DE2033931B2 - LIGHT DEFLECTOR - Google Patents

Description

3. Apparatus according to claim 2, characterized in that 15
indicates that each of the diffraction grating arrangements (B ₁ Β ') arranged one behind the other

for directing passage through them. The invention relates to a device

the light beam (L) in only one coordinate with a lattice structure to deflect a coherent

direction is measured ao rent light beam by diffraction.

4. Device according to one of the preceding light beams let Jch for example by the claims, characterized in that the mechanical arrangements with rotating mirrors abStruktur of the diffraction grating (Gi) in the sense of a steer. With this, however, only simple or multi-spatial intensity modulation of the deflections periodic _{by them f ac b are possible.} In addition, the light beam passing through (LJ complex - the speed of deflection by the mecha-shaped system is very limited here

5. Device according to one of the preceding significantly higher deflection speeds lasden speech, characterized in that the _{sen s} j _cn using electro-optical methods bring about individual diffraction gratings (GO side by side. They are based on the controllability of a translucent PUtte (P, P ') ₃₀ or an index of refraction in the electro-optical crystals are arranged in-Fi'm. game, a KDP crystal. The in such a

6. Apparatus according to claim 5, characterized in that the control voltage to be applied crystal requires that the _{values arranged next to one another are} undesirably high, since this effect is only neten diffraction grating (Gi) on the translucent _very U ^ _{n -} the number also remains here auflöslässigen the plate (P, P ') in the manner of an acoustic cash ₃₅ directions at reasonable cost beplattenrille in its entirety a spiral path limits. In addition, the optical malformations and the relative movement of the light in _the crystals used lead to phase errors.
Beam (L) to the diffraction grating through rota- _In more recent times, light deflections have gained importance of the plate with simultaneous radial ^ g, in which the light deflection of a movement of the light beam takes place 40 coherent light beam with the help of an ultra-

7. Apparatus according to claim 5, characterized overall sound waves phase grating generated brought indicates that the adjacent angeord- ^ _n J light deflection devices of this type Neten diffraction grating (Gt) on the VISIBLE LIGHT _{use the SO} g _en annten acousto-optics from. The permeable plate (P) form concentric rings, medium, preferably a liquid, which furthermore _{stimulates the relative movement of the light beam 45 to an} ultrasonic generator to standing waves (L) to the diffraction grating by rotating the _{> stdlt for the} passing light beam plate, and in that the light beam to input _a phase grating is, the _frequency by the choice of Frestellung to a predetermined ring-diffraction can be _{changed, the} ultrasonic wave grid arrangement in the radial direction to the _{plate, and thus the} deflection of light passing is 50 light beam adjustable. Through two and more in a row

8. Device according to one of claims 1 arranged light deflection devices of this type, up to 4, characterized in that dieBeugungs- _{also called} ultrasonic cells, a light grid (Gi) can be side by side in strip form, _stran i with suitable dimensioning and arrangement of possibly in several Arranged one on top of the other, deflect ultrasound cells in two coordinate directions in parallel strips on a fixed 55 as desired.

the or transportable film are arranged. The invention is based on the object for

9. The device according to one of the preceding, the deflection of a coherent light beam one of the claims, characterized in that the further solution to indicate that with a simple design grating structure of the individual diffraction grating (G /) device also enables very complicated deflection processes has a sinusoidal amplitude distribution. 60 light and also a spatial module

10. Device according to one of the previous lation of the deflected light beam

the claims, characterized in that the This object is characterized according to the invention

Grating structure of the diffraction grating (G /) three-resolved that two or more fixed diffraction grating

is dimensional. are arranged next to each other and

11. Device according to one of the preceding 65 transmission grid arrangements and the light beam relative the claims, characterized in that they are designed to be movable relative to one another.

the control signal zero of this in its Rieh- The invention is the essential finding

dependent deflected light beam is based on the fact that arbitrarily complicated deflection

thereby realizing the paths of a coherent beam of light allow the deflection program to be set in a large number of fixed diffraction gratings lets that timed in a predetermined order

UUlVU UIV UILlvini / iidiuu ». ~. ~ - _o - _o

of the diffraction grating thus results in a resolution Δφ of the diffraction angle ψ

In the area of small angles (sin φ ä number of resolvable directions

B. D.

(Π)

applies to the

(III)

As equation (III) shows, one has

Sional diffraction grating of this type it is possible with the help of the so-called Bragg reflection in addition still suppress a first-order ray. In addition to the undeflected light beam LO

successively exposed to the incident light beam 5 then only the deflected light is produced. beam L11. This fact is by representation

Although it is through the reference "Applied of the second deflected light beam L Lt first optics", Vol. 6, No. 9, Sept. 1967, pp. 531 to 534, the order indicated in broken lines, known with the help of a moving hologram that the deflection direction is determined by the direction of the

to deflect the incident reference wave in that io grating lines determine the amount of deflection the direction of the reconstructed object wave in Ab- by the grating constant. With a given width B, the relative position of the hologram is dependent
to the source of the reference beam is changed. Indeed
In contrast to the subject matter of the invention, only single or multiple 15
perform periodic distractions.

Which represent a distraction program in its entirety Diffraction grating or diffraction grating arrangements according to the invention can by suitable Design of the lattice structures additionally in the sense of ao a spatial intensity modulation of the light beam passing through them be.

In a preferred embodiment according to the ",.

Invention, the individual diffraction gratings are adjacent to 35 grating constants D = 2 ;. = 1 μΐη a resolution of one another on a translucent plate or of 10 ⁶ spatial directions in a diffraction grating a film. the size of a square millimeter.

For some applications it should be advantageous through the suitable choice of the structure of the The diffraction gratings or the diffraction grating arranging the diffraction grating can provide additional information a 30 mation can be expressed in the direction of the light beam. This additional Infor laser amplifier With a high aperture, preferably mation can with the help of an influence on the

Contrast consist in a spatial intensity modulation of the deflected light beam. Also can through a suitable choice of the grating structure, the focusing of the deflected light beam in a predetermined Distance can be achieved.

Diffraction grating of the type mentioned, including sinusoidal grating, can be caused by the interference of two plane waves, for example in the emulsion of a

Fig. 1 is a schematic representation of a 40 photo plate to be generated. It makes sense to use the a fixed lattice of diffracted light beam, to fix the position of one beam and the other

Pivot beam depending on the desired grid structure. Other grid shapes are created in a corresponding manner by superimposing spherical waves in a +5 general form. In addition to photographic layers, light-sensitive crystals, chromophores, etc., are created by superimposing a constant reference wave with a variable object wave to obtain fixed diffraction gratings in the desired structure in a diagram with the path w.
carried blackening density α of the grating lines - Sometimes it can be used for the desired deflection

interpreted The perpendicular to the grating plane of the diffraction of a light beam make sense, two or more diffraction grids G incident coherent light beam L diffraction grating arrangements in front of one another will be seen in a plane according to known laws. The right to the lattice direction is deviated by the angle φ in a particularly clear manner. 55 circumstances in this case by the fact that each of the

to arrange a traveling field amplifier. The high aperture of the laser amplifier ensures one of the Deflection angle of the light beam independent gain.

Using the exemplary embodiments shown in the drawing the invention is to be explained in more detail below. In the drawing means

2 shows a first embodiment according to the invention,

3 shows a second embodiment according to the invention.

F i g. 1 shows a diffraction grating G, specifically a line grating with a sinusoidal amplitude distribution. The sinusoidal amplitude distribution of the line grating is shown below the diffraction grating G

The sine of this angle results in sin φ = Z -

(D

diffraction grating arrangements arranged one behind the other for a deflection of the light beam passing through them in only one coordinate direction is measured.

As has already been mentioned, in the invention assumed to bring about the temporal movement of a light beam in that a Plurality or multiplicity of individual diffraction gratings in a predetermined order over time

with the integer Z = 1, 2, 3. . ., the light wavelength λ and the lattice constant D, With the in FIG. 1 assumed sinusoidal amplitude distribution of the grating structure also arise

undeflected light beam LO in the order zero 63 successively exposed to the incident light beam only the two deflected light beams L11 and become.

L 12 first order. In this case, Z is therefore in both the first embodiment shown in FIG.

Equation (I) ± 1. When using a three-dimensional form, the diffraction gratings are in a circle on one

5 6

transparent plate P arranged. The diffraction windows are arranged on a plate P '. In this grating arrangement B , concentric rings are guide example, the plate P 'is fixed, and the light beam emanating from the laser La with respect to the axis of rotation of the plate P is represented by more than one periodic deflection based on the scanning type for the sake of clarity . As a result of the rotation of the plate P, the light beam L generated by a television image along the strip-shaped laser La successively falls on the diffraction grating arrangement B ' on the plate P' on the beu leads arranged one behind the other in the ring. The deflected light beam L11 generates a diffraction grating of the diffraction grating arrangement B. Currency to the stored Ablenkprogramm on the end of the undeflected light beam LO passes more or less komplibildungsebcne E in the exhaust image plane E, the deflected light io ed track. The multiply periodic Ablen-Lichtstrahl LIl imaged on the plane E and the light beam L is reflected with the help of two writes here, as shown for example, a mirror Sp 1 and Sp 2, which are perpendicular to each other eight. The axes of rotation A 1 and A 2 arranged in the ring on the plate P are rotatable. Here, diffraction grating Gf of the diffraction grating arrangement B If the rotational position of the mirror Sp 1 is correct, they can be seen in the enlarged section V. The 15 strip-shaped diffraction gratings Gi to be illuminated border one another here without a transition, and the mirror Sp 2 adjoins the movement of the one another. If necessary, they can also be designed in such a way that the light beam and the diffraction grating arrangement B ' are continuously transitions between two successive diffraction gratings G / before light beam and diffraction grating arrangement B'. As shown in the broken line in ao, the plate V can also be seen relative to an image plane E , a fixed light beam is moved, 'in this the structure of the successive case in the ring, the plate P' expediently consists of a diffraction grating Gi dimensioned in such a way that the deflected film tape, on which in the form of a strip, possibly in a light beam in the area of the junction of the eight, is more sharply focused than in the area of the arches. The light beam L emanating from the laser La is scattered across the net. For some applications, in contrast to this case, in the mirror Sp which can be rotated about the axis A ', several plates P are reflected. In fen-shaped diffraction grating arrangements, the mirror Sp enables, depending on its rotational position, a radial displacement of the light beam L by several fixed light beams. In this way it is illuminated.

possible, the light beam on one of the other, not As shown in Fig. 2, does not go off

The light beam LO as it passes through the, also shown concentric rings

! end diffraction grating arrangements. Plate P past the imaging plane E. Development

Instead of concentric rings, the same can be said of a diffraction grating, possibly arranged next to one another, on which the second light beam of the first order, as shown in FIG transparent plate P according to Fig. 2 in its Ge Fig. 1 is denoted by L12 In cases where Velvet in the manner of a record groove a spiral - the undeflected light beam LO disrupts it, it is purpose-built. To traverse this path it is moderate to have the control signal zero of this in its In this case it is necessary that the relative movement direction dependent deflected light beam a To assign the light beam to the diffraction grating by the beam direction, which corresponds to half the maximum rotation of the plate with a simultaneous radial deflection of the light beam. The unMovement of the light beam takes place. deflected light beam LO then does not overlap in any

In the case of the in FIG. 3 illustrated further embodiment trap with the deflected beam and can simply

Ring shapes according to the invention are those which are covered by a panel. At this

The diffraction method containing the deflection program also creates a symmetrical beam of light

Lattice arrangements B 'in parallel stripes of the first order are suppressed in the same way

1 sheet of drawings

Claims (2)

1 2 beam direction is assigned, which corresponds to half the patent claims: maximum deflection of the light beam and that the when passing through a Beu- 1. Device with a lattice structure for the transmission lattice existing undeflected partial beam Deflection of a coherent light beam through s is covered by a diaphragm Diffraction, characterized in that j 2. device according to one of the preceding two or more fixed diffraction gratings (Gi) besides the claims, characterized in that the are arranged with each other and here the diffraction gratings (Gi) or diffraction grating arrangement supply grid array (B, B ¹⁾ and the light beam voltages (B, B ^ in the beam direction of the light beam (L) relative to each other are movable. io (L) is a laser amplifier with a high aperture, upstream 2. Apparatus according to claim 1, characterized in that a traveling field amplifier, according to the invention, that there is two or more diffraction grating ter arrangements (B, B ') are arranged one behind the other.