adjusted to remove chromatic aberration. A color imaging device according to claim 1. 3. A plurality of light sources that emit a plurality of light beams of different color components, a beam combining optical system that combines the light beams emitted from the light sources, and a first deflection means that deflects the combined light beam in the main scanning direction. and a second deflection means having a beam deflection mirror and deflecting the light beam deflected by the first deflection means in a sub-scanning direction perpendicular to the main scanning direction; an objective lens that converges the light beam deflected by the deflection means into a minute spot shape and projects it onto the sample, and separates the reflected light reflected by the sample and deflected by the second deflection means into each color component. It has a color separation optical system and a plurality of light receiving elements arranged one-dimensionally in the main scanning direction, and each color component light reflected by the sample is transmitted through the second deflection means and the color separation optical system. A color imaging device comprising a plurality of linear image sensors that receive light and output photoelectric output signals in synchronization with each other. 4. A lens system is arranged between the color separation optical system and the linear image sensor so as to be movable in the optical axis direction,
4. The color imaging device according to claim 3, wherein the color imaging device is configured to remove chromatic aberration by adjusting the position of this lens system.