CN103499848B - Laser micro thruster optical system and installation method thereof - Google Patents

Abstract

The invention belongs to the field of optics, and particularly relates to an optical system of a laser micro thruster and an installation method thereof, which are mainly used for developing the laser micro thruster in an attitude adjustment system of a space micro satellite. The laser micro thruster optical system comprises a semiconductor laser, a diffraction element high-order aspheric surface micro lens array and a target zone, wherein the semiconductor laser is arranged in the laser micro thruster; laser of the semiconductor laser forms a laser target surface through convergence of the high-order aspheric micro lens array of the diffraction element, the laser target surface is adjusted to coincide with a target zone during installation, and then the target zone is ablated to generate strong thrust. The invention has the advantages of volume, light weight, good focusing effect, simple debugging method, low energy consumption and the like.

Description

Optical system of laser micro thruster and installation method thereof

technical field

The invention belongs to the field of optics, and in particular relates to an optical system of a laser micro-thruster and an installation method thereof, which are mainly used in the development of a laser micro-thruster in an attitude adjustment system of an aerospace micro-satellite.

Background technique

Laser micro-thruster is a new type of micro-propulsion system, which is mainly used for position maintenance, attitude control, gravity compensation and orbit adjustment of micro-spacecraft. The laser micro-thruster optical system studied in this paper is mainly used for the integral focusing of high-energy laser. The optical system of laser micro-thrusters in the past is complex in structure and bulky, which cannot meet the miniaturization and low power consumption development requirements of aerospace micro-satellites. Therefore, it is necessary to study a miniaturized and lightweight optical system to meet the development requirements of microsatellites.

At present, the key to the performance of the laser micro-thruster prototype is focused on two points: increasing the power density of the spot and improving the performance of the target. Therefore, this requires that the laser micro-thruster optical system should have good focusing performance. There are mainly two types of thrust technology optical systems for aerospace vehicles. The first type: laser focus ablation is achieved through parabolic condensers; the second type: laser spot focus ablation is achieved through multi-lens groups. Although the above two methods have been widely used in practical engineering, there are still many defects. Although the first method produces strong thrust for aerospace vehicles, has a simple structure and is easy to implement, for aerospace micro-satellites, it first requires that the size of the micro-thruster be small, but adopting this method will make it The enlarged external dimensions cannot meet the miniaturization and lightweight requirements of MSI's overall design. The second method, although it has been put into use on many MSIs, the application of multi-mirror groups is not only complicated in the optical path, but also difficult to debug, and the focusing effect is always poor, resulting in a decrease in system energy efficiency. In order to meet the final use, the total input power can only be increased, thereby increasing the total power consumption of the system, which will greatly reduce the on-orbit service life of the MSI. Therefore, the above two methods are in urgent need of further improvement.

To sum up, considering that the research on this topic is the key technology for the development of aerospace micro-satellites, the successful research of this technology will indicate that the domestic aerospace micro-satellite micro-thrust technology has entered a new level. Therefore, carrying out the research on the optical system of the laser micro-thruster will play a role in promoting the development of my country's aerospace satellite industry.

Contents of the invention

In order to solve the problems in the background technology, the present invention provides a laser micro-thruster optical system and its installation method that are miniaturized, lightweight, have good focusing effect, simple debugging method, and low energy consumption.

Concrete technical scheme of the present invention is:

A laser micro-thruster optical system, including a semiconductor laser arranged inside the laser micro-thruster, a diffraction element high-order aspheric micro-lens array, and a target belt;

The high-order aspheric microlens array of the diffraction element is installed between the outgoing light of the semiconductor laser and the incident light of the target belt; the outgoing light of the semiconductor laser is converged by the high-order aspheric microlens array of the diffraction element to form a laser target surface; the laser The target surface coincides with the target belt;

The target band is ablated under the action of laser light; the target band is made of black ink paper or double base medicine.

The installation method of this optical system is now provided based on the above-mentioned laser micro thruster optical system, it is characterized in that, comprises the following steps:

Step 1] The diffractive element high-order aspheric microlens array is composed of a plurality of diffractive element aspheric microlenses connected. The steps for connecting the diffractive element high-order aspheric microlens array are:

Step 1.1) Place the first diffraction element high-order aspheric microlens on the two-dimensional adjustment table of the combined measuring instrument, find the position where the first diffraction element high-order aspheric microlens is placed through the microscope system of the combined measuring instrument, and record this position as the initial position;

Step 1.2) By moving the two-dimensional adjustment stage, the first diffraction element high-order aspheric microlens is transferred out of the center of the field of view of the microscope system, and then the second diffraction element high-order aspheric microlens is placed in the two-dimensional adjustment on the stage, and connect the first diffraction element high-order aspheric microlens with the second diffraction element high-order aspheric microlens;

Step 1.3) Observe the posture of the second diffraction element high-order aspheric microlens through the imaging of the monitor set on the combined measuring instrument, and adjust the posture of the second diffraction element high-order aspheric microlens to ensure the first The first diffraction element high-order aspheric microlens and the second diffraction element high-order aspheric microlens confocal surface;

Step 1.4) Repeat steps 1.2) and 1.3), connect the required multiple diffraction element high-order aspheric microlenses, and observe the attitude of each diffraction element high-order aspheric microlens through the monitor during the connection process. Adjusting the posture of each diffraction element high-order aspheric microlens, so that multiple diffraction element high-order aspheric microlenses have confocal surfaces, and finally form a diffraction element high-order aspheric microlens array;

Step 2] Place the laser thruster on the two-dimensional adjustment table, then install the semiconductor laser and the target tape into the laser micro thruster, and then set the high-order aspheric microlens array of the diffraction element installed in step 1.4) on the Between the semiconductor laser and the target tape, use the microscope system of the combined measuring instrument to adjust until the laser target surface formed after the light emitted by the semiconductor laser is converged by the high-order aspheric micro-lens array of the diffraction element coincides with the target tape, and the target tape is ablated , resulting in a strong impetus.

The above-mentioned diffraction element high-order aspheric microlens array is connected by a plurality of diffraction element high-order aspheric microlenses through adhesive bonding.

A semiconductor laser target bar heat sink for heat dissipation of the semiconductor laser is installed on the semiconductor laser.

The beneficial effects of the present invention are:

1. The optical system of the laser micro-thruster and its installation method, the optical system adopts the high-order aspheric micro-lens array of the diffraction element for the first time, which changes the previous design method of the laser micro-thruster optical system, and the system structure is simpler and the external dimension is smaller Small;

2. The laser micro-thruster optical system and its installation method, the improved design of the optical system makes its energy efficiency higher, which can greatly reduce the power consumption of the satellite and prolong the service life of the satellite;

3. The laser micro-thruster optical system and its installation method have changed the existing concept of optical system installation and adjustment, using combined measuring instrument monitoring technology to control the attitude and position of each lens in real time, and can quickly adjust the mutual position of each lens , to ensure that the lens array has good consistency;

4. The optical system of the laser micro thruster and its installation method, when installing the optical system, multiple sets of lens arrays can be spliced at the same time by using the two-dimensional adjustment table, which ensures the rapid assembly and adjustment of multiple sets of lens arrays and improves the performance of the multi-set optical system. adjustment efficiency.

Description of drawings

Figure 1 Schematic diagram of the optical system of the laser microthruster.

Fig. 2 Installation diagram of the optical system of the laser micro thruster.

The reference signs are as follows:

1-semiconductor laser target bar heat sink; 2-semiconductor laser; 3-diffraction element high-order aspheric microlens array; 4-target belt; 5-combined measuring instrument; 6-microscope system; 7-two-dimensional adjustment table; 8 - Monitor.

Detailed ways

The laser micro thruster optical system of the present invention and its installation method are described in detail below:

As shown in Figure 1, the laser micro-thruster optical system among the present invention mainly comprises the semiconductor laser 2 that is arranged on the inside of the laser micro-thruster, the diffraction element high-order aspheric micro-lens array 3 and the target belt 4;

The diffraction element high-order aspheric micro-lens array 3 is installed between the outgoing light of the semiconductor laser 2 and the incident light of the target belt; the outgoing light of the semiconductor laser 2 is converged by the high-order aspheric micro-lens array 3 of the diffraction element to form a laser target surface; the laser target surface When it coincides with the target band 4, the target band 4 is ablated at this time, thereby generating powerful energy, which is used to provide the powerful driving force required by the laser micro thruster.

In addition, a semiconductor laser target bar heat sink for heat dissipation of the semiconductor laser is installed on the semiconductor laser.

In particular, the target tape 4 in the present invention is usually made of black ink paper or double base drug.

In conjunction with Fig. 2, the installation method of laser micro-thruster optical system among the present invention, comprises the following steps:

The first is the installation method of the high-order aspheric microlens array of the diffraction element:

Step 1] The diffraction element high-order aspheric microlens array 3 is composed of a plurality of diffraction element aspheric microlenses connected, and the connection steps of the diffraction element high-order aspheric microlens array are:

Step 1.1) Place the first high-order aspheric microlens of the diffraction element on the two-dimensional adjustment stage 7 of the combined measuring instrument 5, and find the first high-order aspheric microlens of the diffraction element through the microscope system 6 of the combined measuring instrument 8 the location where it was placed, and record that location as the initial location;

Step 1.2) By moving the two-dimensional adjustment table 7, the first diffraction element high-order aspheric microlens is transferred out of the center of the field of view of the microscope system 6, and then the second diffraction element high-order aspheric microlens is placed on the second Dimensional adjustment table 7 and connect the first diffraction element high-order aspheric microlens with the second diffraction element high-order aspheric microlens;

Step 1.3) Observe the posture of the second diffraction element high-order aspheric microlens through the monitor 8 arranged on the combined measuring instrument 5, adjust the posture of the second diffraction element high-order aspheric microlens to ensure that the first The confocal surface of the diffraction element high-order aspheric microlens and the second diffraction element high-order aspheric microlens;

Step 1.4) Repeat steps 2.2) and 2.3) to connect the required multiple diffraction element high-order aspheric micro-lenses. During the connection process, it is necessary to observe the attitude of each diffraction element high-order aspheric micro-lens through a monitor Thereby adjusting the posture of each diffraction element high-order aspheric microlens, so that multiple diffraction element high-order aspheric microlenses have confocal surfaces, and finally form a diffraction element high-order aspheric microlens array 3;

Step 2] Place the laser thruster on the two-dimensional adjustment table 7, then install the semiconductor laser 2 and the target belt 4 into the laser microthruster, and then install the high-order aspheric microlens of the diffraction element installed in step 1.4) The array 3 is set between the semiconductor laser 2 and the target belt 4, and is adjusted by the microscope system 6 of the combined measuring instrument 5 until the laser target surface formed after the light emitted by the semiconductor laser 2 is converged by the high-order aspheric microlens array 3 of the diffraction element When it coincides with the target band 4, the target band 4 is ablated, thereby generating a strong driving force.

In particular, the high-order aspheric microlens array of the diffraction element in the present invention is formed by connecting a plurality of high-order aspheric microlenses of the diffraction element through adhesive bonding.

By using the high-order aspheric lens of the diffraction element, the number of optical elements used can be effectively reduced, so that the overall size of the optical system can be reduced, and the utilization rate of light energy can be effectively improved. The final light energy utilization rate is improved by the previous 65% can be increased to 86%.

Claims (5)

1. A laser micro-thruster optical system, characterized in that: comprise a semiconductor laser arranged inside the laser micro-thruster, a diffraction element high-order aspheric microlens array and a target band; The high-order aspheric microlens array of the diffraction element is installed between the outgoing light of the semiconductor laser and the incident light of the target belt; the outgoing light of the semiconductor laser is converged by the high-order aspheric microlens array of the diffraction element to form a laser target surface; the laser The target surface coincides with the target belt; The target band is ablated under the action of laser light; the target band is made of black ink paper or double base medicine. 2. A method for installing a laser micro-thruster optical system, comprising the following steps: 1] Since the diffraction element high-order aspheric microlens array is composed of multiple diffraction element aspheric microlenses, the connection steps of the diffraction element high-order aspheric microlens array are: 1.1) Place the first diffraction element high-order aspheric microlens on the two-dimensional adjustment table of the combined measuring instrument, find the position where the first diffraction element high-order aspheric microlens is placed through the microscope system of the combined measuring instrument, and record this position as the initial position; 1.2) Through the movement of the two-dimensional adjustment stage, the first diffraction element high-order aspheric microlens is transferred out of the center of the field of view of the microscope system, and then the second diffraction element high-order aspheric microlens is placed on the two-dimensional adjustment stage and connect the first diffraction element high-order aspheric microlens with the second diffraction element high-order aspheric microlens; 1.3) Observe the posture of the high-order aspheric microlens of the second diffraction element through the imaging of the monitor set on the combined measuring instrument, and adjust the posture of the high-order aspheric microlens of the second diffraction element to ensure that the first The confocal surface of the diffraction element high-order aspheric microlens and the second diffraction element high-order aspheric microlens; 1.4) Repeat steps 1.2) and 1.3) to connect the required high-order aspheric micro-lenses of the diffraction elements. During the connection process, it is necessary to observe the posture of each high-order aspheric micro-lens of the diffraction elements through the monitor to adjust The posture of each diffraction element high-order aspheric microlens makes the multiple diffraction element high-order aspheric microlenses confocal, and finally forms a diffraction element high-order aspheric microlens array; 2] Place the laser thruster on the two-dimensional adjustment table, then install the semiconductor laser and the target tape into the laser microthruster, and then set the high-order aspheric microlens array of the diffraction element installed in step 1.4) on the The gap between the semiconductor laser and the target tape is adjusted by the microscope system of the combined measuring instrument until the laser target surface formed after the light emitted by the semiconductor laser is converged by the high-order aspheric micro-lens array of the diffraction element coincides with the target tape. 3. The laser micro-thruster optical system according to claim 1, characterized in that: the diffraction element high-order aspheric microlens array is connected by a plurality of diffraction element high-order aspheric microlenses through glue bonding. 4. the installation method of laser micro thruster optical system according to claim 2, is characterized in that: described diffraction element high-order aspheric microlens array is by a plurality of diffraction element high-order aspheric microlenses by bonding way to connect. 5. The laser micro thruster optical system according to claim 1 or 3, characterized in that: a semiconductor laser target bar heat sink for heat dissipation of the semiconductor laser is installed on the semiconductor laser.