JPH10227982A - Optical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a mirror surface error and a tracking error by rotating and moving a mirror surface inspection part and a tracking part on the optical axis of light to be observed and distributing the light of a light source to the mirror surface inspection part and tracking part. SOLUTION: A mirror surface inspecting device and a tracking device part of an optical device 30 have a pickup mirror 31, a dichroic mirror 32 as a wavelength splitting optical element, the mirror surface inspection part 22, and the tracking part 24 inside. The dichroic mirror 32 transmits or reflects light selectively according to the wavelength while maintaining the intensity of the incident light. The dichroic mirror 32 reflects light of a long wavelength band and makes it incident on the mirror surface inspection part 22, and transmits light of a short-wavelength band and makes it incident on the tracking part 24 to make the light of one light source incident on the mirror surface inspection part 22 and tracking part 24. Further, a rotary driving device 33 for the mirror surface inspecting device and tracking device part is rotated and moved on the optical axis 9 as an axis of rotation and a radial movement device 34 is moved at right angles to the optical axis 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to miniaturization of a mirror inspection device and a tracking device for improving observation accuracy of an optical device such as an optical infrared telescope device and improvement of observation accuracy of the optical device. .

[0002]

2. Description of the Related Art FIG. 5 is a perspective view showing a general reflection type large-diameter optical infrared telescope apparatus. FIG. 6 is a diagram schematically showing an optical system of the optical infrared telescope device shown in FIG. 5 together with an optical axis. 7 (a) and 7 (b) are diagrams schematically showing the configurations of a mirror inspection device and a tracking device of an optical infrared telescope device, respectively, and FIG. 8 is a drive device for these devices and its installation. It is a figure which shows a position schematically.

As shown in FIG. 5, a gantry 2 of an optical infrared telescope apparatus 1 is supported on an AZ (azimuth) shaft 3 so as to be rotatable around a vertical axis, and thereby the optical infrared telescope apparatus 1 is mounted on a vertical axis. Can be rotated around. A lens barrel 4, which is a main part of the optical infrared telescope device 1, is rotatably supported on the gantry 2 by an EL (Elevation) shaft 5 so as to be rotatable from the zenith direction to the horizontal direction. The lens barrel 4 is provided with a main reflecting mirror 6 and a sub-reflecting mirror 7. As shown in FIG. 6, the main reflecting mirror 6 is supported by a mirror driving device 8, and the mirror driving device 8
By changing the mirror surface shape of the main reflecting mirror 6, the spread of the image formed by the main reflecting mirror 6 and the sub-reflecting mirror 7 can be adjusted. Reference numeral 9 shown in the figure is the optical axis of the lens barrel 4.

As shown in FIG. 6, a main reflecting mirror 6 is a concave mirror having a hole 6a in the center, and a sub-reflecting mirror 7 is a convex mirror. In such an optical infrared telescope apparatus 1, the light of the celestial body 10 to be observed is condensed via the main reflecting mirror 6 and the sub-reflecting mirror 7 in the lens barrel 4, and the hole 6 a of the main reflecting mirror 6 is formed.
Through the focal point 11.

However, when deformation or displacement occurs in the lens barrel 4, the main reflecting mirror 6, or the like, a mirror surface error or a tracking error that hinders observation of the celestial body 10 occurs. The light of the celestial body 10 reflected by the main reflecting mirror 6 and the sub-reflecting mirror 7 toward the focal point 11 contains signals of a mirror surface error and a tracking error. The mirror inspection device 12 and the tracking device 13 disposed in the vicinity of the focal point 11 use the celestial bodies 14 and 15 in the same field of view of the astronomical object 10 and the optical infrared telescope apparatus 1, respectively. This is a device for detecting a mirror error and a tracking error caused by the fluctuation of the cylinder 4. When the main reflecting mirror 6 is distorted, the image of the celestial body 10 is blurred and spread, and the lens barrel 4
When the image fluctuates, the image of the celestial body 10 to be observed in the field of view is shaken without being determined. Further, the celestial body 14 and the celestial body 15 required for detecting the mirror surface error and the tracking error need to have sufficient brightness (brightness of about 12 to 13th magnitude star). Whether to use as 15 differs depending on the direction in which the optical infrared telescope apparatus 1 is directed and the time.

As shown in FIGS. 7 (a), 7 (b) and 8, a mirror inspection device 12 and a tracking device 13 are a rotary driving device for rotating these devices around the optical axis 9. 16 and 17 and one radial moving device 18 and 19 for moving these devices in a direction perpendicular to the optical axis 9. Rotary drive 16, 17
The radial drive devices 18 and 19 are driven through respective control devices 20a to 20d. With such a configuration, the mirror inspection device 12 and the tracking device 1
The mirror inspection device 12 and the tracking device 13 take in the light of the celestial body 14 and the celestial body 15, respectively, by freely moving the respective installation positions of the three in a plane around the optical axis 9 and perpendicular to the optical axis 9. Can be. Hereinafter, each of the mirror inspection device 12 and the tracking device 13 will be described.

[0007] As shown in FIG.
2 includes a pickup mirror 21 and a mirror inspection unit 22. The mirror inspection unit 22 includes a reference light source, a CCD array, and an optical path (both not shown) for optically connecting these. The CCD camera is connected to an image analyzer (not shown). The mirror inspection unit 22 having such a structure converts the respective images of the celestial body 14 and the light of the reference light source into C
By performing comparison on the CD array, distortion (mirror surface error) of the main reflecting mirror 6 is detected. The reference light source is installed in the mirror surface inspection unit 22 so that the same image as the image on the CCD array due to the light passing through the optical system of the optical infrared telescope apparatus 1 is projected on the CCD array when there is no mirror error. Light source.

Therefore, when the main reflecting mirror 6 is distorted, that is, when the image of the celestial object 10 to be observed is blurred and spread, the image of the celestial object 14 and the light of the reference light source are displayed on the CCD array. Since the difference in the shape of the image occurs, the mirror inspection unit 22 can detect a mirror error. When a mirror error occurs as described above, a control device (not shown) drives the mirror driving device 8 based on the mirror error signal from the mirror inspection unit 22, and the distortion of the main reflecting mirror 6 is corrected.

On the other hand, as shown in FIG. 7B, the tracking device 13 includes a pickup mirror 23 and a tracking unit 24. The tracking unit 24 includes an optical path including a convex lens and C
Built-in CD camera (both not shown). In addition, CCD
The camera is connected to an image analyzer (not shown). The tracking unit 24 having such a structure captures an image of the celestial body 15 on the CCD camera and shakes the image of the celestial body 10 in the field of view (tracking error) due to fluctuation of the lens barrel 4 due to disturbance such as wind. A tracking error for driving the driving device (not shown) to slightly rotate the optical infrared telescope 1 around the AZ axis 2 and the EL axis 4 so as to prevent the image of the celestial body 10 from moving in the field of view. This is to detect a signal.

Therefore, when the image of the celestial body 10 in the field of view of the telescope apparatus is fluctuating, the celestial body 15 on the CCD camera
, The image analyzer connected to the CCD camera in the tracking unit 24 detects a tracking error based on the shake. The tracking unit 24 transmits the tracking error detected by the image analyzer as a tracking error signal to the driving devices of the AZ axis 2 and the EL axis 4, and the driving device adjusts the AZ axis 2 and the EL axis 4, so that the astronomical object is adjusted. The shake of the ten images is suppressed.

By providing the mirror inspection device 12 and the tracking device 13 having the above-described mirror inspection unit 22 and tracking unit 24 therein, the astronomical object
Observations.

[0012]

However, as described above, the celestial bodies 14 and 15 required for detecting the mirror surface error and the tracking error require a certain level of brightness, but actually, In many cases, there are no two celestial bodies having sufficient brightness in the same field of view as the celestial body 10. For this reason, the mirror surface error and the tracking error are detected in a state where the luminosity of either the celestial body 14 or 15 is insufficient. As a result, the detected errors become large, and the optical performance of the optical infrared telescope device 1 is reduced. There was a problem of inviting. In addition, since the mirror inspection device 12 including the mirror inspection unit 22 and the tracking device 13 including the tracking unit 24 are separate units, each of these devices requires an optical system, a support unit, a driving device, and the like. However, there is a problem that it is difficult to secure a sufficient space for installing the mirror inspection device 12 and the tracking device 13 near the focal point 11 where various devices are densely packed.

Therefore, an object of the present invention is to reduce the mirror error and the tracking error even in a situation where there is only one celestial object having a certain level of brightness or more in the same field of view as the celestial object to be observed. An object of the present invention is to provide an optical device that maintains high optical performance of an optical device such as an infrared telescope device and that can be easily installed near a focal point where it is difficult to secure a sufficient space.

[0014]

The optical device according to the present invention comprises:
A mirror inspection unit that detects distortion of a mirror surface of the optical system based on light from a light source that has passed through the optical system, a tracking unit for tracking a light source to be observed, and a mirror inspection unit and a tracking unit for tracking the light source to be observed. A rotation direction driving device for rotating the optical axis of light as a rotation axis, a radial driving device for moving the mirror inspection unit and the tracking unit in a direction perpendicular to the optical axis of the light to be observed, and an optical device. Split optical means for distributing the light of the light source through the system to the mirror inspection unit and the tracking unit.

The splitting optical means is a wavelength splitting optical element for splitting light by wavelength.

The splitting optical means is a light splitting optical element for splitting light according to the polarization direction.

Further, the split optical means includes a time-division optical path switching optical mechanism for switching the optical path by time-division of the light.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. FIG. 1 is a diagram schematically showing a cross section of a mirror inspection device and a tracking device of an optical device according to Embodiment 1 of the present invention. FIG. 2 is a diagram schematically showing a mirror inspection device and a tracking device of the optical device shown in FIG. 1 together with the optical axis of the lens barrel.

In FIG. 1, for example, a mirror inspection device and a tracking device portion of an optical device 30 which is an optical infrared telescope device include a pickup mirror 31, a dichroic mirror 32 which is a wavelength division optical element as a division optical unit, a mirror inspection unit 22, The tracking unit 24 is built in. The dichroic mirror 32 is a mirror that can selectively transmit or reflect light according to the wavelength while maintaining the intensity of the incident light. The dichroic mirror 32 is
The dichroic mirror 32 is set so that the light in the long wavelength band is reflected and made incident on the specular inspection unit 22, and the light in the short wavelength band is transmitted and made incident on the tracking unit 24. (1) Light from one light source can be made incident on the mirror inspection unit 22 and the tracking unit 24.

As shown in FIG. 2, a mirror inspection device and a tracking device of the optical device 30 are provided with a rotation driving device 33 for rotating the optical axis 9 as a rotation axis and a direction perpendicular to the optical axis 9. Moving device 3 for moving to
4 is provided. The rotation drive device 33 and the radial drive device 34 are driven through control devices 35a and 35b. With such a configuration, the positions of the mirror inspection device and the tracking device of the optical device 30 can be freely moved in a plane around the optical axis 9 and perpendicular to the optical axis 9. The light of the celestial body 36 can be taken into the inspection device and the tracking device.

The mirror inspection unit 22 incorporates a reference light source, a CCD array, and an optical path (not shown) for optically connecting the reference light source and the CCD array. By comparison, distortion (mirror surface error) of the main reflecting mirror 6 (see FIG. 5) is detected. The reference light source is a light source installed in the mirror inspection unit 22 so that the same image as the image formed on the CCD array by the incident light when there is no mirror error is displayed on the CCD array.

Therefore, when the main reflecting mirror 6 is distorted, that is, when the image of the celestial object 10 to be observed is not determined, the image of the celestial object 36 and the light image of the reference light source on the CCD array are shifted. Therefore, the mirror inspection unit 22 detects a mirror error. When the detected mirror surface error signal is transmitted to the control device (not shown) of the mirror surface driving device 8, the control device (not shown) drives the mirror surface driving device 8 based on the mirror surface error signal, thereby The distortion of the reflecting mirror 6 is corrected.

The tracking unit 24 incorporates an optical path including a convex lens and a CCD camera (both not shown).
The CCD camera is connected to an image analyzer (not shown). The tracking unit 24 having such a structure captures an image of the celestial body 36 on a CCD camera and uses the lens barrel 4 due to disturbance such as wind.
As a result, the driving device (not shown) is driven so as to prevent the image of the celestial body 10 from being shaken in the field of view, and the optical infrared telescope 1 is slightly rotated around the AZ axis 2 and the EL axis 4 so that the celestial object 10 is rotated. A tracking error signal required for control for preventing the image from being shaken in the visual field is detected.

Accordingly, when the image of the celestial body 10 in the field of view of the optical infrared telescope apparatus is fluctuating, the image of the celestial body 36 on the CCD camera fluctuates.
An image analyzer connected to the camera detects a tracking error. Then, the tracking unit 24 converts the tracking error signal into the AZ axis 2 and the EL signal.
The vibration is transmitted to the driving device of the axis 4, and the driving device adjusts the AZ axis 2 and the EL axis 4, thereby suppressing the image shake of the celestial body 10 in the field of view.

As described above, the mirror inspection unit and the tracking unit of the optical device 30 according to the present invention can be used as the mirror inspection unit 2 without reducing the light intensity of one light source (celestial body 36).
By using the dichroic mirror 32, which is a division optical means distributed to the tracking unit 2 and the tracking unit 24, the light of one celestial body having sufficient brightness can be transmitted to the mirror inspection unit 22 and the tracking unit without attenuating the light intensity. 24. As a result, even in a situation where there is only one celestial object having a certain level of brightness or more within the same field of view as the celestial object to be observed, the mirror surface error and the tracking error can be reduced, and the optical performance of the optical infrared telescope apparatus is reduced. improves.

The mirror inspection unit and the tracking unit of the optical device 30 include the mirror inspection unit 22 and the tracking unit 24 in one.
Since these devices are housed in one unit, these devices are rotated and moved around the optical axis 9 by one rotation driving device 33 and one radial movement device 34,
It can be moved in a direction perpendicular to the optical axis 9. Therefore, it is possible to easily install the mirror inspection device and the tracking device of the optical device 30 near the focal point where it is difficult to secure a sufficient space.

In the first embodiment, the long wavelength band is adjusted by the dichroic mirror 32 to the mirror inspection unit 22.
The short wavelength band is set so as to be distributed to the tracking unit 24. On the contrary, the short wavelength band is set to the mirror inspection unit 22.
In addition, the same effect can be obtained even if the setting is made so that the long wavelength band is distributed to the tracking unit 24.

Embodiment 2 FIG. 3 is a sectional view schematically showing a mirror inspection device and a tracking device of an optical device according to Embodiment 2 of the present invention. In the second embodiment, the mirror inspection device and the tracking device portion of the optical device 40 include a polarizing plate 4 as a light splitting optical element as a splitting optical unit.
Embodiment 1 is the same as Embodiment 1 except for using 1.

As shown in FIG. 3, the polarizing plate 41 is an element for dividing incident light into S-polarized light and P-polarized light. The S-polarized light enters the mirror inspection unit 22, and the P-polarized light enters the tracking unit 24. Hereinafter, similarly to the first embodiment, the mirror error by the mirror inspection unit 22 and the tracking error by the tracking unit 24 are detected, the distortion of the main reflecting mirror 6 is corrected, and the astronomical object 1 in the field of view is corrected.
The image of 0 is kept constant.

The intensity of the S-polarized light and the intensity of the P-polarized light split by the polarizing plate 41 are each half of the intensity of the incident light, but an astronomical object having sufficient brightness within the field of view of the optical infrared telescope apparatus. The probability of finding one is high,
This is not a major observational problem.

The mirror inspection device and the tracking device of the optical device 40 use a polarizing plate 41, which is a split optical means for distributing light according to the polarization direction, so that the light of one celestial object can be reflected by the mirror inspection device 22 and the tracking device 24. Can be incident. Therefore, similarly to the case of Embodiment 1, even in a situation where there is only one celestial object having a certain degree of brightness or more within the same field of view as the celestial object to be observed, it is possible to reduce the mirror error and the tracking error to a small value. The optical performance of the optical infrared telescope device can be improved. Also, since the mirror inspection unit 22 and the tracking unit 24 are housed in one unit, one rotation driving device 33 and 1
By means of two radial movement devices 34, these devices are
Can be rotated about the axis of rotation, and can be moved in a direction perpendicular to the optical axis 9. Therefore, the optical device 40 is located near the focal point where it is difficult to secure a sufficient space.
The mirror inspection device and the tracking device can be easily installed.

Embodiment 3 FIG. FIG. 4 is a sectional view schematically showing a mirror inspection device and a tracking device of an optical device according to Embodiment 3 of the present invention. In the third embodiment, the mirror inspection device and the tracking device of the optical device 50 conform to the first embodiment, except that the time division optical path switching optical mechanism 51 is used as the division optical unit.

The time-division optical path switching optical mechanism 51 includes a driving device 52 and a pickup mirror 53 for switching the optical path in a time-division manner. The driving device 52 is
A control device for switching the optical path in a time-division manner is built in.
In FIG. 4, when the pickup mirror 53 is at the position indicated by the solid line, all light incident on the mirror inspection device and the tracking device of the optical device 50 is incident on the mirror inspection unit 22, and the pickup mirror 53 is positioned at the position indicated by the dotted line. , All the incident light enters the tracking unit 24.

In order for the specular inspection unit 22 to detect a mirror error, it is necessary to cause light to enter the specular inspection unit 22 for about 10 seconds every minute. On the other hand, in order for the tracking unit to detect a tracking error, it is necessary to continuously input light. Therefore, the driving device 52 is operated for 10 minutes per minute.
For a second, the pickup mirror 53 is installed at the position shown by the solid line in FIG.
For the remaining 50 seconds, the pickup mirror 53 is set at the position shown by the dotted line in FIG.

The mirror inspection device and the tracking device portion of the optical device 50 use a time-division optical path switching optical mechanism 51 for time-divisionally switching the light and switching the optical path, so that the light of one celestial object is reflected by the mirror inspection unit 22 and The light can enter the tracking unit 24 in a time-division manner. Therefore, similarly to the case of Embodiment 1, even in a situation where there is only one celestial object having a certain degree of brightness or more within the same field of view as the celestial object to be observed, it is possible to reduce the mirror error and the tracking error to a small value. The optical performance of the optical infrared telescope device can be improved. In addition, the mirror inspection unit 22 and the tracking unit 24
The same applies to the first and second embodiments as well as to accommodate them in one unit, and these devices are rotated about the optical axis 9 as a rotation axis by one rotation driving device 33 and one radial movement device 34. At the same time as moving, it can be moved in a direction perpendicular to the optical axis 9. Therefore, it is possible to easily install the mirror inspection device and the tracking device of the optical device 50 near the focal point where it is difficult to secure a sufficient space.

[0036]

According to the present invention, there is provided an optical apparatus comprising: a mirror inspection unit for detecting distortion of a mirror surface of an optical system based on light from a light source passing through the optical system; and a tracking unit for tracking a light source to be observed. A rotation direction driving device for rotating the mirror inspection unit and the tracking unit around the optical axis of the light to be observed,
A radial driving device for moving the mirror inspection unit and the tracking unit in a direction perpendicular to the optical axis of the light to be observed, and split optical means for distributing the light from the light source via the optical system to the mirror inspection unit and the tracking unit Therefore, even when there is only one bright celestial object in the same field of view as the celestial object to be observed, it is possible to reduce the mirror error and the tracking error, thereby improving the optical performance of the optical infrared telescope device. And the mirror inspection unit and the tracking unit are housed in one unit.
With two radial moving devices, the mirror inspection unit and the tracking unit are rotated about the optical axis 9 as a rotation axis and moved in a direction perpendicular to the optical axis 9 even near the focal point where it is difficult to secure a sufficient space. Can be done.

Further, since the splitting optical means is a wavelength splitting optical element for splitting light according to wavelength, it is possible to easily apply one celestial object to the mirror inspection unit and the tracking unit without attenuating the intensity of incident light. Light can be incident.

Further, since the splitting optical means is a light splitting optical element for splitting light according to the polarization direction, light of one celestial object can be easily incident on the mirror inspection unit and the tracking unit.

Further, the splitting optical means includes a time-division optical path switching optical mechanism for switching an optical path by time-division of light, so that it is inexpensive and can be easily mirrored without attenuating the intensity of incident light. Light of one celestial body can be made incident on the inspection unit and the tracking unit.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing a cross section of a mirror inspection device and a tracking device of an optical device according to a first embodiment of the present invention;

FIG. 2 is a diagram showing a mirror inspection device and a tracking device of the optical device according to the first embodiment of the present invention, together with an optical axis.

FIG. 3 is a diagram schematically showing a cross section of a mirror inspection device and a tracking device of an optical device according to a second embodiment of the present invention;

FIG. 4 is a diagram schematically showing a cross section of a mirror inspection device and a tracking device of an optical device according to a third embodiment of the present invention;

FIG. 5 is a perspective view showing a conventional optical infrared telescope device.

FIG. 6 is a diagram conceptually showing an optical path of a conventional optical infrared telescope device.

FIG. 7 is a diagram schematically showing a cross section of a mirror inspection device and a tracking device of a conventional optical device.

FIG. 8 is a diagram schematically showing a mirror inspection device and a tracking device of a conventional optical device together with an optical axis.

[Explanation of symbols]

9 optical axis, 10 celestial object (observation target), 22 specular inspection unit, 24 tracking unit, 30, 40, 50 optical device, 32
Dichroic mirror (divided optical unit), 33 rotation direction drive unit, 34 radial direction drive unit, 41 polarizing plate (divided optical unit), 51 time division optical path switching optical mechanism (divided optical unit).

Claims (4)

[Claims] A mirror inspection unit that detects distortion of a mirror surface of the optical system based on light of a light source that has passed through the optical system; a tracking unit that tracks a light source to be observed; A rotation direction driving device for rotating the tracking unit around the optical axis of the observation target light as a rotation axis; and moving the mirror inspection unit and the tracking unit in a direction perpendicular to the optical axis of the observation target light. An optical device comprising: a radial driving device for dividing the light from a light source through the optical system to the mirror inspection unit and the tracking unit. 2. The optical device according to claim 1, wherein the division optical unit is a wavelength division optical element that divides light by wavelength. 3. The optical device according to claim 1, wherein the splitting optical unit is a light splitting optical element that splits light according to a polarization direction. 4. The optical device according to claim 1, wherein said splitting optical means includes a time-division optical path switching optical mechanism for switching an optical path by time-division of light.