JPS6076726A - Disc driver of television camera - Google Patents

Abstract

PURPOSE:To reduce the size and cost of a television camera by provding a bar code on a filter disc and reading the bar code with one position detecting sensor. CONSTITUTION:Four sheets of filters 2a-2d such as color temp. filters or ND filters are concentrically provided on a filter disc 1 and bar codes 9a-9d are provided so as to correspond therewith. When an operator operates a button to select the desired filter of the filters 2a-2d, a signal processing circuit 11 compares the filter selection signal and the signal for the current position of the disc 1 read with a sensor 6 and calculates a rotating direction and the rotating amt. of the disc 1 until the desired filter arrives at the prescribed position in the shortest time. A motor 3 is driven in accordance with the result of the calculation to select the desired filter. Then just one position detecting sensor is required and the device is effective in reducing the size of the television camera.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disk drive for a television camera, and more particularly to a filter disk drive within a body of a television camera and an extender drive within a lens of a television camera.

Generally, in the main body of a television camera, a filter disk having a plurality of different optical filters arranged on a concentric circle is rotated in order to correct the color temperature and light intensity of the subject.
Select a desired filter as appropriate and place it on the optical path of the television camera. Also, inside the lens of a TV camera,
In order to zoom the subject, in addition to moving lenses or lens groups called variators and compensators,
Rotate the extender, which has multiple lenses with different magnifications on concentric circles, between the convencator and the relay lens,
Select a lens with the desired magnification as appropriate.

Conventionally, in this type of device, as illustrated in FIG. 1, a filter disk 1 has four filters 23 to 2d concentrically arranged in a color temperature filter, an ND filter, or two filters bonded together. Then, the filter is rotated by a predetermined angle by the motor 3, and a desired filter is selected. In this case, the positional information of the filters 2a to 2d can be obtained by rotating the potentiometer 5 through a gear 4 meshed with a gear (not shown) provided on the outside of the disk 1, and reading the resistance value of the potentiometer 5. ing.

Another method is to use a filter 2 as shown in FIG.
There is a method in which sensor markers 8a to 8d are provided on the disk 1 corresponding to the markers 3 to 2d and read by optical sensors 6a to 6C. In this case, if one disk has four filters, one optical sensor is provided to detect the stop position of the disk, and two optical sensors are provided to discriminate between the four filters.

However, in the device of Figure 1, the gear ratio is large because the diameter of the potentiometer shaft is much smaller than the diameter of the filter disc, and therefore many gears are required to match one revolution of the disc to one revolution of the potentiometer. and requires a large volume within the television camera. Further, the apparatus shown in FIG. 2 also requires a plurality of sensors, which is disadvantageous in reducing the size and cost of the I''V camera.

In view of the drawbacks of the conventional example described above, the purpose of the misfiring ψJ is to provide a disk drive device that has a bar code on the filter disk and reads the bar code with one sensor, thereby reducing the size of the television camera. It is also possible to reduce the number of parts.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a configuration diagram of an embodiment of the present invention, in which the filter disk 1 includes four filters such as a color temperature filter or an ND filter.
The filters 2a to 2d are arranged concentrically. Normally, two disks, a color temperature filter disk and an ND filter disk, are used in a television camera, and each filter is selected independently. Sometimes it is used as a single disc.

Barcodes 9a to 9d as shown in FIG. 3 are provided on the disk 1 to correspond to the filters 2a to 2d, respectively, and the barcodes 9a to 9d each have a unique filter identification as shown in FIG. barcode section], Oa +
10 C and filter stop detection barcode section 10! ]. Note that the barcode section 10a and 1. The OCs are arranged in a symmetrical arrangement.The TV camera body (not shown) includes a disk drive motor 3 and barcodes 9a to 9a.
A sensor mount 7 with one optical sensor 6 for reading 9d is fixed.

In the above configuration, when the operator operates a button on the operation panel (not shown) to select a desired filter from among the filters 2a to 2d, the signal processing circuit 11 receives the filter selection signal as shown in FIG. The current position of the disk read by the sensor 6 is compared with the signal of the current position of the disk, and the direction and amount of rotation of the disk 10 is calculated until the desired filter reaches a predetermined position (on the optical path of the television camera) in the shortest possible time. The motor drive circuit 12 drives the motor 3 based on the calculation result, and thus a desired filter is selected.

Note that a microcomputer is built into the television camera for automatic adjustment of various functions, and if this microcomputer shares the signal processing circuit 11 of the above embodiment, the television camera can be further miniaturized and cost reduced. can be realized.

In the above embodiment, an optical sensor was used as a means for detecting the barcode, but a magnetic sensor may also be used, and the barcode does not have to be symmetrical unless the minimum time for rotating the disk is taken into account (' −.

Of course, the present invention can also be applied to driving an extender used in a television camera lens.

As explained above, barcodes are used to detect the position of the filter disk, so only one position detection sensor is required (
This is effective in reducing the size of television cameras, and the number of parts is reduced, which is effective in reducing costs.

[Brief explanation of drawings]

1 and 2 are block diagrams of a conventional filter disk drive device for a television camera, FIG. 3 is a block diagram of an embodiment of the present invention, and FIG. 4 is a block diagram of the bar code shown in FIG. The front view, FIG. 5, is a block diagram of the electrical system that drives the device of FIG. 1... Filter disk 2a + 2b r 2C+ 2d... Filter 6
. . . Optical sensors 9a, 9b, 9c, 9d---Barcodes Fig. 1 Fig. 2 10alOblOc Fig. 4 1 Fig. 5

Claims (1)

[Claims] In a disc drive device for a television camera that rotates a disc on which a plurality of optical systems are provided concentrically and selects and positions one of the optical systems, a bar code corresponding to the optical system is placed on the disc. What is claimed is: 1. A disk drive device for a television camera, characterized in that said barcode is provided with a detection means for reading said barcode.