JPH05249355A - Filter attaching/detaching device - Google Patents

Abstract

PURPOSE:To provide a filter attaching/detaching device in which plural filters can be simultaneously attached/detached on the optical axis of an optical system by simple operation, working effectiveness is improved, and also whose miniaturization can be realized. CONSTITUTION:This device is provided with a filter holding means, and a rotary shaft 3 which is different from the optical axis and in parallel with the optical axis, and the filter holding means is linked with the periphery of the rotary shaft 3 in a state where it can rotate and move in a shaft direction, the filter is attached/detached on the optical axis by the rotation of the filter holding means on the periphery of the rotary shaft, and the attaching position of the filter on the optical axis is decided by the moving of the filter holding means in the shaft direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for inserting and removing an optical filter used in the fields of optics and electromagnetism on and from the optical axis, and in particular, a filter suitable for improving operability and downsizing the device. Insertion / detachment device.

[0002]

2. Description of the Related Art Conventionally, since an optical filter can easily realize adjustment of light intensity, selection of a specific wavelength, branching of an optical path, etc.,
Widely used in the fields of optics and electromagnetics. In most cases, these are used by simply fixing them using a commercially available filter holder, except for a special case where they are directly incorporated in an experimental apparatus or fixed at a specific place. The shape, size, material, etc. of the filter differ depending on the intended use.
In accordance with these, various holders are commercially available, and recently, it has become possible to select the holder quite freely according to the purpose of use. FIG. 2 shows an example of a typical holder. Figure 2
In (a) shown in Fig. 4, a bottom surface of the recess of the holder is a flat surface with a narrow width, and a filter having a narrow flat surface on one side is inserted, and the filter is sandwiched and fixed in the recess. It is a holder for fixing a single sheet. Further, (b) is a holder for supporting a filter at three points, and is a holder for fixing a plurality of filters each having a quadrangular shape or a substantially circular outer shape. On the other hand, the present applicants have evaluated various characteristics centering on the image quality of high-definition TV cameras for image capturing. In these evaluation experiments, an optical filter (ND filter made of glass) is used for adjusting the incident light intensity of the optical image. Incident light control for a TV camera is generally performed by an optical diaphragm provided between the image pickup surface and the imaging lens. However, when evaluating image resolution when light of various intensities is incident, Since the resolution of the optical lens system changes with the change of the diaphragm, it is necessary to perform the experiment by keeping the diaphragm constant and adjusting the incident light intensity by the optical filter arranged in front of the imaging lens. To fix the filter at this time, a plurality of commercially available one-piece filter holders are used. In order to realize the characteristic evaluation of the images taken by the TV camera under various incident light intensity conditions, the optical filters are changed one after another or several filters are used in a stacked manner.

[0003]

In the above-mentioned prior art, in the optical system, when the optical filters are changed one after another or several filters are piled up to achieve various incident light intensity conditions, As shown in FIG. 2, currently used filter holders are of the type (a) for fixing one filter or the type (b) for fixing a plurality of filters to a rigid. Therefore, the following problems occur. That is, in the case of a holder that holds one filter, the work of attaching and detaching the filter to achieve various incident conditions becomes complicated, so the experimental efficiency is poor, and in the holder that holds a plurality of filters, a large space ( Long dimension) is required. In a high-definition TV camera for image shooting, an experimental system that evaluates various characteristics centering on image quality requires a filter to be placed in front of an imaging lens that forms an optical image on the imaging surface. When the dimension in the direction becomes longer, the angle of view becomes smaller and the field of view is limited, so
When arranging the holders that hold a plurality of filters, it is preferable that the space (length) required for this arrangement be as short as possible. Further, as shown in FIG. 3A, a rotary filter holder in which a plurality of holders 10a, 10b ... Of the type shown in FIG. 2A are fixed to a rotating body, or a filter 10a as shown in FIG. A method of producing a plate-shaped rotary filter holding plate 30 provided with a plurality of holes for holding 10b ... Is conceivable, but the holder body becomes large and is not suitable for desk experiments and the like. In view of the above, an object of the present invention is to improve such problems and to be able to hold various types of filters having different shapes and sizes, and to easily perform a filter changing operation on the optical axis. A filter insertion / removal device capable of inserting the above filters into the optical axis at the same time, having a short dimension in the optical axis direction when inserting the filters into the optical axis, and being compact, and capable of inserting and removing the filters from different directions. To provide.

[0004]

To achieve the above object, a filter insertion / removal device according to the present invention comprises one or a plurality of holders for fixing a filter and an arm for supporting the holder. A filter holding means and one or a plurality of rotating shafts parallel to the optical axis, and the rotating shaft so that the filter holding means is rotatable around the rotating shaft and movable in a direction parallel to the optical axis. The filter holding means is rotated around the rotation axis to insert or remove the filter on the optical axis, and the movement of the filter holding means in the rotation axis direction determines the insertion position on the optical axis of the filter. It is characterized in that it is configured to do. Further, the filter insertion / removal device of the present invention has one or a plurality of filter holding means and one or a plurality of columnar members movable in a direction parallel to the optical axis. The filter is coupled to the columnar member so as to be rotatable around the axis of the columnar member, and the filter holding means is rotated around the axis of the columnar member to insert or remove the filter onto the optical axis. The filter is characterized in that the insertion position on the optical axis of the filter is determined by the movement in the direction parallel to the axis.

[0005]

In the present invention, it is possible to connect a plurality of filter holding means on the same rotary shaft or columnar member, so that filters having different transmittances can be inserted on the same optical axis or from the optical axis. Can be desorbed. Further, by connecting the individual filter holding means so as to be rotatable around the rotation shaft or the shaft of the columnar member, it becomes possible to insert and remove the filters separately and independently. Furthermore, by making the filter holding means or the columnar member movable in the direction parallel to the optical axis, it becomes possible to arbitrarily determine the insertion position of the filter on the optical axis. Also, by providing a plurality of rotary shafts or columnar shafts or a plurality of combinations thereof, it becomes possible to insert a plurality of filters from different directions in combination. As a result, the operability of the filter insertion / removal device can be improved and the device can be downsized.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a view showing a part of a filter insertion / removal device according to the first embodiment of the present invention, and FIG. 4 is a view showing a holder portion according to the first embodiment of the present invention. FIG. 5 is a diagram showing a method of connecting the arm portion and the rotary shaft in the first embodiment of the present invention. In the present embodiment, as shown in FIG. 1, holder portions 1a to 1e for directly fixing the filter, arm portions 2a to 2e for rotatably and movably coupling the holder portion to the rotary shaft 3, and parallel to the optical axis. Rotating shaft 3, stoppers 41 and 42 for deciding the position of the filter holding means at the time of inserting / removing the filter to / from the optical axis, and the rotating shaft 3, stoppers 41 and 42
Is composed of a pair of plates 5 (one of which is not shown) for spatially fixing the. The rotating shaft 3 is fixed to the plate so that the rotating shaft 3 does not rotate and does not move in the rotating shaft direction. The filter to be used is 5
Various sizes such as 0 mm □ and 50 mmφ are possible, but in the present embodiment, the case of using a 50 mm □ ND filter made of glass will be described as an example. As shown in FIG. 4, the holder portion 1 has a structure in which the filter 10 can be fitted from the side surface and easily fixed by the screw 6. In addition, in this embodiment, the screw 6 is fixed at one point for simplification of description. However, in order to prevent the filter 10 from being damaged or scratched, not only the screw 6 is fixed at one point but a felt. It is desirable to use such as a cushioning material so that pressure is evenly applied to the entire side surface of the filter 10. The holder portion 1 is connected to the rotary shaft 3 by the arm portion 2. Since the arm portion 2 is mounted rotatably and movably around the rotary shaft 3, the size of the connecting portion of the arm portion 2 is slightly larger than the size of the rotary shaft 3. In order to further improve the precision, as shown in FIG. 5, a coupling method using a ball bearing at the coupling portion with the rotary shaft 3 is adopted. In FIG. 5, a radial direction ball bearing 21 for enabling rotation about a rotation axis, and
A thrust direction ball bearing 22 is used to enable movement in the rotation axis direction. The holder portions 1a to 1e in this embodiment are configured to be supported and coupled by the arm portions 2a to 2 using two screws. Therefore, by preparing several kinds of holder parts according to the size and shape of the filter to be used, it is possible to deal with different filters only by changing the holder part. Further, the holder portion may be processed and manufactured integrally with the arm portion.
Further, the insertion of the filter 10 on the optical axis and the removal of the filter 10 from the optical axis are performed by manually rotating the filter holding means including the holder part and the arm part to which the filter 10 is attached around the rotary shaft 3. By.

Next, the position of the filter when it is inserted into the optical axis and when it is detached from the optical axis will be described. FIG. 6 is a diagram showing the spatial arrangement of each component in the first embodiment of the present invention.
In this embodiment, each component of the filter insertion / removal device having the two rotation shafts 3 and 3'is arranged as shown in FIG. 6 when viewed from a plane perpendicular to the optical axis. The position of the filter holding means when the filter is inserted is determined by the stoppers 41 and 41 ',
The positions of the filter holding means at the time of detachment are the stoppers 42, 42 '.
The filter holding means rotates about the rotation axis 3 by a constant angle as determined by In this embodiment, these two sets of stoppers 41, 42 and 41 ', 42' are parallel to the rotary shafts 3, 3 ', and the rotary shafts 3, 3'are sandwiched on a plane perpendicular to the direction of gravity. They are evenly spaced. Also,
With the filter 10 fixed to the holder portions 1a, 1b, 1a ', 1b', the center of gravity of the filter holding means is moved from the rotation shafts 3, 3'to the center of the filter when the filter holding means is inserted or removed. Since it is configured so that it can be secured, a stable position of the filter 10 using gravity can be secured without separately providing a dedicated means for fixing, and the filter 10 can be inserted into and removed from the optical axis. It can be done easily. Further, the insertion position of the filter on the optical axis can be adjusted by moving the filter holding means in a direction parallel to the optical axis. That is, the filter 10 can be inserted and removed at an arbitrary position within the range of the length of the rotating shaft 3. Further, if a plurality of rotary shafts 3 and stoppers 41 and 42 are provided and a plurality of filter holding means are connected to the respective rotary shafts, as shown in FIGS. Multiple filters can be inserted at the same time or in combination.

Here, the configuration when the filter insertion / removal device of this embodiment is used in an evaluation experiment of a TV camera will be shown.
FIG. 7 is a diagram showing an application example of the filter insertion / removal device according to the first embodiment of the present invention. The TV camera evaluation system of the present embodiment has an optical shutter 3 fixed vertically to a base plate.
8, holder parts 1a to 1f, 1a ', arm part 2a
~ 2f, 2a ', rotating shafts 3, 3', plates 5, 5 ',
The filter insertion / detachment device including the stoppers 41, 41 ′, 42, 42 ′ is configured such that the light passing through the filter inserted in the optical axis is imaged on the TV camera 31 by the optical lens 32. .. In this case, upright plate 4
0, the plates 5 and 5'are vertically connected to the base plate 39, and the TV camera 31 and the optical lens 32 are fixed to the upright plate 40 so that their centers coincide with the optical axis. The filter insertion position in this embodiment is between the optical lens 32 and the optical shutter 38 (in this embodiment, 1
Besides 0 mm to 20 mm), it can be provided in front of the optical shutter 38 (on the side facing the optical lens 32 across the optical shutter 38).

(Second Embodiment) FIG. 8 is a view showing a method of connecting an arm portion and a columnar member in a second embodiment of the present invention. In the present embodiment, unlike the first embodiment (method in which the filter holding means can be moved in parallel with the optical axis on the rotation axis), the method in which the columnar member itself coupled to the arm portion is moved in parallel with the optical axis. To adopt. Note that in this embodiment as well, 50
An example will be described in which a ND filter made of mm square glass is used. The appearance of this embodiment is almost the same as that of the first embodiment, and the holder portion has the same structure. This holder part is supported by the arm part 2 to form a filter holding means, and the filter holding means is rotatable about the axis of the columnar member 33 and is radial so as not to move in the axial direction of the columnar member 33. A directional ball bearing 21 'is used to rigidly secure and join the columnar member 33. In this case, insertion and removal of the filter on the optical axis are performed by manually rotating the filter around the axis of the columnar member 33 as in the first embodiment, and the filter insertion position on the optical axis is also set. Unlike the first embodiment, the adjustment is performed by moving the columnar member 33 to which the filter holding means is coupled in the direction parallel to the optical axis. Specifically, the columnar member 33 is slid to a desired insertion position of the filter, and the filter holding means is manually rotated around the axis of the columnar member 33 to be inserted. Also,
Similar to the first embodiment, the filter holding means rotates around the axis of the columnar member 33 by a constant angle. Further, in this embodiment as well, a plurality of columnar members 33 and the stoppers 41 and 42 shown in FIGS. 6 and 7 are provided, and a plurality of filter holding means are coupled to the respective columnar members, so that the optical axis is moved to the optical axis. It is possible to insert a plurality of filters simultaneously or in combination from different columnar members located at different positions. In order to smooth the movement of the columnar member 33 in the direction parallel to the optical axis, it is effective to use a ball bearing or the like for the supporting portion (the plates 5 and 5 ′ in FIG. 7) of the columnar member 33. Here, if the number of filter holding means coupled to the columnar member is N and the thickness of the filter holding means is t (mm), the movable range (stroke) D (mm) of the columnar member.
May satisfy D ≧ N (t−1).

In the above embodiments, the material of the rotary shaft and the columnar member is made of stainless steel in consideration of the wear when the filter holding means is rotated or slid, and the other components are made of aluminum which can reduce the weight. To do. In addition, in order to suppress stray light due to light reflection etc. as much as possible when used in an optical experiment, all except the filter are subjected to black alumite treatment or black paint coating treatment. In addition, the cross-sectional shape of the columnar member in the axial direction is such that the columnar member is movable in the axial direction,
It suffices if they are the same in the axial direction, and the cross-sectional shape of the rotating shaft is such that the filter holding means can move in the direction parallel to the optical axis.
It may be the same in the axial direction. In addition to this, it goes without saying that a filter insertion / removal device having the same performance as the first and second embodiments can be constructed by using a plurality of rotary shafts and a plurality of columnar members at the same time. Furthermore, as an embodiment of the present invention, for example, by modifying the holder part of the filter into a holder for the analysis sample, it can be applied as a sample holder for various analyzers, and the holder part can have a mesh of various roughnesses. It is conceivable that the powder samples are provided and arranged vertically (in the direction of gravity) to screen the powder sample. Furthermore, it is easy to construct a slide projector using the present invention.

[0011]

According to the present invention, it is easy to insert and remove filters for changing a plurality of filters, work efficiency is improved, and two or more filters can be combined and inserted at the same time. The size of the filter holding means in the optical axis direction can be shortened, and at the same time, the size of the device can be reduced.

[0012]

[Brief description of drawings]

FIG. 1 is a diagram showing a part of a filter insertion / removal device according to a first embodiment of the present invention.

FIG. 2 is a view showing a conventional filter holder.

FIG. 3 is a view showing a conventional filter holder.

FIG. 4 is a diagram showing a holder portion according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a method of connecting the arm portion and the rotating shaft in the first embodiment of the present invention.

FIG. 6 is a diagram showing a spatial arrangement of each component in the first embodiment of the present invention.

FIG. 7 is a diagram showing an application example of the filter insertion / removal device according to the first embodiment of the present invention.

FIG. 8 is a diagram showing a method of connecting the arm portion and the columnar member in the second embodiment of the present invention.

[Explanation of symbols]

 1 Holder Part 1a Holder Part 1b Holder Part 1c Holder Part 1d Holder Part 1e Holder Part 1f Holder Part 2 Arm Part 2a Arm Part 2b Arm Part 2c Arm Part 2d Arm Part 2e Arm Part 2f Arm Part 3 Rotating Shaft 5 ' Plate 5'Plate 6 Screw 10 Filter 21 Ball bearing 21 'Ball bearing 22 Ball bearing 30 Filter holding plate 31 TV camera 32 Optical lens 33 Columnar member 38 Optical shutter 39 Base plate 40 Upright plate 41 Stopper 41' Stopper 42 Stopper 42 'Stopper

Claims (21)

[Claims] 1. A device for inserting and removing a filter for controlling the intensity of light on the optical axis of an optical system, wherein the filter holding means and the filter holding means are parallel to the optical axis. One or a plurality of rotary shafts that are movable in various directions and that are rotatably held about the axis, and the filter holding means is rotated around the axis of the rotary shaft to insert and remove the filter onto the optical axis. A filter insertion / detachment device, characterized in that the filter holding means is moved in the axial direction of the rotating shaft to determine the insertion position of the filter. 2. A first positioning means for determining the position of the filter holding means when inserting the filter on the optical axis, and a position of the filter holding means for detaching the filter from the optical axis. The filter insertion / removal device according to claim 1, further comprising: 3. The filter holding means comprises a holder part for fixing the filter, and an arm part for supporting the holder part and rotatably coupled to the rotary shaft. 2. The filter insertion / removal device described in 2. 4. The angle formed between the rotation surface and the rotation axis, which is created when the filter holding means rotates around the rotation axis, is 0.
4. The filter insertion / removal device according to claim 1, wherein the filter insertion / removal device is in the range of 180 ° to 180 °. 5. The filter insertion / removal device according to claim 1, wherein the rotary shaft is a cylindrical member. 6. The second positioning means and the first positioning means are arranged so that the filter holding means rotates about the rotation axis by a constant angle. Filter insertion and removal device. 7. A plurality of rotating shafts to which the one or a plurality of filter holding means are connected are provided, and a filter is inserted into and removed from the optical axis from different rotating shafts. The described filter insertion / removal device. 8. When the filter is inserted into or removed from the optical axis, the position of the center of gravity of the filter holding means in the state of holding the filter is the direction of gravity acting through the center of the rotating shaft. 8. The filter insertion / removal device according to claim 2, wherein the first positioning means and the second positioning means are arranged so as to come to a sandwiching position. 9. The filter insertion / removal device according to claim 1, wherein the distance between the center of the rotation axis and the center of the optical axis is set so that the center of the filter and the center of the optical axis coincide with each other. .. 10. When inserting the filter onto the optical axis,
The first positioning means is arranged so that the center of the filter coincides with the center of the optical axis.
9. The filter insertion / removal device according to item 9. 11. A device for inserting and removing a filter for controlling the intensity of light on the optical axis of an optical system,
One or a plurality of columnar members movable in the optical axis direction and parallel to the optical axis, and means for holding the filter, which are coupled to the columnar members so as to be rotatable around the axis of the columnar members. The filter holding means is rotated around the axis of the columnar member to insert and remove the filter on the optical axis, and the columnar member is moved in a direction parallel to the optical axis to insert the filter on the optical axis. A filter insertion / removal device characterized by determining a position. 12. A first positioning means for determining the position of the filter holding means when the filter is inserted on the optical axis, and a first positioning means for determining the position of the filter holding means when the filter is detached from the optical axis. The filter insertion / removal device according to claim 11, further comprising two positioning means. 13. The filter holding means comprises a holder portion for fixing the filter, and an arm portion for supporting the holder portion and rotatably coupled to the shaft of the columnar member. The filter insertion / removal device according to claim 11. 14. The angle between the rotation surface created when the filter holding means is rotated about the axis of the columnar member and the columnar member is 0 ° to 180 °.
13. The filter insertion / removal device according to item 13. 15. The filter insertion / removal device according to claim 11, wherein the columnar member is a columnar member. 16. The first positioning means and the second positioning means are arranged such that the filter holding means is rotated around the columnar member by a predetermined angle. Filter insertion and removal device. 17. A plurality of columnar members having one or a plurality of filter holding means coupled thereto are provided, and the filters are inserted into and removed from the different columnar members on the optical axis. The described filter insertion / removal device. 18. When the filter is inserted into or removed from the optical axis, the position of the center of gravity of the filter holding means in a state of holding the filter acts by gravity passing through the center of the axis of the columnar member. 18. The filter insertion / removal device according to claim 12, wherein the first positioning means and the second positioning means are arranged so as to be positioned so as to sandwich the direction. 19. The filter insertion / removal according to claim 11, wherein the distance between the columnar member and the center of the optical axis is set so that the center of the filter coincides with the center of the optical axis. apparatus. 20. The position of the first positioning means is set such that the center of the filter coincides with the center of the optical axis when the filter is inserted on the optical axis.
The filter insertion / removal device according to 2-19. 21. When the thickness of the filter holding means is t mm and the number of the filter holding means coupled to the columnar member is N, the movable range Dmm of the columnar member is D ≧ t.
The filter insertion / removal device according to claim 11, wherein the filter insertion / removal device is (N-1).