JP2682758B2 - Pan-tilt mechanism for TV door phone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pan / tilt mechanism for a TV door phone, and more particularly to a pan / tilt mechanism for a TV door phone equipped with a pan / tilt mechanism using a prism.

[0002]

2. Description of the Related Art When a call button of a camera-equipped entrance device is pressed by a visitor, the occupant checks the image of the visitor on the television monitor screen of the main unit of the TV intercom, and visits the entrance device. In recent years, the introduction of a camera having a pan-tilt mechanism, which has a wide imaging range and is capable of imaging a relatively wide range of objects by a camera unit, as an entrance unit of a TV door phone for talking with a person has increased.

[0003] The present applicant has also proposed an improvement of a camera-equipped front door unit provided with such a pan / tilt mechanism (Jpn.
No. -121651, Japanese Utility Model Application No. 2-127778, Japanese Utility Model Application No. 3-9818, Japanese Utility Model Application No. 3-9826, Japanese Utility Model Application No. 3-1
No. 3982). Generally, in the case of a manual type, as shown in FIGS. 7A and 7B, the CCD device J with a lens barrel is fixed to a movable table K, and the movable table K is provided with a case L having a concave concave surface. It is fixed by screws Q to a plate P that fixes the entire camera. The case L is provided with a hole R. To pan and tilt the camera, the screw Q is loosened and the movable table K is tilted with respect to the case L. Using the hole R provided in the case L, the camera is moved to an arbitrary angle, and the moving base K on which the camera is fixed is fixed again with a screw.

In the case of the electric type, as shown in FIGS. 6 (a) and 6 (b), the CCD device A with a lens barrel is fixed to a movable table B, and the movable table B has an arm for inclining the movable table B. C is 2
The book is installed. The head G of the arm C is gripped by the surrounding portion F projecting from the lower surface of the moving table B, and the lower portion H of the arm C is screwed and screwed into the collar portion I of the corresponding screw structure. The brim portion I of each of the two arms C is 2 in the drive portion E.
Are connected to respective motors (not shown). In addition, the drive unit E is provided with a boss D that serves as a fulcrum when the movable table B is tilted.

To pan and tilt the camera, a drive signal is externally sent to the motor of the drive unit E, and the rotation of the motor is transmitted to the gear to rotate the collar unit I. The rotation of the collar portion I relatively rotates the arm C and causes the extension and contraction of the arm C,
The movable table B is tilted with the boss D as a fulcrum, and the camera can be pan-tilted in any direction.

[0006]

In the conventional pan / tilt mechanism described above, when the manual type is used, the pan / tilt mechanism is relatively small, but the accuracy is not high, and when it is electrically operated, the mechanism is complicated. Therefore, the number of parts is large, it is difficult to manufacture high-precision parts, high assembly precision is required, and part management is complicated. In addition, there are many sliding parts between each part, there is also inconvenience due to wear of each part, and further, although the accuracy is high, the overall shape of the pan-tilt mechanism becomes large due to the inclination based on the extension and contraction of the arm, and by extension, the entrance subunit itself. Hindered the miniaturization of.

[0007]

An object of the present invention is to solve the above-mentioned conventional problems, and it is possible to expand the image pickup range of the camera vertically and horizontally with high accuracy, simple mechanical structure, downsizing of the pan-tilt mechanism. It is an object of the present invention to provide a pan / tilt mechanism for a TV door phone.

[0008]

In order to achieve this object, a pan / tilt mechanism for a TV door phone according to the present invention is a lens of a camera used in a child device of a TV door phone that images a visitor and displays an image on a TV screen. In front of the, two cylindrical prisms having a light entrance / exit surface in the direction of the axis of the substantially cylindrical column that deflects the light that images the visitor to enter the lens of the camera are formed in the direction of the axis of the column. The two prismatic prisms are arranged relative to each other by arranging prism faces that are orthogonal to each other in sliding contact with each other, and providing a prism rotation drive mechanism for rotating each prismatic prism on each cylindrical side face of each prismatic prism. The image pickup range of the camera is expanded vertically and horizontally by rotating the camera.

[0009]

In this pan / tilt mechanism for a TV intercom, the pan / tilt mechanism is used to rotate the cylindrical prism by driving the prism rotation drive mechanism and deflect the light for picking up the image of the visitor at an arbitrary angle to enter the lens of the camera. The size of the camera can be reduced, the mechanism is simple, the precision of the mechanism is high, the operation is easy, and the imaging range of the camera can be expanded vertically and horizontally, and the imaging range is appropriately secured.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a pan / tilt mechanism for a television doorphone according to the present invention will be described below in detail with reference to the drawings. As shown in FIG. 1, in the pan / tilt mechanism for a TV door phone according to the present invention, a camera 1 with a CCD element used as a child device of a TV door phone that images a visitor and displays an image on a TV screen.
A cylindrical prism 4 that deflects light 3 for imaging a visitor and enters the lens 2 of the camera 1 on the front surface of the lens 2
Wheels 6a and 7a as a prism rotation driving mechanism for rotating the cylindrical prisms 4a and 5f on the cylindrical side surfaces of the cylindrical prisms 4a and 5a, and the driving motor 8a. , 9a are provided.

Light 3 incident on the lens 2 of the camera 1
Is first polarized by the prism 4a and then also polarized by the prism 5a and passes through the lens 2 of the camera 1.
Then, the light is incident on and is output as an image electric signal via the CCD element. As shown in FIG. 2, the polarization angle at this time is determined by the angle θ formed by the prism surfaces 4e and 4f of the cylindrical prism 4a and / or the angle θ formed by the prism surfaces 5e and 5f of the cylindrical prism 5a. As the material of the cylindrical prisms 4a, 5a, optical glass or optical engineering plastic is suitable.

Unlike the conventional pan-tilt mechanism in which the camera itself swivels vertically and horizontally, the camera itself does not swivel and the lens of the camera 1 moves the image vertically and horizontally in the pan / tilt mechanism for a TV door phone according to the present invention. This is performed by changing the polarization direction due to the rotation of the cylindrical prisms 4a and 5a arranged on the front surface of the No. 2. The principle of moving the image vertically and horizontally is as follows.

As shown in FIG. 3, a cylindrical prism 4a,
When 5a is at a position 180 ° symmetrical to each other with respect to the sliding contact surfaces 4f and 5f, the incident light advances as shown by an arrow M, and the image in front of the camera is incident on the camera. As shown in FIG. 4, when the cylindrical prisms 4a and 5a are vertically symmetrical with respect to the sliding contact surfaces 4f and 5f, the incident light travels as indicated by an arrow N and is on the right front side of the camera. The image is incident on the camera.

As shown in, the cylindrical prisms 4a, 5
By changing the combination of a by rotating the wheels 6a and 7a as the prism rotation drive mechanism, it is possible to cope with pan-tilt up, down, left and right. The relationship between the rotation directions of the cylindrical prisms 4a and 5a by the prism rotation drive mechanism and the field of view is as shown in FIG. 5, and in order to image the direction A, the combination of the cylindrical prisms 4a and 5a is shown in FIG. As is, two cylindrical prisms 4a,
After rotating 5a by 90 ° in the X or Y direction, the cylindrical prism 5a is rotated by 90 ° in the X direction and the cylindrical prism 4a is rotated by 90 ° in the Y direction.

To image in the direction a, the two cylindrical prisms 4a and 5a are rotated 90 ° in the X or Y direction with the combination of the cylindrical prisms 4a and 5a shown in FIG. The prism 5a is rotated 90 ° in the Y direction and the cylindrical prism 4a is rotated 90 ° in the X direction. To image the c direction, the cylindrical prism 5a is rotated 90 ° in the X direction and the cylindrical prism 4a is rotated 90 ° in the Y direction.

To image the direction D, the cylindrical prism 5a is rotated 90 ° in the Y direction and the cylindrical prism 4a is rotated 90 ° in the X direction. To image the oblique direction at 45 °, the two cylindrical prisms 4a and 5a are rotated by 45 ° in the X or Y direction with the combination of the cylindrical prisms 4a and 5a shown in FIG. The mold prism 5a is rotated 90 ° in the X direction and the cylindrical prism 4a is rotated 90 ° in the Y direction.

[0017]

As is apparent from the above embodiments, according to the pan / tilt mechanism for a TV door phone of the present invention, the pan / tilt mechanism is downsized, the mechanism is simple, the accuracy of the mechanism is high, and the operation is easy. In addition, the image pickup range of the camera can be expanded vertically and horizontally, and the image pickup range is appropriately secured.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an embodiment of a pan / tilt mechanism for a television doorphone according to the present invention.

FIG. 2 is a diagram illustrating a polarization angle of the cylindrical prism.

FIG. 3 is a diagram illustrating polarization directions of combinations of cylindrical prisms.

FIG. 4 is a diagram illustrating a polarization direction depending on a combination of cylindrical prisms.

FIG. 5 is a diagram illustrating an image pickup direction by combining a cylindrical prism of the pan / tilt mechanism for a TV door phone according to the present invention.

6A and 6B are views for explaining a conventional pan / tilt mechanism for an electric TV intercom, in which FIG. 6A is an overall perspective view and FIG. 6B is a partially enlarged sectional view thereof.

7A and 7B are diagrams illustrating a conventional pan / tilt mechanism for a manual TV door phone, in which FIG. 7A is an overall perspective view and FIG. 7B is a sectional view thereof.

[Explanation of symbols]

 1 ... Camera with CCD element 2 ... Lens 3, M, N ... Light 4a, 5a ... Cylindrical prism 4f, 5f ... Prism surface 6a, 7a ... Wheel (prism rotation driving mechanism) 8a, 9a ... Driving motor (prism rotation) Drive mechanism) X, Y ... Rotation direction of cylindrical prism

Claims (1)

(57) [Claims] 1. A light for imaging the visitor is deflected in front of a lens (2) of a camera (1) used in a child device of a TV intercom that images the visitor and displays an image on a TV screen. Two cylindrical prisms (4a, 5a) having a substantially cylindrical column-shaped light entrance / exit surface for allowing light to enter the lens of the camera are provided with prism surfaces (4f, 4f, which are orthogonal to the columnar axis direction). 5f) are arranged in sliding contact with each other, and prism rotation drive mechanisms (6a, 9a, 7a, 8) for rotating each cylindrical prism on each cylindrical side surface of each cylindrical prism.
A pan / tilt mechanism for a TV door phone, characterized in that by providing a), the two cylindrical prisms are relatively rotated to expand the imaging range of the camera vertically and horizontally.