SK501172013U1 - Apparatus for controlling deflection of the laser beam using a diffractive structure - Google Patents

Abstract

The device for controlling the deflection of the laser beam by the diffractive structure consists of a diffractive structure formed by at least one optical diffractive element (MODE). The laser beam passing through the device is deflected from the original direction by an angle which is a function of the position and number of optical diffractive elements. The device can be used as an alternative to a galvanometric engine mirror system.

Description

Device for controlling laser beam deflection by diffractive structure.

Technical field

The device for controlling the deflection of the laser beam by means of a diffractive structure consists of at least one optical diffractive element (hereinafter ODE). In the basic arrangement, the device does not deflect the incident laser beam. Changing the position of the ODE relative to the axis of the laser beam results in the deflection of the incident laser beam by an appropriate angle.

BACKGROUND OF THE INVENTION

At present, scanning plane mirrors are used to control the deflection of the laser beam. The angle that the animal reflects the laser beam with the plane of the mirror is equal to the angle of incidence of the beam on the mirror. Rotating the mirror by means of a galvanometric motor causes the beam to be deflected. This method allows the laser beam to be deflected in the order of tens of kilobits per second at angles of 7 to 8 degrees. This speed decreases with larger deflections. Bundles with a larger radius require the use of larger mirrors. As the mirror surface increases, it is necessary to increase the mirror thickness to prevent mechanical bending and deformation of the reflected beam when the mirror is oscillated. Thus, larger mirrors are considerably heavier than smaller mirrors and thus allow the beam to deflect at a frequency several times lower than smaller mirrors. Even with the use of smaller mirrors, the entire device is relatively large and difficult to install in small electronic devices.

The essence of the technical solution

The principle of a method of deflecting a laser beam according to the invention consists in that the beam is deflected by passing through a diffractive structure composed of at least one optical diffractive element. In the basic arrangement, the structure does not deflect the bundle. At least one of the optical diffraction elements is mobile. When the position of the mobile optical diffraction element is changed relative to the axis of the incident laser beam, the incident beam is deflected. The magnitude of the angle and the plane in which the beam is deflected are determined by changing the position of the mobile optical diffractive element relative to the beam axis.

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If the laser beam is deflected by passing through a diffractive structure formed by a pair of optical diffractive elements of which at least one is a mobile optical diffractive element, the beam deflection angle is greater than when using a diffractive structure comprising only one optical diffractive element. By varying the position of the mobile optical diffraction element with respect to the beam axis, the incident beam is deflected. The magnitude of the angle and the plane in which the beam is deflected are determined by changing the position of the mobile optical diffractive element relative to the beam axis.

One possibility of constructing a diffractive structure that deflects a passing laser beam and consists of a pair of optical diffractive elements is to use one mobile optical diffractive element and one static diffractive element. By varying the position of the mobile optical diffraction element with respect to the beam axis, the incident beam is deflected. The magnitude of the angle and the plane in which the beam is deflected are determined by changing the position of the mobile optical diffractive element relative to the beam axis. The static optical diffraction element additionally deflects the beam deflected by the mobile optical diffraction element.

If the above-described diffractive structure comprising two optical diffractive elements consists of a pair of mobile diffractive elements, a deflection of the laser beam by a larger angle can be achieved than if one static and one mobile optical diffractive element of the same quality are used.

For deflecting the laser beam, it is advantageous to use a diffractive structure formed by two pairs of optical diffractive elements for deflecting simultaneously in two mutually perpendicular planes, one of the pairs of optical diffractive elements being rotated 90 ° relative to the other pair about the axis of the device.

The main advantage of the present invention is that the laser beam deflection control device composed of at least one mobile optical diffractive element makes it possible to deflect the laser beam with

ο · Speed and frequency several times higher than when using a scanning mirror with a galvanometric motor. The optical diffraction elements do not rotate during operation. Therefore, they do not undergo mechanical bending during operation and there is no need to increase their thickness as the surface of the optical diffractive element increases. Thus, as the surface of the optical diffractive element increases, the weight of the optical diffractive element increases more slowly compared to a galvanometrically controlled mirror. Therefore, the scanning frequency with the increasing surface of the optical diffraction element decreases more slowly compared to the galvanically controlled mirror. Since the optical diffraction elements do not rotate during operation, they require less operating space than the scanning mirror.

BRIEF DESCRIPTION OF THE DRAWINGS

In FIG. 1 shows a diffractive structure formed by one optical diffractive element which is displaced away from the home position.

In FIG. 2 shows a diffractive structure composed of two optical diffractive elements in a basic configuration.

Fig. 3 shows a diffractive structure composed of two optical diffractive elements. The mobile optical diffraction element MODE is displaced in a horizontal plane with respect to the static optical diffraction element SODE.

In FIG. 4 shows a diffractive structure composed of two optical diffractive elements. The mobile optical diffraction element MODE is displaced in a vertical plane relative to the static optical diffraction element SODE.

In FIG. 5 shows a diffractive structure composed of two mobile optical diffraction elements MODE. The two mobile diffractive elements are displaced in a horizontal plane with respect to the base position in opposite directions to each other.

EXAMPLES

The embodiment of FIG. 1 is a diffractive structure formed by a single optical diffractive element that is displaced in a horizontal plane away from a basic position indicated by a dotted line. The passing laser beam LZ is deflected by an angle od from the original direction.

The diffractive structure shown in FIG. 2 is composed of two optical diffraction elements in ι «· W>» ·

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basic layout. In this arrangement, the beam is not deflected when the laser beam passes through the diffractive structure.

The diffractive structure shown in FIG. 3 is composed of two optical diffraction elements. The mobile optical diffraction element MODE is displaced in a horizontal plane with respect to the static optical diffraction element SODE. Scroll options are indicated by arrows. In this arrangement, when the laser beam LZ passes through the structure, it is deflected in the horizontal plane. The deflection of the beam is expressed by the angle α. The magnitude of the angle α is a function of the position of the mobile optical diffraction element MODE in the horizontal plane.

In FIG. 4 shows a diffractive structure composed of two optical diffractive elements. The mobile optical diffraction element MODE is displaced in a vertical plane relative to the static optical diffraction element SODE. Scroll options are indicated by arrows. In this arrangement, when the laser beam LZ passes through the structure, it is deflected in the vertical plane. The deflection of the beam is expressed by the angle θ. Angle size /? is a function of the position of the mobile optical diffraction element MÓDE in the vertical plane.

The embodiment shown in FIG. 5 shows a diffractive structure composed of two mobile optical diffractive elements MÓDE. The two optical diffraction elements are displaced in the horizontal plane in opposite directions to each other with respect to the basic position indicated by the dotted line. In this arrangement, when the laser beam LZ passes through the structure, it is deflected in the horizontal plane. The beam deflection is expressed by the angle y. The magnitude of the angle y is a function of the positions of the two mobile optical diffraction elements MODE in the horizontal plane.

By arranging the diffractive structures shown in FIG. 3 and FIG. 4, a device capable of simultaneously controlling the deflection of the passing laser beam in the horizontal and vertical planes is formed in series.

The movement of the optical diffraction element may be provided by a piezoelectric actuator. The piezoelectric actuator makes it possible to change the position of the component to which it is attached at a frequency several times higher than the galvanic motor.

Industrial usability

Device for controlling laser beam deflection by a diffractive structure composed of:

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of two ODEs or two of their ODEs can be used in any laser device as an alternative to a galvanometric motor-controlled scanning mirror system. The system can be used in laser projectors for lasershows, in the projection of advertising signs, in laser video projectors, in welding and engraving equipment, in the display of warning and information signs in public areas and in many other applications.

Claims (5)

A laser beam deflection control device comprising a diffractive structure comprising at least one mobile optical diffractive element (MODE) for deflecting a laser beam passing therethrough by changing the position of the mobile optical diffractive element (MODE) relative to the beam axis with an angle size and beam deflection planes determined by changing the position of the mobile optical diffraction element (MODE) with respect to the beam axis. Apparatus according to claim 1, characterized in that it consists of a diffractive structure comprising a pair of optical diffractive elements, at least one of which is a mobile optical diffractive element (MODE) for deflecting a laser beam passing therethrough by repositioning the mobile optical diffractive element (MODE) with respect to a beam axis with an angle magnitude and a beam deflection plane determined by changing the position of the mobile optical diffraction element (MODE) with respect to the beam axis. Apparatus according to claim 2, characterized in that it consists of a diffractive structure comprising a pair of optical diffractive elements consisting of two mobile optical diffractive elements (MODE). Apparatus according to claim 2, characterized in that it consists of a diffractive structure comprising a pair of optical diffractive elements consisting of one mobile optical diffractive element (MODE) and one static optical diffractive element (SODE). Device according to one of Claims 1 to 4, characterized in that it consists of a diffractive structure comprising two pairs of optical diffractive elements for deflecting the laser beam simultaneously in two perpendicular planes, one of the pairs of optical diffractive elements (ODE) being rotated 90 ° relative to the second pair about the axis of the device.