JP2003307678A - Imaging apparatus with compound prism optical system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus with a compound prism optical system which can correct a shift in imaging position due to an on-axis chromatic aberration generated owing to a difference in wavelength between visible light and invisible light due to variation in imaging magnification as an imaging apparatus having an imaging optical system whose imaging magnification is variable and which can realize a small size, simplicity and a low cost. <P>SOLUTION: The imaging apparatus is equipped with an imaging device for visible light and an imaging device for invisible light which photoelectrically convert an optical image of a subject formed by the imaging optical system whose imaging magnification is variable, a compound prism composed of a 1st prism, which has a reflecting surface with a film transmitting the wavelengths of the invisible light range and reflecting wavelengths of the visible light range and is fixed to a prism fixed base, and a 2nd prism which has a surface facing the reflecting surface of the 1st prism across a fixed gap, arranged in the optical paths between the imaging optical system and the imaging devices, a prism driving means which can move the 2nd prism along the reflecting surface of the 1st prism, and an imaging magnification data memory which stores previously set imaging magnification data of the imaging optical system. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup device such as a monitoring / measurement image pickup device or an image reading device, and uses a prism in the optical path of an image pickup optical system to separate a visible light image and an invisible light image. The present invention relates to an imaging device having a composite prism optical system capable of imaging.

[0002]

2. Description of the Related Art In an image reading apparatus for a film scanner that uses infrared light as invisible light, a subject such as a film is irradiated with illumination light so that light including image information of the subject is captured by an optical system. By projecting and forming an image on the light receiving surface of the photoelectric conversion element via the photoelectric conversion element and performing photoelectric conversion by the photoelectric conversion element, the image information from the subject is converted into an electric signal and read as image data. Also, in such a device, dust adhering to the illumination optical system and the imaging optical system, dust on the film, scratches, fingerprints, etc. appear as black dots on the read image data and are reproduced by the film scanner as a result. The image becomes defective and the image quality is deteriorated.

On the other hand, various methods have been proposed in which infrared light is used to automatically correct such defects in an image or to correct them sufficiently. This is focused on the infrared transmittance characteristics of the film,
This is a method in which only the dust, scratches, fingerprints, etc. that cause the above-mentioned image quality deterioration are detected by infrared light, and the image data of the subject read by visible light is corrected by the detected defect data such as dust, scratches, and the like.

However, in an image pickup optical system such as a lens, an optical path length shift occurs due to a difference in wavelength between visible light and infrared light, and an image plane formed by infrared light is generally farther than an image plane formed by visible light. Exists in.

Therefore, in Japanese Patent Publication No. 6-78992 (conventional example 1), a red, green, and blue color separation filters and an IR (infrared) filter are mounted on a filter holder to rotate them to form a three-primary-color image. The IR image is sequentially read by one photoelectric conversion element, but when the IR image data is read by the IR filter, the driving mechanism slightly changes the sensor (photoelectric conversion element) in the optical axis direction to control the imaging position. ing.

[JP-A 2000-324303]
In (Conventional Example 2), the difference in image forming position due to the difference in wavelength between visible light and infrared light is corrected by changing the thickness of the visible light filter and the infrared light filter. In reality, the image plane formed by infrared light is located farther than the image plane formed by visible light, so in order to correct this difference in image formation position, visible light reading is performed more than infrared light reading. A thick filter is inserted to correct the position of the image plane. By this,
In the case of visible light reading and infrared light reading, it is possible to read an image with one photoelectric conversion element by controlling the optical path lengths to be appropriate. Further, the image forming position can be controlled by moving the image forming lens along the optical axis by the lens moving means.

[JP-A-2001-212195]
In the (conventional example 3), the infrared light cut filter and the visible light cut filter as the optical filters are switched by the filter motor, and at the same time, the image is held integrally by the holding frame and the distance between the optical axes is adjusted in advance. The optical path length of each of the lenses and the line sensor (imaging element) is corrected by the focus motor by the focus motor so that the visible light image and the infrared light image are in the best focus state.

On the other hand, in recent years, with the digitization of electronic / communication technology, a photographic film (so-called “APS film”) having a 240-size transparent magnetic layer has been introduced,
It has become necessary for the image reading apparatus to support various sizes of photographic film, including conventional 135 size photographic film, 110, 120 and 220 size (Brownie size). Therefore, in the image reading apparatus, a zoom lens which can freely set an image frame has been used as an objective lens.

In addition, as a conventional example using the ultraviolet light region as invisible light, as an ultraviolet microscope apparatus capable of inspecting a pattern of a semiconductor integrated circuit, which is becoming finer in recent years, with high resolution and accuracy. In Japanese Patent Laid-Open No. 5-127096 (conventional example 4), light from a light source (mercury lamp) having a wavelength in the visible light region to the near-ultraviolet region is held on a stage through an illumination lens system and an objective lens system. The semiconductor device as the subject is irradiated. The light reflected by the semiconductor device passes through the objective lens again, and is separated by a dichroic mirror into an ultraviolet light path and a visible light path. The separated light passes through the inside of each of the two separated lens barrels, and through the variable power lens system, the ultraviolet rays are CCD for ultraviolet rays (monochrome).
Visible light is directed to the camera and to a color CCD camera. Therefore, the pattern of the semiconductor device, by simultaneously displaying a high-resolution, high-magnification ultraviolet image and a color image that allows the color of the pattern of the semiconductor device to be visually recognized, or by superimposing the ultraviolet image and the color image through an image processing device. By displaying, the ultraviolet image can be displayed as a pseudo color image. Here, in the variable power lens system, the chromatic aberration at the image position and the chromatic aberration at the magnification are corrected with respect to the light in the near ultraviolet region and the visible light region, respectively. Further, a combination of a variable power lens system and an objective lens system can be selected so that the total magnification of the ultraviolet microscope can be changed.

[0010]

However, in the image reading apparatus utilizing infrared light as in the above-mentioned conventional examples 1 to 3, R, G, B filters and IR filters, infrared cut filters, The visible light cut filter etc. is switched by the filter switching motor, and the lens focus is controlled each time, or the focusing lens and the line sensor are integrally held in the holding frame and the distance between the optical axes is adjusted in advance. In the method controlled by, the processing speed is naturally limited because the image is read while sequentially switching the filters, and the filter switching control and the mechanism therefor tend to increase the size and complexity of the apparatus.

Further, in the lens, since the refractive index of the glass used varies depending on the wavelength of light, axial chromatic aberration and chromatic aberration of magnification occur. Especially in a zoom lens, the axial chromatic aberration fluctuates with zooming, and this fluctuation amount poses a problem. Become. It is generally said that the axial chromatic aberration is the largest at the telephoto end. If this axial chromatic aberration remains large, even if tracking (focusing of R, G, and B channels) is accurately adjusted at the wide-angle end, tracking errors of the B and R channels occur at the telephoto end, causing color bleeding. Appears. In recent years, the design of lens optics has become easier with the use of computers, and it can be done precisely and at high speed. Furthermore, the development of glass materials such as crystals of fluorite, which has a different dispersion from ordinary optical glass, and anomalous dispersion glass. Therefore, improvements have been made to such an extent that axial chromatic aberration in the visible light region hardly causes any problem.

However, in a normal zoom lens for photographing, it is difficult to improve axial chromatic aberration in a long wavelength region such as near infrared light or infrared light with respect to a visible light region, and therefore, a photograph of various sizes is taken. When a zoom lens is used in an image reading apparatus to deal with film, the shift of axial chromatic aberration from the wide-angle end to the telephoto end in the long wavelength region due to zooming needs to be corrected by the optical system of the image reading apparatus.

Further, in the ultraviolet microscope apparatus of the prior art example 4, there is a tendency that the apparatus is complicated and the size thereof tends to be large because the dedicated camera is mounted on each of the two separated lens barrels.

In view of the present situation described above, R, G, B filters and I in an image reading device using infrared light and the like.
R filter, infrared cut filter, visible light cut filter, etc. are not used, and axial chromatic aberration can be automatically corrected even if the zoom magnification of the zoom lens changes from the wide-angle end to the telephoto end. (EN) Provided is an image pickup device which is capable of correcting a visible light focal point position and which has, in an ultraviolet microscope device, a compound prism optical system capable of forming one lens barrel and one camera device.

[0015]

Means for Solving the Problems As a result of earnest research in view of the above, the present inventor has solved this problem by the following means. (1) A visible light imaging device and an invisible light imaging device that photoelectrically convert an optical image of a subject formed by an objective lens, and an optical path between the objective lens and both imaging devices. In addition, a first prism having a reflecting surface provided with a coating that transmits a wavelength in the non-visible light region and reflects a wavelength in the visible light region, and a first prism having a surface facing the reflecting surface of the first prism. And a second prism, the imaging device photoelectrically converts an optical image of visible light reflected by the first prism, so that the imaging device for visible light converts an optical image of visible light. An invisible light imaging device for photoelectrically converting an optical image of the invisible light, which is disposed at the image forming position, transmits the first prism, and further transmits the second prism, is an optical device of the invisible light. Placed at the image formation position An image pickup apparatus having a composite prism optical system characterized by comprising Te.

(2) Visible light image pickup device and invisible light image pickup device for photoelectrically converting an optical image of an object formed by an image pickup optical system having a variable image formation magnification, the image pickup optical system and the both image pickups. A first fixed to a prism fixing base, which has a reflecting surface provided with a coating for transmitting a wavelength in the non-visible light region and reflecting a wavelength in the visible light region, disposed in an optical path between the device and the device; A composite prism composed of a prism and a second prism having a surface facing the reflecting surface of the first prism with a constant gap, and the second prism including the reflecting surface of the first prism. A prism driving unit capable of controlling movement along a line and an imaging magnification data memory in which preset imaging magnification data of the imaging optical system is stored, and the imaging device reflects the first prism. Of visible light An optical device for visible light is arranged at a position where an optical image of visible light is formed in order to photoelectrically convert the learned image, and is transmitted through the first prism, and then the optical of non-visible light transmitted through the second prism. An image pickup apparatus having a complex prism optical system, wherein an invisible light image pickup device for photoelectrically converting an image is arranged at an image forming position of an invisible light optical image.

(3) The image forming magnification data is image forming magnification data of the invisible light image corresponding to the image forming magnification of the visible light image at each focal length of the image pickup optical system ( An imaging device having the composite prism optical system according to the item 2).

(4) When the image forming magnification of the image pickup optical system of the second prism changes, the prism driving means is based on the image forming magnification data of the image forming magnification data memory corresponding to the image forming magnification. Is driven so as to move along the reflecting surface of the first prism, and the image pickup device having the composite prism optical system according to item (2) or (3).

(5) The image pickup device further comprises a film defect correction means, and is mounted as an image reading device of a film scanner, (1) to (4). Imaging device having the composite prism optical system of.

(6) The image pickup device further comprises an illumination means for illuminating the subject with a wavelength including wavelengths in the visible light and invisible light areas, or an illumination means for illuminating only the wavelength in the invisible light area, and the same illumination means. An image pickup apparatus having the composite prism optical system according to any one of items (1) to (5), characterized in that the image pickup device includes an illumination control unit for controlling.

[0021]

Embodiments of the present invention will be described in detail with reference to the drawings of the embodiments. Figure 1
FIG. 3 is a block diagram when an image pickup apparatus having a composite prism optical system capable of correcting invisible light focus position of Example 1 of the present invention is used as an image reading apparatus of a film scanner,
2 is an explanatory view of a prism driving mechanism of the embodiment of the present invention, and FIG. 3 is an explanatory view of non-visible light focus position correction of a quadrangular composite prism of the embodiment of the present invention, and FIG.
FIG. 5 is a block diagram when the image pickup apparatus having the compound prism optical system of Example 2 of the invention is used as a surveillance television camera, and FIG. 5 is capable of correcting the invisible light focal position of Example 3 of the invention. FIG. 6 is a schematic diagram when an image pickup device having a compound prism optical system is used as an image pickup device for an ultraviolet microscope device, and FIG. 6 has a compound prism optical system capable of correcting the invisible light focal position of Example 3 of the present invention. FIG. 7 is a block diagram when the image pickup device is used as an image pickup device for an ultraviolet microscope device, and FIG. 7 is an explanatory diagram of invisible light focus position correction of a compound prism other than a quadrangular shape according to the embodiment of the present invention.

[0022]

Embodiment 1 In FIG. 1, light emitted by a light source L having a wavelength in the infrared light region and a wavelength in the visible light region as an illumination light source including a condensing optical system is directed by a film driving device 1 in a constant direction and at a constant speed. After passing through the negative film 2 traveling in the direction, the zoom lens 3 forms an image on the photoelectric conversion element surfaces of the line sensor type image pickup devices 5 and 6 via the compound prism 4.

The composite prism 4 is disposed in the optical path between the zoom lens 3 and the image pickup devices 5 and 6, and has an interference film which transmits wavelengths in the infrared light region and reflects wavelengths in the visible light region. Having a coated surface 4c, the prism fixing base 1
02a (FIG. 2) fixed to the first prism 4a having an isosceles right triangle shape, and the coating surface 4c of the first prism 4a, which face each other through a constant gap, and which can be moved by the prism driving means 16. It is formed in a regular quadrangle shape with the second prism 4b having an isosceles right triangle shape. The second prism 4b can be moved by the prism driving means 16 along the coating surface 4c of the first prism 4a in the direction indicated by the symbol ↔ (FIG. 3). In the composite prism 4, in order to extract only the wavelength in the visible light region or the wavelength in the infrared light region, infrared rays are used as optical filters for cutting extra wavelength regions on the emission surfaces of the two prisms 4a and 4b, respectively. A trimming filter for cutting light, a trimming filter for cutting visible light, or an infrared light specific wavelength (for example, 80
It is preferable to attach a bandpass filter or the like of 0 nm to 850 nm).

A visible light image pickup device 5 is provided for photoelectrically converting an optical image of visible light reflected by the coating surface 4c of the first prism 4a, and the visible light image pickup device 5 is transmitted through the first prism 4a. An infrared light imaging device 6 for photoelectrically converting an optical image of infrared light that has passed through the second prism 4b is provided. As an example of the image pickup device, there is a solid-state image pickup device (CCD) having sensitivity in the visible light region as well as the infrared light region. In addition, this imaging device
It also has the sensitivity of red, green, and blue (R, G, B) light that can read images in color. In this embodiment, as the visible light image pickup device 5, a three-line sensor having three lines (R, G, B) arranged in parallel with a certain interval is used as a light-receiving device. Further, as the infrared light imaging device 6, a one-line imaging device having excellent sensitivity to wavelengths in the infrared light region may be used.

Film 2 traveling in a constant direction and at a constant speed
The photoelectrically converted electric signals (hereinafter referred to as image signals) of the two image pickup devices 5 and 6 that read images line-by-line in synchronism with A / D conversion, automatic gain adjustment,
The signals are amplified by amplifier circuits 7 and 8 having known image processing circuits such as shading correction and gamma correction, and input to the film defect correction means 9. The output images of the amplifier circuits 7 and 8 before the film defect correction are output to terminals 18 and 19,
The output image after the film defect correction can be monitored by connecting a video monitor to the terminal 20.

In the film defect correcting means 9, as described above, dust adhering to the illumination optical system and the imaging optical system, dust on the film, scratches, fingerprints, etc. are read on the image data and black spots (in the case of a positive film). Appear as white dots, etc.,
As a result, an image reproduced by the image reading apparatus becomes a defect, which causes deterioration of the image quality.Therefore, a known technique for automatically making such an image defect invisible or correcting so as to be sufficiently reduced is used. ing. That is, paying attention to the infrared ray transmittance characteristics of the film, only the dust, scratches, fingerprints, etc. that cause the above image quality deterioration are detected by infrared light, and the visible light is detected by the image data of the detected dust, scratches, etc. This is a method of correcting the image data read by. The signal output of the film defect correcting means 9 is supplied via an output terminal 20 to a known photographic printing apparatus having an image memory, an image processing circuit and the like (not shown).

As described above, the film defect is corrected based on the image signals photoelectrically converted from the visible light image pickup device 5 and the infrared light image pickup device 6, but the zoom lens 3 in which the image frame can be freely set. Depending on the size of the film, even if the zoom ratio is changed depending on the film size, an appropriate optical image is formed on the light receiving surface of each image pickup device. In order to correct the position shift of the image plane due to the difference in wavelength,
In the present invention, the optical path length of infrared light can be changed by utilizing the composite prism 4.

In FIG. 1, the zoom lens 3 is provided with a driving means by a small motor (not shown) for each of the iris, focus, and zoom mechanisms as the lens driving means 10, and automatic or manual switching of film size, negative / positive film switching. An iris control means 11, a focus control means 12, each having a manual or automatic control function, based on a command from a control panel 17 having a function such as selection switching.
The lens driving means 10 is driven via the zoom control means 13. Further, for each focal length value in the visible light region from the wide-angle end to the telephoto end of the zoom lens 3, a shift amount of the focal length caused by the wavelength of the infrared light region is measured in advance, and the zoom magnification data obtained by this is obtained. It is stored in the imaging magnification data memory 15. The focal lengths of the zoom lens 3 in the visible light region are preferably based on the center wavelength of the green channel. Further, the center value of the wavelength of the infrared light region takes into consideration the wavelength region in which dust, scratches, etc. can be efficiently detected by the infrared light and the wavelength region in which the infrared light imaging device 6 has a relatively high sensitivity. It is preferable to set.

In accordance with the film size control signal selected by the control panel 17 corresponding to the size of the film 2 loaded in the film drive device 1, the zoom lens 3 is zoomed through the zoom control means 13 and the lens drive means 10. The magnification value (focal length) is controlled to a predetermined value so that an optical image of an appropriate size is formed on the light receiving surface of the visible light imaging device 5, and at the same time, the film size control signal selected by the control panel 17 is selected. Thus, the zoom magnification data by the infrared light corresponding to the predetermined zoom magnification value input to the imaging magnification data memory 15 is read out and added to the prism driving means 16 to drive the second prism 4b. The optical path length of the prism 4 is corrected so that a defect image such as dust or scratches is formed on the light receiving surface of the infrared light imaging device 6.

When a prism having an isosceles right triangle shape is used as the compound prism 4 arranged in the optical path between the zoom lens 3 and the image pickup devices 5 and 6, as shown in FIG.
The first prism 4a is attached to the prism fixing base 102a so that the coating surface 4c thereof is inclined by 45 degrees with respect to the optical axis 42 (see FIG. 3), and the prism fixing base 102a is attached to the prism. It is fixed to the plate 101. Further, the second prism 4b is attached to the prism fixing base 102b so as to face the coating surface 4c of the first prism 4a via a constant gap of several tens of microns, and the ⇔ mark (Fig. It is attached to the prism mounting plate 101 so as to be movable in the direction indicated by 3). The prism fixing base 102b is driven by a prism driving mechanism 104 having a motor 103 as a power source. The motor 103 is controlled and driven by a drive signal sent from the imaging magnification data memory 15 via the control cable 105.

The optical path length correcting means will be described with reference to FIG. For example, a coin below the surface of the water appears to float. This indicates that the apparent length becomes shorter in a medium having a high refractive index. When the coin depth is d and the refractive index of water is n, the apparent coin depth is apparent depth = d / n. The same applies to the case of a glass block. A glass block having a thickness d and a refractive index n is d / n when converted into air.
It becomes the thickness of. Therefore, when the glass block having the thickness d is inserted in the optical path, the optical path length is extended by (1-1 / n) × d. That is, the optical path length can be controlled by changing the thickness d of the glass block.

In FIG. 3, visible light reflected by the coating surface 4c that transmits wavelengths in the infrared light region and reflects wavelengths in the visible light region and is refracted forms an image on the light receiving surface of the visible light imaging device 5. . On the other hand, light having a wavelength in the infrared light region passes through the coating surface 4c of the first prism 4a, and further the second prism 4a.
An image is formed on the light-receiving surface 6b of the infrared light imaging device after passing through b. Assuming that the zoom magnification (focal length) position of the zoom lens 3 is constant, the second prism 4b moves along the film surface 4c in the direction indicated by ↔ and reaches the position of 4bx indicated by the alternate long and short dash line. Then, the glass thickness of the compound prism 4 in the direction of the optical axis 42 becomes thin, and the image forming point moves to 6x shown by the chain line. Further, when the second prism 4b moves in the direction indicated by the mark ⇔ along the coating surface 4c and reaches the position 4by shown by the dotted line, the optical axis 42 of the compound prism 4 is reached.
The glass thickness in the direction becomes thicker, and the image formation point is indicated by the dotted line.
Move to y.

The above description has been made in the case where the zoom magnification of the zoom lens 3 is a constant value for easy understanding of the principle.
Actually, as described above, the axial chromatic aberration from the wide-angle end to the telephoto end changes in the long wavelength region (infrared light region) due to zooming, and the imaging point moves, so the movement of the imaging point is tracked automatically. In the present invention, the optical path length of the infrared light can be controlled by using the compound prism 4 so that it can be corrected.

Although the line sensor type image pickup device is used as an example, the film 2 is stopped at the image pickup position,
A method of capturing an image using an area sensor type imaging device may be used. Although the infrared light imaging device 6 is described as being arranged at the optical image forming position, it may be arranged in advance at a position slightly deviated from the optical image forming position depending on the known film defect correction method. You may set it up.

The composite prism 4 of the first embodiment is formed into an isosceles right triangle for ease of processing the prism. However, due to restrictions on the arrangement of the composite prism 4 and the image pickup devices 5 and 6 of the image pickup device 14, etc. The composite prism 4 ′ may be configured as shown in FIG. 7 by combining two prisms having different shapes. In particular, the first prism 4'a has a wedge-like shape like the prism for the blue channel of the R, G, B3 plate prism optical system for television cameras, and the coating of the first prism 4'a. The optical image of the visible light reflected by the surface 4'c is totally reflected on the incident surface side, and then the optical image is formed on the visible light imaging device 5. The glass thickness at the optical axis center of the second prism 4'b may be substantially the same as the optical path length from the coating surface 4'c to the exit surface of the first prism 4'a. With such a configuration, although the shape of the composite prism 4 ′ becomes complicated, it is possible to prevent the first prism 4′a from reversing the image horizontally (or vertically). Other configurations and operations are similar to those described with reference to FIG.

[0036]

[Embodiment 2] FIG. 4 is a block diagram in the case where an image pickup apparatus having a square-shaped composite prism optical system is used as a surveillance television camera. For example, an area sensor type image pickup device is used. It is suitable when applied to a day / night surveillance camera that uses infrared light illumination at nighttime, or a camera for monitoring an object that emits infrared light.

In FIG. 4, the image processing means 21 capable of manually or automatically switching the output signals of the amplifier circuits 7 and 8 and the illumination control means 23 capable of on / off control of the infrared light illumination lamp IRL are provided for a subject (not shown). Image processing means 2 by detecting a sensor output for detecting brightness or a video level
It is also possible to automatically or manually control the image switching of No. 1 and the blinking of the infrared light illumination lamp IRL. If a video monitor for monitoring is connected to the output terminals 18, 19 and 22, each image can be monitored. In this embodiment,
Since a case where a fixed focus lens is used as the objective lens 3'for monitoring is shown, the composite prism 4 is
The prism 4a and the second prism 4b are adhered and fixed, and the image pickup devices 5 and 6 are fixed to the presumed image forming positions. Therefore, the imaging magnification data memory 15, the prism driving means 16 and the like shown in the first embodiment are not used, and the entire apparatus is simplified. Of course, a zoom lens is used as the objective lens 3 ', and the composite prism 4 optical system capable of correcting the invisible light focus position, the imaging magnification data memory 15, the prism driving means 16 and the like are mounted, and the same as in the first embodiment. You may expect the action and effect. Other configurations and operations are similar to those of the first embodiment.

[0038]

Third Embodiment This embodiment shows a case where the image pickup device 14 having a complex prism optical system capable of correcting the invisible light focal position is used as a camera for an ultraviolet microscope device. In FIG. 5, an ultraviolet microscope device 39 supports a lens barrel 26 on a lens base 24 via an arm 25, and an image pickup device 14 not including an objective lens such as a zoom lens is mounted on the lens barrel 26 via a turret 40. ing. Also, when observing at high magnification,
For example, a mechanical stage 38 capable of smoothly moving a semiconductor device 36 which is a subject is attached to the arm 25,
The mechanical stage 38 includes a Z stage 38Z, an X stage 38X attached to the Z stage 38Z, and a Y stage 38Y (not shown).
Adjust screw 37 so that the relative position of semiconductor device 36 and objective lens system 29 can be changed for focusing.
By operating Z, the optical axis of the objective lens system 29 (Z
You can make a small movement along the axis. Furthermore, X stage 3
The 8X and Y stage 38Y are respectively adjusted by operating the adjusting screw 37X and an adjusting screw 37Y (not shown).
It can be slightly moved in the vertical direction to the stage 38Z. Then, in order to mechanically prevent the vibration transmitted from the floor, the mirror base 2
It is preferable that the vibration isolation table 41 is installed in the lower part of 4.

Light from a light source 27, such as a mercury lamp, a xenon lamp, or a mercury / xenon lamp, which emits light having a wavelength of visible to near-ultraviolet is appropriately converged by an illumination lens system 28 and reflected by a half mirror 32. , Revolver 30
Objective lens system 2 consisting of multiple lenses attached to the
9 is focused by the subject, for example, the semiconductor device 3
It is incident on 6. The light reflected from the semiconductor device 36 again passes through the objective lens system 29, the half mirror 32, the imaging lens system 31, and the half mirror 33, and the magnifying lens system 34 including a plurality of lenses housed in the turret 40.
An image is formed on the area sensor type image pickup device of the image pickup device 14 having the complex prism optical system capable of correcting the invisible light focal position according to the present invention. On the other hand, the light reflected by the half mirror 33 can be visually observed by the eyepiece system 35 lens.

Here, for example, a lens having a magnification of 10, 50, 100 is attached to the revolver 30 in the objective lens system 29,
As a magnifying lens system 34 on the turret 40, magnifications 1, 2,
By mounting and combining 4 lenses, 10,
Seven types of total imaging magnifications of 20, 40, 50, 100, 200, and 400 times can be obtained, and the pattern of the semiconductor device 36 can be observed by switching from low magnification to high magnification. However, with the change of these total imaging magnification,
Similar to the case of changing the zoom magnification of the zoom lens described above, axial chromatic aberration occurs in the visible light region in the wavelength region of invisible light, and it is necessary to correct this.

Therefore, the correction of the axial chromatic aberration caused by the combination of the objective lens system 29 and the magnifying lens system 34 will be described with reference to FIG. UV microscope device 3
Reference numeral 9 is a revolver (30) to which an objective lens system 29 is attached.
And a turret (40) fitted with a magnifying lens system 34
, A control panel 52 for selecting and controlling each lens via the lens drive means 51, the objective lens system 29 and the magnifying lens system 3 selected by the control panel 52.
The prism driving means 16 is provided for reading the image formation magnification data from the image formation magnification data memory 53 based on the total image formation magnification value of the combination of 4 and driving the second prism 4b of the compound prism 4. The image forming magnification data is obtained for each total image forming magnification by the combination of the objective lens system 29 and the magnifying lens system 34 by the wavelength in the ultraviolet light region for each total image forming magnification value (focal length) in the visible light region. The amount of deviation of the imaging magnification that occurs is measured in advance, and the imaging magnification data thus obtained is stored in the imaging magnification data memory 53.

When an arbitrary combination of the objective lens system 29 and the magnifying lens system 34 is selected on the control panel 52, the revolver 30 and the turret 4 are driven by the lens driving means 51.
0 to drive a designated objective lens system 29 and magnifying lens system 34
At the same time, predetermined imaging magnification data is read from the imaging magnification data memory 53, the second prism 4b is driven via the prism driving means 16, and the optical path length of the prism 4 is corrected.

The subject image whose axial chromatic aberration has been corrected is output to the output terminal 19 as a color image for confirming the color of the semiconductor device (36) which is formed on the visible light image pickup device 5 and photoelectrically converted. It is output to the output terminal 18 as a high-resolution, high-magnification ultraviolet image of the semiconductor device (36) which is image-formed and photoelectrically converted on the optical imaging device 6. Also,
By superimposing and displaying the ultraviolet image and the color image by the image processing means 21, the ultraviolet image can be output from the output terminal 22 as a pseudo color image and displayed on a video monitor (not shown).

In the above description, "... lens system"
Means a system containing one or more optical lenses.
The "eyepiece system" means a system including an eye lens, a field lens, etc. for observing with the naked eye. here,
The half mirror 33 is a total reflection mirror, and in order to efficiently supply the total reflection light from the semiconductor device 36 to the image pickup apparatus 14, one of the upper and lower ends is provided with a rotating elbow, and when observing with the eyepiece system 35, FIG. The total reflection light from the semiconductor device 36 may be supplied to the eyepiece system 35 at the position shown by and the total reflection mirror may be deviated from the optical path by using a hinge when observing with the imaging device 14. Further, when observing and measuring a subject that is weak against ultraviolet rays, a mechanical shutter (not shown) is provided in any one of the optical paths of the illumination lens system 28, and the ultraviolet rays to the subject are exposed without turning on / off the light source 27. Irradiation may be prevented and damage to the subject may be minimized. Other configurations and operations are similar to those of the first embodiment.

[0045]

According to the present invention, the following effects are exhibited. 1. An imaging device for visible light and an imaging device for invisible light that photoelectrically converts an optical image of a subject formed by an objective lens, and an invisible light arranged in an optical path between the objective lens and both imaging devices. A first prism having a reflecting surface provided with a coating that transmits wavelengths in the region and reflects wavelengths in the visible light region; and a second prism having a surface facing the reflecting surface of the first prism. Since the composite prism having the structure is provided, it is possible to simultaneously capture both a visible light image and an invisible light image with one imaging device, and it is possible to reduce the size and cost of the device.

2. An imaging device for visible light and an imaging device for invisible light, which photoelectrically converts an optical image of a subject formed by an imaging optical system having a variable imaging magnification, and an optical path between the imaging optical system and the imaging devices. Placed inside,
A first prism fixed to a prism fixing base, the first prism having a reflecting surface having a coating that transmits a wavelength in the non-visible light region and reflecting a wavelength in the visible light region; and the reflecting surface of the first prism. A composite prism composed of a second prism having surfaces facing each other with a constant gap, prism driving means capable of controlling movement of the second prism along the reflecting surface of the first prism, Since the image forming magnification data memory in which the set image forming magnification data of the image pickup optical system is stored is provided, for example, the zoom magnification of the zoom lens,
Alternatively, the axial chromatic aberration in the invisible light region caused by changing the image forming magnification of the imaging optical system whose image forming magnification is variable, such as the total image forming magnification by the combination of the objective lens and the magnifying lens of the microscope device, is corrected by two prisms. By controlling the glass thickness in the direction of the optical axis of the compound prism that combines the two types, it is possible to continuously and automatically correct, and obtain the appropriate optical image of the visible light region and the invisible light region, the light receiving surface of each imaging device. At the same time, it is possible to reduce the size and cost of the imaging device.

3. Without using R, G, B filters and IR filters, infrared cut filters, visible light cut filters, etc., a composite prism separates the wavelengths of the visible light region and the invisible light region to provide a visible light imaging device. Since images of each wavelength region are simultaneously obtained by the invisible light imaging device, if used as an image reading device such as a film scanner, the processing speed is high, and the device is downsized, simplified, and inexpensive. Can be easily achieved.

4. Since the prism is arranged in the optical path between the image pickup optical system and the image pickup device, it is possible to reduce the size of the prism and the size of the apparatus.

[0049]

[Brief description of drawings]

FIG. 1 is a block diagram when an image pickup apparatus having a compound prism optical system capable of correcting invisible light focus position according to the first embodiment of the present invention is used as an image reading apparatus of a film scanner.

FIG. 2 is an explanatory view of a prism driving mechanism according to the embodiment of the invention.

FIG. 3 is an explanatory diagram of invisible light focus position correction of a quadrangular composite prism of the embodiment of the invention.

FIG. 4 is a block diagram when the image pickup apparatus having the compound prism optical system according to the second embodiment of the present invention is used as a surveillance television camera.

FIG. 5 is a schematic diagram when an image pickup apparatus having a compound prism optical system capable of correcting the invisible light focus position according to the third embodiment of the present invention is used as an image pickup apparatus for an ultraviolet microscope apparatus.

FIG. 6 is a block diagram when an image pickup apparatus having a compound prism optical system capable of correcting the invisible light focus position according to the third embodiment of the present invention is used as an image pickup apparatus for an ultraviolet microscope apparatus.

FIG. 7 is an explanatory diagram of invisible light focus position correction of a compound prism other than a square shape according to the embodiment of the present invention.

[Explanation of symbols]

1: Film drive device 2: Film 3: Zoom lens 3 ': Objective lens 4, 4': Composite prism 4a, 4'a:
1st prism 4b, 4'b: 2nd prism 4bx, 4by, 4'bx, 4'by: 2nd prism moving position 4c, 4'c: coating surface 5,6: imaging device 6b, 6x , 6y: Imaging point 7, 8: Amplifying circuit 9: Film defect correcting means 10: Lens driving means 11: Iris control means 12: Focus control means 13: Zoom control means 14: Imaging device 15: Imaging magnification data memory 16 : Prism driving means 17: Control panel 18, 19, 2
0, 22: output terminal 21: image processing means 23: illumination control means 24: mirror base 25: arm 26: lens barrel 27: light source 28: illumination lens system 29: objective lens system 30: revolver 31: imaging lens system 32 , 33: Half mirror 34: Magnifying lens system 35: Eyepiece system 36: Semiconductor device 37X, 37Z: Adjusting screw 38: Mechanical stage 38X: X stage 38Z: Z stage 39: Ultraviolet microscope device 40: Turret 41: Vibration isolation table 42: optical axis 51: lens driving means 52: control panel 53: imaging magnification data memory L: light source IRL: infrared light illumination lamp 101: prism mounting plate 102a, 10
2b: prism fixing base 103: motor 104: prism driving mechanism 105: control cable

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 31/04 H04N 5/225 D 5C072 H04N 1/19 1/04 102 5F051 5/225 H01L 31/04 Q (72) Inventor Takami Hasegawa 1-18-2 Shirayama, Midori-ku, Yokohama-shi, Kanagawa German Industry Center J-AI Corporation F-Terms in JAI Corporation (Reference) 2H042 CA07 CA12 CA17 2H052 AB24 AB29 AC04 AC12 AD06 AF02 AF14 2H087 KA03 MA00 NA03 RA41 RA44 TA01 TA03 5B047 AA05 BB01 BC04 BC07 5C022 AA01 AA15 AC42 AC51 5C072 AA01 DA10 DA21 VA03 5F051 BA05 JA02 JA20

Claims (6)

[Claims] 1. A visible light imaging device and an invisible light imaging device for photoelectrically converting an optical image of an object formed by an objective lens, and an optical path between the objective lens and the both imaging devices. A first prism having a reflection surface provided with a coating that transmits a wavelength in the non-visible light region and reflects a wavelength in the visible light region, and a surface of the first prism facing the reflection surface. And a second prism having a composite prism, wherein the imaging device photoelectrically converts an optical image of visible light reflected by the first prism, and the imaging device for visible light is an optical device for visible light. It is arranged at an image forming position and passes through the first prism,
Further, an invisible light image pickup device for photoelectrically converting an invisible light optical image that has passed through the second prism is arranged at an image formation position of the invisible light optical image. An imaging device having an optical system. 2. An image pickup device for visible light and an image pickup device for invisible light, which photoelectrically converts an optical image of a subject formed by an image pickup optical system having a variable image forming magnification, the image pickup optical system, and both image pickup devices. A first prism fixed to a prism fixing base having a reflecting surface provided with a coating for transmitting a wavelength in the non-visible light region and reflecting a wavelength in the visible light region, the first prism being disposed in an optical path between And a second prism having a second prism having a surface facing the reflection surface of the first prism with a constant gap, and the second prism on the reflection surface of the first prism. The image pickup device is provided with a prism driving unit that can be controlled to move along the image pickup device, and an image formation magnification data memory in which preset image formation magnification data of the image pickup optical system is stored, and the image pickup device is reflected by the first prism. Optical image of visible light An image pickup device for visible light is disposed at the position where an optical image of visible light is formed in order to photoelectrically convert the optical image of the invisible light transmitted through the first prism and further transmitted through the second prism. An image pickup apparatus having a composite prism optical system, wherein an invisible light image pickup device for photoelectric conversion is arranged at an image forming position of an invisible light optical image. 3. The image forming magnification data is image forming magnification data of a non-visible light image corresponding to an image forming magnification of a visible light image at each focal length of the image pickup optical system. An imaging device having the composite prism optical system according to item 2. 4. When the image forming magnification of the image pickup optical system changes, the second prism is driven by the prism driving means based on image forming magnification data of the image forming magnification data memory corresponding to the image forming magnification. The image pickup device having the composite prism optical system according to claim 2, wherein the image pickup device is driven so as to move along the reflection surface of the first prism. 5. The composite prism optics according to claim 1, wherein the image pickup device further comprises a film defect correction means, and is mounted as an image reading device of a film scanner. Imaging device having a system. 6. The illuminating means for illuminating an object with a wavelength including a wavelength of visible light and a wavelength of an invisible light area, or an illuminating means for illuminating an object with only a wavelength of an invisible light area, and controlling the illuminating means. 6. An image pickup apparatus having the complex prism optical system according to claim 1, further comprising: