SU724094A3 - Apparatus for converting optical images - Google Patents

Abstract

1445119 Television RESEARCH CORP 26 Sept 1973 [29 Dec 1973] 45011/72 Heading H4F A device for converting an optical image into electrical signals which are spatial Fourier transform representations of the optical image uses a medium having an electrical property which varies as a function of an incident optical image and strain disturbances, the electrical property being measured as a plurality of varying strain disturbances are sequentially caused in the medium to provide a like plurality of electrical signals, each representing one term in the Fourier transform. In one embodiment, Fig. 5, for a one-dimensional image projected by a projector 18 the medium is formed by a film 12 on a substrate 10, surface acoustical waves being generated by a transducer 20 fed by a sweep frequency generator 24. A constant voltage from source 28 is applied between electrical contacts, 14, 16, changes in the conductivity of the film 12 being detected by a detector 34 which also receives a frequency-related input from generator 24. Several of the devices of Fig. 5 may be connected in parallel (Fig. 6, not shown) for two-dimensional images, using interdigitated tooth-like contacts. In an alternative embodiment voltage changes across a semi-conductor or metal bar (36, Fig. 7, not shown) receiving a onedimensional image and being subjected to bulk wave vibrations are detected. In a further embodiment, Fig. 8, for twodimensional images an image is projected by a projector 70 through a substrate 56 vibrated by transducers 72 to a photo-cathode film 58, emitted electrons being collected at 60, the voltage across a resistor 64 being measured to derive the output signals. In an alternative embodiment the image is projected on a selected area of a substrate (56, Fig. 9, not shown) vibrated by two transducers. The vibrating medium in each of the above devices may vibrate at a fundamental frequency and simultaneously at one or more harmonics, the signals relating to these different frequency being separated by electronic filters (106a- 106c, Fig. 11, not shown). For deriving signals from a colour image three devices (114a-114c, Fig. 12, not shown) may be used, each receiving a different primary colour image component. To reproduce an image from the derived signals the signals are fed to transducers (92, 94, Fig. 10, not shown) coupled to an elasto-optical plate (88) positioned between crossed polarizers, light being shone on one end of this assembly, the plate causing local changes in the angle of polarization of light passing through it. The light transmitted by the assembly can be stored, as a signal, in an acoustic delay line which adds up the Fourier components; an electronic shutter or flash tube can then illuminate the sound wave complex to derive a total optical image.

Description

The invention relates to automation and computer technology, in particular, to devices for converting images into electrical signals. ·.

A device is known comprising an image projection unit optically coupled to an image conversion unit made in a vice sensitive surface (1).

This device is characterized by low accuracy of image conversion.

Closest to the invention relates to a device containing a phase detector, the input of which is connected to a power supply, an image projection unit and a sound oscillation generator [2].

The aim of the invention is to improve the accuracy of the device.

This is achieved by the fact that it contains a block of formation of deformation vibrations, the inputs of which are connected to a generator, sound vibrations, to a power supply unit and are optically coupled to an image projection unit, and the output is connected to one input of a phase detector, the other input of which is connected to a sound vibration generator, as well as the fact that the deformation vibration generation unit contains a substrate made in the form of a quartz rod, on the surface of which a film of light-conducting semiconductor and metallic contacts.

The drawing shows a block diagram of a device.

The device includes a generator of sound vibrations (frequencies) 1, a deformation vibration generation unit 2, comprising a substrate 3 made in the form of a quartz rod, on the upper surface of which a film 4 of a light-conducting semiconductor having its own conductivity and metal contacts 5, made, for example, is applied in the form of aluminum strips, a power supply 6, a resistor 7, a phase detector 8, a block 9 for projecting (optical) images and a sound-absorbing block 10.

The device operates as follows.

Block 9 projects an image onto the surface of the film 4. Generator 1 through block 2 generates a surface acoustic wave distributed from block 3 724094 ka 2 to block 10. The potential difference between the metal contacts 5 from block 6 during propagation of the surface acoustic wave changes and is recorded on the resistor 7 from where the changing voltage is supplied to the phase detector 8, where the voltage of the reference sound frequency from the generator 1 is also supplied.

At each frequency of sound vibrations, the conductivity of the film, measured on resistor 7, is a condition under which the Fourier frequency sequences are analogous to the image projected by block 9 onto film 4. ’

The introduction of new blocks and new structural connections can significantly improve the accuracy of the device.

Claims (2)

The claims 20 1. A device for converting optical images, comprising a phase detector, the input of which is connected to a power supply unit, an image projection unit and an acoustic oscillation generator, characterized in that, in order to improve the accuracy of the device, it comprises a deformation vibration generation unit, the inputs of which are connected to the sound oscillator, to the power supply and are optically connected to the image projection unit, and the output is connected to one input of the phase detector, the other input of which is connected to the sound generator kovy fluctuations. 2. The device according to π. 1, characterized in that the deformation vibration generation unit comprises a substrate made in the form of a quartz rod, on the surface of which a film of a light-conducting semiconductor and metal contacts are successively applied.