JP2016102914A - Astronomical object imaging device, astronomical telescope controller, and astronomical telescope control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an astronomical object imaging device which can introduce astronomical objects and improve tracking accuracy.SOLUTION: An astronomical object imaging device has: a telescope lens-barrel 1; a frame 2 supporting the telescope lens-barrel so that it can rotate around two axes, a first axis 3 and a second axis 4; a first motor 32 generating a driving force that rotates the telescope lens-barrel around the first axis; a second motor 42 generating a driving force that rotates the telescope lens-barrel around the second axis; a first driving force transmission mechanism which transmits the driving force generated by the first motor to the first axis; a second driving force transmission mechanism which transmits the driving force generated by the second motor to the second axis; a beam splitter which splits light made incident by an objective lens provided for the telescope lens-barrel into first light and second light different in wavelength; imaging means which exposes the first light for a prescribed time and images it; an image sensor 11 which receives the second light and converts it into astronomical information; and a control part 5 which controls at least either the first motor or the second motor on the basis of the converted astronomical information.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an astronomical telescope control technique and an astronomical imaging technique, and more particularly to a technique for introducing a target celestial body into the field of view of an astronomical telescope and a technique for automatically tracking an astronomical object.

  A cooled CCD is widely used for imaging a celestial body with a telescope. Imaging with a cooled CCD can accumulate light from the target celestial object over a long period of time, so there is an advantage that a bright image can be obtained even with a dark celestial object, but on the other hand, tracking the telescope according to the diurnal motion of the celestial object ( Need to guide). There are generally two types of astronomical telescope mounts for tracking this celestial body: an equatorial mount and a pedestal.

  Here, a conventional equator will be described as an example with reference to FIG. The equatorial mount is a mechanism that rotates the celestial telescope in the celestial direction around the celestial axis 3 (polar axis) installed parallel to the earth's earth axis so that it can be tracked according to the diurnal movement of the target celestial body. And a mechanism for rotating the astronomical telescope in the declination direction about the declination axis 4 perpendicular to the ecliptic axis 3. Specifically, the ecliptic axis 3 and the declination axis 4 are provided with an ecliptic axis encoder 35 and a declination axis encoder 45 for detecting the rotation angle of each axis. Based on the rotation angle detected by the axis encoder 35 and the declination axis encoder 45, the astronomical telescope faces through the pulse generators 34, 44, the motor drivers 33, 43, the motors 32, 42, and the driving force transmission mechanisms 31, 41. Controls the position of the longitude and declination.

  When imaging an celestial object using the equatorial mount, first, the target celestial object is introduced into the field of view of the telescope. In recent years, an automatic introduction function for automatically introducing a target celestial body has been provided in a small telescope mount for amateurs. Here, the automatic introduction function of the target celestial body is a function that obtains and calculates the coordinates of the target celestial object using a microcomputer or the like and automatically points the astronomical telescope in that direction.

  Next, after the target celestial body is introduced into the field of view of the telescope, the direction of the telescope is tracked (guided) according to the diurnal motion of the target celestial body during imaging of the celestial body. As a method of tracking (guide) of this celestial body, there are a method that does not use a guide star or a method that uses a guide star. As the latter, manual guide, automatic tracking, and the like are known.

  In the method that does not use the guide star, after the target celestial body is introduced into the telescope, only the red meridian axis is automatically driven at the time of imaging, but even if the polar axis is aligned fairly accurately, In addition, it is difficult to avoid the phenomenon (tracking error) that the celestial body is shifted in the telescope field of view, and it is unavoidable that the image quality is deteriorated in imaging for a long time.

  On the other hand, among the methods using guide stars, as manual tracking, a bright star near the object to be imaged is used as a guide star. Specifically, a sub-telescope barrel for imaging the guide star is mounted on the equator, and an eyepiece with a crosshair is attached to the sub-telescope barrel so that the guide star does not deviate from the center of the crosshair. The drive adjustment of the red meridian axis and the declination axis is performed manually. With this guide method, it is difficult for the imager to leave the astronomical telescope, and the burden on the imager is great.

  In order to reduce this burden, an automatic tracking system using a sub-telescope barrel is used. That is, as shown in FIG. 6, an auto guide CCD 71 is attached to the sub telescope barrel 7, and a guide star is imaged by the auto guide CCD 71. Based on the information of the guide star imaged by the auto guide CCD 71, the controller 8 passes the red meridian axis 3 through the pulse generators 34, 44, the motor drivers 33, 43, the motors 32, 42, and the driving force transmission mechanisms 31, 41. And the declination axis 4 is automatically adjusted.

  In this method, an automatic guide CCD 71 is installed in the sub-telescope barrel 7 to detect the deviation of the guide star and to control the drive circuit based on the detection signal. Specifically, one or more bright stars in the vicinity of the target celestial body itself or in the vicinity thereof are selected as guide stars, and an image of light incident on the celestial telescope is captured by the auto guide CCD 71. This is based on the idea that if the main telescope barrel 6 is driven so that the guide star is always at a predetermined reference position in the image by the auto guide CCD 71, the tracking error is reduced as a result.

JP-A-8-292376 JP 2000-305024 A

  However, there is a need for an automatic introduction system and an automatic tracking system with higher accuracy. For example, in an automatic tracking system using a sub-telescope so far, a tracking error may occur even if the main telescope can be driven so that the guide star is always at a predetermined reference position within the field of view of the sub-telescope. There was. In addition, it has been considered difficult to provide a scale or the like for indicating the position in the visual field in the main telescope.

  Accordingly, an object of the present invention is to provide an astronomical telescope control device and an astronomical telescope control method capable of improving the accuracy of introduction and tracking of astronomical objects. Other objects of the present invention will become clear from the description of the present specification.

  In order to solve the above-mentioned problems, the invention of claim 1 includes a telescope barrel, a pedestal that supports the telescope barrel so as to be rotatable about two axes of a first axis and a second axis, and about the first axis. Generated by a first motor for generating a driving force for rotating the telescope barrel, a second motor for generating a driving force for rotating the telescope barrel about the second axis, and the first motor. A first driving force transmission mechanism for transmitting a driving force to the first shaft; a second driving force transmission mechanism for transmitting a driving force generated by the second motor to the second shaft; and the telescope barrel. A beam splitter that branches light incident from an objective lens into first light and second light having different wavelengths, an imaging unit that exposes the first light for a predetermined time, and receives the second light. Image center to convert to astronomical information When, the celestial body image pickup apparatus and a control unit for controlling at least one of said first motor and the two motors on the basis of the converted celestial information.

  A second aspect of the present invention is the astronomical imaging device according to the first aspect, wherein the imaging means is a cooled CCD.

  The invention according to claim 3 is the astronomical imaging device according to claim 1 or 2, wherein the first light is transmitted through the beam splitter, and the second light is branched by the beam splitter.

  According to the present invention, the accuracy of introduction and tracking of celestial bodies can be increased.

It is a schematic block diagram of the astronomical imaging device of 1st Embodiment of this invention. It is a block block diagram of the optical system of the astronomical telescope of 1st Embodiment of this invention. 3 is a schematic configuration diagram of a controller 5. FIG. It is an operation | movement flowchart figure of introduction of the astronomical telescope of 1st Embodiment of this invention. It is an operation | movement flowchart figure after the imaging and tracking start of the astronomical telescope of 1st Embodiment of this invention. It is a schematic block diagram of the conventional astronomical imaging device.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. Further, each constituent means described in this embodiment is merely an example, and is not intended to limit the scope of the present invention unless otherwise specified.

[First Embodiment]
FIG. 1 is a schematic configuration diagram of an astronomical telescope according to a first embodiment of the present invention.
Reference numeral 1 denotes a telescope barrel, 11 denotes an auto guide CCD attached to the telescope barrel 1, and 5 denotes a controller.
Ascension axis 3, declination axis 4, drive transmission mechanisms 31, 41, motors 32, 42, motor drivers 33, 43, pulse generators 34, 44, and encoders 35, 45 are the same as in the prior art (see FIG. 6). It is.

  FIG. 2 is a block diagram of the optical system of the telescope barrel 1. Reference numeral 101 denotes an objective lens constituting the objective optical system, 102 denotes a beam splitter, and 103 denotes a cooling CCD. 11 corresponds to the auto guide CCD 11 of FIG.

The objective lens 101 is for the astronomical light to enter the telescope barrel 1 from here.
The beam splitter 102 is a beam splitter that branches light incident from the objective lens 101 into light having different wavelengths. For example, it is assumed that visible light is transmitted and infrared light is branched. However, the wavelength region of the transmitted light may be an infrared region, an ultraviolet region, an X-ray region, or a combination thereof in addition to the visible region, and the wavelength region of the branched light may be transmitted light. In addition to the infrared region, the visible region, the ultraviolet region, the X-ray region, or a combination thereof may be used as long as they are different from the wavelength region.

  The cooling CCD 103 is an image obtained by exposing the light of the celestial body for a predetermined time. In addition to the cooling CCD 103, a digital camera or the like that exposes astronomical light for a predetermined time may be used. Thereby, even if the light quantity of a target celestial body is small, it can image. In this case, for example, it is generally used for visible light imaging. As shown in FIG. 2, the visible light transmitted through the beam splitter 102 is received by the cooling CCD 103. As described above, for example, if the beam splitter 102 transmits visible light, a decrease in the amount of visible light in the beam splitter 102 can be suppressed. Therefore, a decrease in the amount of visible light received by the cooling CCD 103 can be suppressed. Note that depending on the type of wavelength of light transmitted through the beam splitter 102, as a cooling CCD, in addition to visible light imaging, infrared imaging, ultraviolet imaging, X-ray imaging, or a combination thereof may be used. it can.

  The auto guide CCD 11 includes an infrared CCD image sensor that receives infrared rays branched by the beam splitter 102. As described above, for example, if the beam splitter 102 branches the infrared rays, the amount of light received by the auto guide CCD 11 can be reduced. When the wavelength region of the light branched by the beam splitter 102 is not the infrared region but the visible region, the ultraviolet region, the X region, or a combination thereof, as a CCD image sensor provided in the auto guide CCD 11, For visible light, for ultraviolet light, for X-rays, or a combination thereof can be used.

FIG. 3 is a schematic configuration diagram of the controller 5.
The controller 5 is connected to the ecliptic axis information input means 501, the declination axis information input means 502, and the pulse generators 34 and 44 to which the information of the respective rotation angles detected by the ecliptic axis encoder 35 and the declination axis encoder 45 is input. Instruction information output means 503 for outputting instruction information, imaging celestial information input means 504 to which celestial information imaged by the auto guide CCD 11 is inputted, and a star holding information relating to a star catalog (a star catalog) near the target celestial body Table information holding means 505, guide star selection holding means 506 for selecting a guide star from the captured celestial information, and guide star centroid calculating means 507 for calculating the centroid of the pixel on the auto guide CCD 11 for the selected guide star. , Correction instruction information calculation means 508 for calculating the correction value of the instruction information, information on the target celestial body (position information and celestial body Referred etc.) or other information outside of the operation unit (Fig includes an external communication unit 509 for inputting and outputting the drawing), the other CPU or the like (figure is omitted).

  Note that the star catalog information holding unit 505 temporarily holds the star catalog information in the vicinity of the target celestial body input via the external communication unit 509. However, the star list information holding unit 505 may be configured to store the existing star list library in a nonvolatile manner so that the controller 5 can calculate the star list information around the target celestial body. Further, instead of using this star catalog information holding means 505, not only the star catalog information in the vicinity of the target celestial body is calculated by an external operation unit or the like, but also the star catalog information is stored, via the external communication means 509. The stored astronomical information may be input to the controller 5.

Next, the operation of the astronomical telescope of this embodiment will be described.
FIG. 4 is an operation flowchart for introducing the astronomical telescope. When the introduction is started, the longitude and declination information (target coordinates) of the target celestial body is input from the external communication unit 509 to the controller 5 via the external communication unit 509 (step S41). Further, star list information around the target celestial body is input to the external communication means 509 from an external operation unit (not shown), and the star list information is held in the star list information holding means 505 (step S42).

  Next, the controller 5 outputs introduction instruction information from the instruction information output means 503 to the pulse generators 34 and 44 so that the telescope barrel 1 is directed in the direction of the input target coordinates. Thereby, the motor drivers 33 and 43 drive the motors 32 and 42, and the driving force is transmitted to the ecliptic axis 3 and the declination axis 4 via the driving force transmission mechanisms 31 and 41 (step S43). At this time, the controller 5 may be configured such that the correction instruction information calculation means 508 corrects the target coordinates based on correction data resulting from a right angle error or an installation error of the equator.

  Subsequently, the information of the celestial body imaged by the auto guide CCD 11 is input from the imaging information input means 504 to the controller 5 (step S44). As shown in FIG. 2, the imaged information of the celestial body is obtained by digitizing the infrared light incident from the objective lens 101 and branched by the beam splitter 102 by the auto guide CCD 11.

Subsequently, the correction instruction information calculation unit 508 compares the astronomical information imaged by the auto guide CCD 11 with the star information in the vicinity of the target celestial body held in the star table information holding unit 505 to determine whether or not there is a deviation. (Step S45). As a method of comparing the two, for example, the star array when the target celestial object comes to the center in the field of view of the astronomical telescope is virtually identified from the star catalog information, and the identified virtual star array and imaging are performed. And a method of comparing the star information of the astronomical information.
When it is determined that there is a difference between the two, the correction instruction information calculation unit 508 calculates a correction value of the instruction information so that the direction of the astronomical telescope is directed toward the target celestial body by the amount of the difference (error). (Step S46). Then, the controller 5 outputs the corrected instruction information to the pulse generators 34 and 44 from the instruction information output means (step S47). Thereby, the ecliptic axis 3 and the declination axis 4 are automatically adjusted via the motor drivers 33 and 43, the motors 32 and 42, and the driving force transmission mechanisms 31 and 41.

The controller 5 repeats the above-described operation until it is determined that there is no difference between the imaging celestial body information and the star catalog information (step S44 to step S47). Then, when it is determined that there is no difference between the imaged celestial body information and the star catalog information, the introduction of the target celestial body ends.
This completes the automatic introduction of celestial bodies.

  Subsequently, imaging / tracking of the target celestial body is started. That is, visible light incident from the objective lens 101 passes through the beam splitter 102 and is exposed for a predetermined time by the cooling CCD 103 to be imaged. On the other hand, automatic tracking of celestial bodies is performed during this time. Specifically, the instruction information output means 503 of the controller 5 outputs tracking instruction information to the pulse generator 34 so that the rotational speed of the ecliptic axis 3 is the same as the diurnal speed of the celestial body. Accordingly, the red meridian axis is driven via the motor driver 33, the red meridian motor 32, and the driving force transmission mechanism 31, and automatic tracking is started.

  FIG. 5 is an operation flowchart after the start of imaging and tracking of the astronomical telescope according to the first embodiment of the present invention. When imaging / tracking is started, information on the celestial body imaged by the auto guide CCD 11 is input to the controller 5 from the imaging celestial body information input means. This imaging celestial body information is obtained by the infrared rays incident from the objective lens 101 being branched by the beam splitter 102 and picked up by the auto guide CCD 11.

  The guide star selection / holding means 506 selects a guide star from the imaged astronomical information. Further, the guide star center of gravity calculating means 507 calculates the position of the center of gravity of the selected guide star, and the guide star specifying and holding means 506 holds the position of the center of gravity (step S51). The center of gravity of the guide star is described here as being specified by the position (Xc, Yc) of the pixel (pixel) on the auto guide CCD 11, but is not necessarily limited thereto. The selection of the guide star and the calculation / maintenance of the position of the center of gravity may be performed before the automatic tracking is started.

  During imaging of the target celestial body, imaging celestial body information is input from the imaging celestial body information input means 504 to the controller 5. The guide star centroid calculating means 507 calculates the position of the centroid of the guide star in the imaged astronomical information (step S52).

  The correction instruction information calculation means 508 shifts to the center of gravity position (Xc, Yc) of the guide star information held in the guide star selection holding means 507 and the center of gravity position (Xc ′, Yc ′) of the imaged celestial guide star. It is determined whether or not there is (step S53).

  If it is determined that there is a deviation in the center of gravity position of the guide star, the correction instruction information calculation unit 508 calculates an error amount of the center of gravity position of the guide star and corrects the rotational speed of the red meridian axis by the error amount. The tracking instruction information is corrected (step S54). The controller 5 outputs the corrected tracking instruction information to the pulse generator 34 from the instruction information output unit 503 (step S55). Based on this tracking instruction information, the pulse generator 34 transmits the corrected transmission pulse to the motor driver 33, and the motor driver 33 drives the red motor 32 in accordance with the corrected transmission pulse, thereby driving force. The red meridian axis 3 is driven via the transmission mechanism 31.

On the other hand, when it is determined that no deviation has occurred (step S53), the tracking instruction information is not corrected.
The controller 5 determines whether or not to complete the imaging / tracking, and repeats the above-described operation until the imaging / tracking is completed (from step S52 to step S56).

[Modification]
In the above-described automatic tracking, an example in which only the red meridian axis is driven has been described. As described above, in automatic tracking using a normal equatorial mount, one that drives only the ecliptic axis and does not drive the declination axis is generally used. This means that if the red meridian axis 3 (polar axis) is installed in parallel with the earth's earth axis, it is accurate if only the red meridian axis 3 (polar axis) is driven according to the diurnal motion of the celestial body. This is based on the idea that tracking is possible.

  However, in actual imaging, a shift may occur in the declination direction. Therefore, the astronomical telescope of the present invention may be configured to drive not only the ecliptic axis but also the declination axis during automatic tracking.

  Referring to FIG. 5 as an example, during imaging of the target celestial object, the guide star centroid calculating means 507 calculates the centroid position (Xc ′, Yc ′) of the guide star from the imaging celestial information (step S52), and the correction instruction information calculating means. 508 indicates whether or not there is a difference between the gravity center position (Xc, Yc) of the guide star information held in the guide star selection holding means 507 and the gravity center position (Xc ′, Yc ′) of the imaged celestial guide star. Judgment is made (step S53).

  When it is determined that there is a deviation in the center of gravity position of the guide star, the correction instruction information calculation unit 508 calculates an error in the center of gravity position of the guide star and corrects the rotation speed of the red meridian axis by the error. In addition, the tracking instruction information is corrected so as to rotate the declination axis (step S54). The controller 5 outputs the corrected tracking instruction information from the instruction information output means 503 to the pulse generator 44 in addition to the pulse generator 34 (step S55). Based on the tracking instruction information, the pulse generators 34 and 44 transmit transmission pulses to the motor drivers 33 and 43, so that the motor drivers 33 and 43 drive the red longitude motor 32 and the declination motor 42 according to the transmission pulses. The driving force is transmitted to the red meridian axis 3 and the weft axis 4 via the driving force transmission mechanisms 31 and 42.

  Such automatic tracking is repeated until imaging / tracking is completed (from step S52 to step S56).

  Although the present invention is configured as described above, various modifications can be made without departing from the scope of the present invention. For example, the order of the steps described above can be changed as appropriate. In addition, the present invention can be applied to a course table. In this case, since the east, west, north, and south of the image obtained according to the direction in which the astronomical telescope is directed changes, it is necessary to perform calculation in consideration of rotation.

DESCRIPTION OF SYMBOLS 1 ... Telescope barrel, 2 ... Equatorial, 3 ... Red meridian axis, 4 ... Declination axis, 5 ... Controller, 6 ... Main telescope barrel, 7 ... Sub telescope barrel, 8 ... Controller, 11 ... Auto guide CCD, 31/41 ... Driving force transmission mechanism, 32 ... Inclination motor, 42 ... Declination motor, 33/43 ... ..Motor driver, 34.44 ... pulse generator, 101 ... objective lens, 102 ... beam splitter, 103 ... cooling CCD, 501 ... red meridian axis information input means, 502 ... Declination axis information input means, 503 ... Instruction information output means, 504 ... Imaging celestial body information input means, 505 ... Star catalog information holding means, 506 ... Guide star selection holding means, 507 ... Guide star center of gravity calculation means, 508... Correction instruction information Calculating means, 509 ... external communication means

Claims (3)

A telescope tube,
A gantry that supports the telescope barrel so as to be rotatable about two axes of a first axis and a second axis;
A first motor for generating a driving force for rotating the telescope barrel about the first axis;
A second motor for generating a driving force for rotating the telescope barrel about the second axis;
A first driving force transmission mechanism for transmitting the driving force generated by the first motor to the first shaft;
A second driving force transmission mechanism for transmitting the driving force generated by the second motor to the second shaft;
A beam splitter that branches light incident from an objective lens included in the telescope barrel into first light and second light having different wavelengths;
Imaging means for exposing and imaging the first light for a predetermined time;
An image sensor that receives the second light and converts it into astronomical information;
A control unit for controlling at least one of the first motor and the two motors based on the converted astronomical information;
An astronomical imaging device having: The astronomical imaging device according to claim 1,
An astronomical imaging device, wherein the imaging means is a cooled CCD. The astronomical imaging device according to claim 1 or 2, wherein
The astronomical imaging device, wherein the first light is transmitted through the beam splitter and the second light is branched by the beam splitter.

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