Space-time light modulator

FIELD: physics.

SUBSTANCE: proposed light modulator comprises encased base made from solid-phase electrooptical material with surface optically processed in plane perpendicular to incident light radiation. Said base represents light cells arranged in regular structure operating on transverse electrooptical effect. Note here that electrodes with electric contact terminals stay in contact with said base. Through electrodes are arranged in said base so that the latter represents regular unidimensional matrix of light cells separated by electrodes. Electrodes are protected along their length in two planes subjected to light radiation. Said protection represents mirror strips applied onto translucent windows opposite said electrodes.

EFFECT: higher reliability and stability, smaller area of opaque zones.

7 cl, 1 dwg

The invention relates to the field of quantum electronics, specifically, to optical modulators radiation, and can be used in laser ranging, in the guidance systems of radiation.

In the framework of the application as spatial temporal light modulator element is considered performing phase modulation of the light beam.

Known space-time light modulator (PWM) (Ali and other Spatial light modulators. - M,: Radio and communications, 1987, p.63). The modulator is a base of the electro-optic material with light cells placed between the control electrodes regularly arranged on the surface of the base.

The disadvantage of this modulator is that due to the small thickness of the electro-optic material and the location of the electrodes on the surface of the base there is a possibility of burn-in electrodes due to light ablation or surface breakdown. The small thickness of the electro-optic material base requires submission of a high control voltage to set the respective phase difference between the longitudinal and transverse components of the light wave, also leading to surface breakdown.

Known PWMs (patent RU 02040090, 20.07.95), which is a base of solid state electro-optical material with optical treated surface is rnostly in the plane orthogonal to the incident laser radiation. The base is a one-dimensional matrix of light cells of rectangular shape, is placed between the control electrodes embedded in the base material, and working on the transverse electro-optic effect. Conclusions electrodes connected to the circuit Board for supplying control voltages. The whole structure is placed in the case.

In this modulator, there is a likelihood of burnout electrodes and requires a high control voltage, in addition, a significant width of the electrodes leads to the formation of opaque to radiation working areas of the cell because of the existence of the shaded electrodes zones.

The challenge is to develop a reliable and energy-efficient light modulator.

The technical result consists in increasing the reliability of the modulator by reducing the likelihood of electrical breakdown between the electrodes, increasing the climate resilience of the modulator and in the reduction of the area of the opaque areas of the modulator; in addition, the decrease of the control voltage by increasing the homogeneity of the electric field between the electrodes in the volume of electro-optic material.

This technical result is achievable due to the fact that in contrast to the known space-time light modulator, terasawa installed in the housing base of the solid state electro-optical material with optical surface in the plane perpendicular to the incident light radiation, the base is a located in a one-dimensional regular structure length cell operating on a transverse electro-optic effect, with the base contact of the electrodes with the conclusions of the electrical contacts, in the proposed modulator in the base material are periodically through the electrodes so that the base is a regular matrix of light cells, separated by electrodes.

The body of the modulator can be made watertight with transparent Windows for the passage of radiation, to be sealed connectors for supplying control voltages to the electrodes and filled elektroprogram gas.

In particular the performance of the modulator can be performed as follows: the base is made of enlightened electro-optic ceramics, as electrodes used metal foil, the base is mounted on the enlightened substrate of transparent isotropic optical material, the electrodes are protected along the entire length in two planes, is exposed to light radiation, protection made in the form of mirror strips deposited on a transparent window in front of the electrodes or the electrodes.

In addition, the modulator conclusions the electrical contacts of the electrodes can be isolated.

The thickness of the base of the modulator can be the ü selected from the conditions of its comparability with the cross-sectional dimension of the light cell.

The presence of a base modulator through-electrodes are periodically arranged so that the base is a regular one-dimensional matrix of light cells, separated by electrodes allows to reduce the probability of breakdown by increasing the working width of the electrode.

In addition, the location of the modulator in a sealed enclosure with Windows filled elektroprogram gas such as sulfur hexafluoride, if the case is sealed electrical connectors will eliminate the possibility of electrical breakdown when the control voltage.

When performing electrodes in the form of foils, the thickness of the electrodes can be significantly reduced compared to the thickness of the electrodes in the prototype that will reduce the size opaque to radiation sections of the working cell.

Placing the modulator in a sealed enclosure will protect it from the effects of climatic factors.

Protection of electrodes from the light radiation will avoid damage to the electrodes radiation due to light ablation.

The choice of the geometry of the base, on the basis of the comparability of its thickness with transverse cell size, can achieve high uniformity of the electric field in a specific cell due to its location in a flat electrical capacitor formed by the neighboring electrodes. P and it is possible to increase the cell size in the propagation direction of the radiation and the decrease of the control voltage of the modulator, since the control voltage is inversely proportional to the optical path of radiation in the electro-optical material.

The drawing schematically shows a modulator (top view).

The modulator is a base (1) of the electro-optical ceramics. Technologically base is an integral and dialed in the form of regular patterns of light cells (2) of rectangular shape in cross section perpendicular to the incident light radiation, between which electrodes are in the form of a foil (through-electrodes in the body of the base (3). The base is mounted on the substrate (4) of fused silica as its holder in the housing. The base electrodes placed in a sealed housing (5) with Windows of glass K8 (6) coated with opposite electrodes on both sides mirrored (7). Housing filled with insulating gas at a pressure of 1.1 to 2 ATM. Electrodes through isolated findings (8) contacts associated with source control (9).

When connecting the source control (9) via pins (8) on the electrodes (3) control voltage, to the selected light cell (2) there is a transverse electro-optic effect. At the output of the cell is formed phase modulated radiation. The radiation passes through a window (6). Further, the modulation of the polarization of the radiation is converted into amplitude with additional polarizers. Through this form is : the corresponding intensity distribution in the plane of the modulator, in the specific case of laser radiation.

Improvements in the modulator reduced the likelihood of electrical breakdown between the electrodes, and, in addition, the increase climate resilience of the modulator and the reduction of the area of the opaque areas of the modulator.

1. The spatio-temporal light modulator, including installed in the housing base made of solid electro-optical material with optical surface in the plane perpendicular to the incident light radiation, and is composed of light cells running on a transverse electro-optic effect, and the electrodes with the conclusions of electrical contacts, wherein the base material are periodically through the electrodes so that the base is a regular matrix of light cells separated electrodes, while protecting the electrodes from the light beam in two planes, is exposed to light radiation.

2. The modulator according to claim 1, characterized in that the casing is sealed, equipped with a hermetic electrical connectors for supplying control voltages to the electrodes and filled elektroprogram gas, and the body is made of a transparent window for passage of light radiation.

3. The modulator according to claim 1, characterized in that the findings from actrices contact electrodes are isolated.

4. The modulator according to claim 2, characterized in that the base is made of enlightened electro-optic ceramics, light cells have a rectangular shape in cross section perpendicular to the incident radiation, and as a cross-cutting electrodes used metal foil, and the base for installation in a housing mounted on a substrate of transparent isotropic optical material, and the housing filled with insulating gas.

5. The modulator according to claim 2 or 4, characterized in that the electrodes are protected from the directional radiation along the entire length.

6. The modulator according to claim 5, characterized in that the protection is made in the form of mirror strips deposited on a transparent window in front of the electrodes or the electrodes.

7. The modulator according to claim 1, characterized in that the thickness of the base is selected from the conditions of its comparability with the cross-sectional dimension of the light cells.