JP6182949B2 - Wavefront compensation device for light beam, wavefront compensation method, and program thereof - Google Patents

Description

  The present invention relates to a wavefront compensator for a light beam, a wavefront compensation method, and a program thereof that compensate for wavefront disturbance by modulating the wavefront of the light beam.

  In recent years, satellites and observation equipment that can be mounted on aircraft have become more sophisticated, and the amount of acquired information has increased. For this reason, optical space communication using a light beam capable of achieving higher-speed communication from radio waves as conventional information transmission means has been proposed. In 2006, the optical inter-satellite communication experiment satellite "Kirari" succeeded in the world for the first time in the world.

  Unlike the outer space, in the information transmission from the satellite to the ground and the information transmission from the aircraft to the ground, it propagates in the atmosphere. Light that has passed through space, particularly light that has passed through a low-uniformity space such as the atmosphere, has a phenomenon in which the wavefront is disturbed because the spatial phase distribution changes during spatial propagation.

  In optical devices that require high accuracy, wavefront disturbance becomes a major problem. For example, in an apparatus using an optical fiber, the coupling efficiency to the optical fiber varies depending on only the wavefront, and a communication error occurs.

  On the other hand, a technique related to wavefront compensation using a spatial phase modulator and a wavefront sensor is known as a technique for suppressing wavefront changes caused by the atmosphere (Patent Document 1). Here, the wavefront compensation is a technique for compensating the wavefront by controlling the spatial phase modulator so as to cancel the phase distribution acquired by the wavefront sensor that acquires the spatial phase distribution.

  In this wavefront compensation device, for example, an error between the target wavefront and the wavefront acquired by the wavefront sensor is fed back to compensate for the disturbed wavefront. Here, the target wavefront means, for example, a wavefront having the highest coupling efficiency to the optical fiber.

  In order to increase the coupling efficiency to the optical fiber, high accuracy is required for the optical member and also for its assembly and adjustment. This adjustment usually requires a skilled technician to spend time, and is expensive.

  In particular, in an optical apparatus equipped with a spatial phase modulator, adjustment of the spatial phase modulator is difficult because it has many variables. In addition, even if the target wavefront is set at the time of manufacturing, there may be a difference between the set target wavefront and the desired target wavefront due to mechanical distortion caused by vibration and shock during movement and installation. is there.

To solve this problem, there is a method of automatically adjusting the optical system to an optimum state at the start of use.
Since this wavefront adjustment has many parameters to be adjusted and there are many local solutions, a probabilistic search method, for example, a search method using a genetic algorithm is known as a corresponding method (Patent Document 2).
This genetic algorithm is characterized in that parameters are adjusted by simulating the process of evolution of organisms such as drought, crossover, and mutation.

  Similarly, a light control apparatus that performs control related to wavefront adjustment of the above-described light using a genetic algorithm has been known (Patent Documents 3, 4, and 5).

JP-A-10-239600 Japanese Patent No. 3957223 (Japanese Patent Laid-Open No. 2003-204100) JP 2002-122758 A JP 2009-86248 A Japanese Patent Laid-Open No. 2003-162706

  In each of the related technologies described above, the probabilistic search method using a genetic algorithm is less likely to fall into a local solution than the hill-climbing search method that adjusts each parameter in a better direction while finely moving each parameter. Compared with the brute force method in which all combinations of parameters to be adjusted are tried, there is a feature that the search time is not required.

  However, the search time in the probabilistic search method is not sufficiently fast when there are many parameters to be adjusted, as in the optical system including the spatial phase modulator described above, for example. Yes.

  As a technique for solving this problem, Japanese Patent Application Laid-Open No. 2003-26083 discloses a technique for performing a search using a stochastic search method that is unlikely to fall into local release at the initial stage of the search and performing a search using a hill-climbing method with high search efficiency after the search progresses and converges. Although proposed, the search time cannot be sufficiently shortened.

(Object of invention)
The present invention improves the inconveniences of the related art, obtains the optimized parameters for the wavefront adjustment of the input beam light in a short time, and enables the wavefront adjustment to be processed quickly. It is an object of the present invention to provide an apparatus, a wavefront compensation method, and a program thereof.

In order to achieve the above object, a wavefront compensation device for a light beam according to the present invention is a wavefront compensation device for a light beam comprising a spatial phase modulation unit that compensates for disturbance of the wavefront of a light beam incident on a projection target. ,
The spatial phase modulation unit is provided with a plurality of search units having different search spaces for setting and controlling the modulation operation of the spatial phase modulation unit to an optimum state, and each search unit is connected via the projection target unit. A parameter generator for searching for a plurality of parameters for compensating and optimizing the wavefront disturbance of the light beam;
A configuration is adopted in which a search unit switching control unit that switches and connects each search unit from one to the other is provided for the spatial phase modulation unit.

In order to achieve the above object, a light beam wavefront compensation method according to the present invention includes a light beam including a spatial phase modulation unit that compensates for a disturbance of a wavefront of a light beam incident on a projection unit using a phase modulation method. In the wavefront compensation device,
A plurality of search units having different search spaces input information on the light wavefront of the light beam and its light intensity via the projection unit (wavefront information input processing step), and the wavefront of the input light beam The parameter generation unit of each search unit searches for a plurality of parameters for compensating and optimizing the disturbance over time (parameter search processing step), and refers to the searched plurality of parameters The spatial phase modulation unit modulates the wavefront of the light beam to compensate for the disturbance of the wavefront of the light beam (wavefront compensation processing step). The switching control unit operates according to a predetermined switching condition, and adopts a configuration in which the one search unit being connected to the spatial phase modulation unit is switched and connected to the other search unit.

Furthermore, in order to achieve the above object, a light beam wavefront compensation program according to the present invention includes:
In a wavefront compensator for a light beam having a spatial phase modulation unit that compensates for a disturbance of a wavefront of a light beam incident on a projection unit using a phase modulation method,
First and second input processing functions for performing input processing on the light wavefront of the light beam and information on the light intensity separately at least in two places via the projection part,
A plurality of parameters for compensating and optimizing the wavefront disturbance of each input light beam are searched and distributed over time corresponding to the first input processing function and the second input processing function. The first and second parameter sharing search processing functions for storing
And providing a control signal setting processing function for sending a plurality of parameters divided and searched to the spatial phase modulation unit as a wavefront compensation control signal,
A switching condition that functions when time-dependent switching is performed when the first and second parameter sharing search processing functions are executed, and a search processing result obtained by executing the first parameter sharing search processing function is preset. Is provided with a shared search switching control function for switching and controlling the search processing operation of the first parameter shared search processing function to the search processing operation by the second parameter shared search processing function,
A configuration is adopted in which each of these processing functions and control functions are realized by a computer.

  Since the present invention is configured as described above, according to this, a plurality of search units having a search space having a small search space and a search unit having a large search space are used as search units for driving and controlling the spatial phase modulator for adjusting the light wavefront. In addition to providing a search unit and switching connection from one to the other during the search, the optimized parameters for the wavefront adjustment can be obtained effectively in a short time, thereby making wavefront compensation smoother. In addition, it is possible to provide an excellent wavefront compensation device for light beam, a wavefront compensation method, and a program thereof that can simultaneously achieve high search efficiency and high search accuracy when searching for parameters.

1 is a block diagram showing a basic configuration of a light beam wavefront compensation apparatus according to a first embodiment of the present invention. It is a flowchart which shows the process of the genetic algorithm in each search part disclosed in FIG. It is a graph which shows the magnitude | size of the influence which the coefficient of each term of the Zernike polynomial used as a mode which expresses phase modulation information in 1st Embodiment disclosed in FIG. 1 has on a wavefront aberration. It is the table | surface which compared the characteristic of the mode group generally known. It is a block diagram which shows the specific structure of 1st Embodiment disclosed in FIG. It is a flowchart which shows operation | movement of the whole apparatus in 1st Embodiment disclosed in FIG. It is a block diagram which shows 2nd Embodiment of this invention. It is a block diagram shown in 3rd Embodiment of this invention. It is a flowchart which shows operation | movement of the search part in 3rd Embodiment disclosed in FIG.

  Embodiments of a wavefront compensation device for a light beam according to the present invention will be described below with reference to the accompanying drawings.

[First Embodiment]
First, a basic configuration including the basic contents of the light beam wavefront compensation apparatus according to the first embodiment will be described, and then the specific configuration contents will be described.

  First, in FIGS. 1 and 2, the light beam wavefront compensation device includes a spatial phase modulation unit 11 that adjusts and compensates for a wavefront disturbance of a light beam sent toward the projection unit 12 using a phase modulation method. Yes. That is, the incident light beam is irradiated to the projection target part 12 after being subjected to wavefront modulation from the spatial phase modulation part 11.

The spatial phase modulation unit 11 is provided with a first search unit 13 and a second search unit 23 that set and control the modulation operation of the spatial phase modulation unit 11 to an optimum state.
In addition, the first and second search units 13 and 23 include search switching control units that switch the connection of the search units 13 and 23 from one to the other as necessary with respect to the spatial phase modulation unit 11. 41 is attached.

  Each of the search units 13 and 23 obtains the spatial phase distribution of the wavefront related to the disturbance of the wavefront of the light beam via the projection unit 12 and compensates for the disturbance of the wavefront. Parameter generation units 14 and 24 for searching and generating a plurality of optimized parameters, and operation control units 13A and 23A for controlling the operation of the parameter generation units 14 and 24. In the first embodiment, the search units 13 and 23 are configured to search for parameters in different search modes and improve the efficiency.

  Among these, the parameter generation unit 14 of the search unit 13 generates the plurality of parameters by applying a genetic algorithm which is a stochastic search method corresponding to the wavefront of the light beam, which will be described in detail later. And it has a function to specify.

  The above-described search switching control unit 41 operates when the switching determination information from one of the operating search units 13 is sent, and determines whether or not the switching switching control unit 41 conforms to a preset switching condition. A determination function 41A and a switching control signal transmission function 41B that transmits a switching control signal to the one search unit when it is determined that the switching condition is satisfied.

  Further, one search unit 13 operates by referring to the switching control signal from the search switching control unit 41, and parameter information (gene information) that has been searched for the other search unit 23 so far. And a search operation command function 13A for commanding a new search.

  Reference numeral 42 denotes an information conversion unit. The information conversion unit 42 is interposed between the one search unit 13 and the other search unit 23 described above. The information conversion unit 42 converts the parameter information (gene information) from the one search unit 13 into parameter information (gene information) in a form suitable for the other search unit 23, and A data conversion function 42A for sending to the unit 23 is provided.

  That is, the data conversion function 42A of the information conversion unit 42 converts part of the parameter information received from the one search unit 13 into parameter information suitable for the other search unit 23, and converts the parameter information to the other search unit 23. It is comprised so that it may transmit to 23.

  Here, the spatial phase modulator 11 is a device that can spatially control the phases of light in a plurality of regions with reference to an external signal. Examples of such a device include a deformable mirror and a liquid crystal panel.

Further, the projected part 12 varies depending on the target system.
In the case of an optical space communication system, the projection unit 12 collects a light beam by a convex lens or a concave mirror and enters the optical fiber or photoelectric conversion element.

  On the other hand, in a system that is incident on an optical fiber, a wavefront change is a coupling efficiency change, so that the effect of wavefront compensation is great. Furthermore, in the case of a laser processing machine, a light beam is condensed by a convex lens or a concave mirror to create a spot on the workpiece. The size of the spot on the workpiece is the minimum processing dimension, and the energy density can be increased as the spot is smaller.

Each search unit 13, 23 controls the modulation operation of the spatial phase modulation unit 11 based on the information from the projection unit 12 as described above. The search units 13 and 23 compensate for the wavefront fluctuation of the light beam and the optical aberration of the optical device, and the spatial phase modulation unit 11 searches for parameters that achieve the desired performance.
Here, the term “search” refers to an action that seeks to obtain a solution by actually making a thought and error when an effective solution cannot be used (or not used) for problem solving.

  The first search unit 13 described above first controls the phase modulation operation of the spatial phase modulation unit 11 based on information from the projection target unit 12. Then, the wavefront fluctuation of the light beam LB incident from the outside and the optical aberration of the wavefront of the light beam LB in the spatial phase modulator 11 are compensated, and a parameter for achieving a desired performance is searched.

Further, the search switching control unit 41 described above determines whether to switch search parameters based on the switching determination information from the first search unit 13.
When switching, a switching control signal is transmitted to the first search unit 13. The first search unit 13 that has received the switching control signal transmits the held parameter information to the information conversion unit 42 as described above.

The second search unit 23 performs a search using the parameter information transmitted via the information conversion unit 42 as an initial value.
Then, the second search unit 23 controls the spatial phase modulation unit 11 based on the information from the projection target unit 12 as in the case of the first search unit 13 described above. Then, the wavefront fluctuation of the light beam incident on the spatial phase modulation unit 11 and the optical aberration of the wavefront are compensated, and a parameter for achieving a desired performance is searched.

(About parameters of each search unit)
Here, each parameter of the first and second search units 13 and 23 will be described.
In the first embodiment, the first search unit 13 to search first uses the coefficient value of the mode with a small search space as a parameter, and the second search unit 23 to search later uses an input signal of an element with a wide search space. A search method using parameters is adopted.

Although specifically described later, the method of searching for the coefficient value of the mode using the Zernike polynomial or the Fourier series can search in a short time with a small search space, that is, the search efficiency is good.
However, the shape of the device of the spatial phase modulation unit 11 cannot be expressed finely to a shape that can be originally expressed.

Therefore, at the initial stage of the search, a mode coefficient value with good search efficiency is searched. When the search progresses to some extent, the mode coefficient value is converted into a signal value of each element, and the signal value of each element is searched as a parameter.
According to this method, high search efficiency and high search accuracy are achieved at the same time.
The search space can be calculated by (number of modes) × (number of modes taken). When the signal value of each element is used as a parameter, the number of elements corresponds to the number of modes.

  In the present invention, since the search space has a meaning, the Zernike polynomial and the mode number from the Zernike polynomial with a small number of modes can be used in addition to the conversion from the coefficient value of the mode using the Fourier series to the signal value of each element. It may be converted into a Fourier series having a large amount of. Alternatively, a Zernike polynomial having a small number of modes may be converted into a Zernike polynomial having a large number of modes.

  Further, by reducing the number of cases that each mode can take, the actual search space may be reduced.

  In the following, for simplicity, unless otherwise specified, the system to be applied is an optical communication system, and the projected part 12 is composed of a convex lens, an optical fiber, a photoelectric conversion element, etc., and light is incident on the optical fiber by the convex lens. The description will be made on the assumption that the light guided through the optical fiber is converted into an electrical signal by the photoelectric conversion element.

  However, this does not limit the applicable configuration content to the configuration of the communication system and the projection target. The wavefront compensation device is not limited to this example, and can be used in common with other optical system devices that want to reduce the influence of wavefront aberration.

(About parameter optimization)
Here, a basic method of a genetic algorithm, which is one of the probabilistic search methods, will be described as the probabilistic search method performed by the first search unit 13.
The genetic algorithm is a kind of probabilistic search method that imitates the process of optimizing the environment while being deceived.

FIG. 2 is a flowchart showing an example of a procedure for optimizing the parameters generated by the search by this genetic algorithm.
The search by this genetic algorithm is executed with reference to a command from the operation control unit 13A provided in the search unit 13 described above.

  In FIG. 2, first, a large number of individuals having random genes are generated (FIG. 2: step S101). A gene is a group of adjustment parameters of a system to be optimized. For example, if there are 10 adjustment parameters, 10 numerical values are genes.

Next, each individual is evaluated (FIG. 2: step S102).
Here, the evaluation corresponds to how much the organism is suitable for the environment. Establish an evaluation index that shows higher values for superior individuals with genes. The evaluation index may be a simulation result or a physical quantity detected by inputting a parameter to a system to be actually adjusted. In the example of optical space communication, for example, the optical power is incident on an optical fiber.

  Then, the cycle of evaluation and survival selection, crossover selection, crossover, and mutation, which will be described later, is set as one generation, and by repeating the generational change, excellent individuals appear gradually (that is, the parameters are optimized). become. For this reason, following the above evaluation, it is checked whether or not the required number of generations has been changed in advance (FIG. 2: step S103).

  If the required number of generations has not been reached, the answer is “No” and, for example, two excellent individuals are selected from the evaluated individual group and crossed (FIG. 2: steps S104 and S105). Selection and crossover are equivalent to being able to leave more children as excellent individuals. The selection in this case is performed with reference to the evaluation value.

  In the genetic algorithm, there is generally a roulette selection in which an individual with a higher evaluation value has a higher selection probability and performs an uneven random selection. There are many other tournament selections, elite selections, and combinations thereof.

  Crossover is to create a new individual by multiplying the genes of two selected individuals. As a crossover type, a random position on a gene is selected, divided into two parts before and after that, and a one-point crossover method in which the divided parameters are exchanged, or a two-point crossover method in which the selected position becomes two points. is there.

  Further, among the individuals born by crossover, some of the children are mutated (FIG. 2: step S106). Mutation is a phenomenon that occurs in living organisms. Rewriting some of the parameters to get the required number of children with parameters that are different from both of the parents. As a result, there is a possibility that a child having characteristics not found in the parent generation may be born (FIG. 2: step S107). If not, the process returns to step S105. If it is born, the process returns to step S102, and the generational change of the genetic algorithm is repeated from the individual evaluation.

  There is a method in which mutation is not performed in the genetic algorithm. There is also a method of allowing some individuals to survive to the next generation from the evaluated population. The selection is made by referring to the evaluation value as in the cross selection. In addition, there is a method in which survival selection is not performed. Then, selection, crossover, and mutation are repeated to generate the necessary number of individuals for the next generation.

  As described above, the cycle of evaluation, survival selection, crossover selection, crossover, and mutation is set as one generation, and by repeating the generational change, excellent individuals appear gradually (parameters are optimized) as described above. Become.

  Then, when the generation change is performed a sufficient number of times to converge the parameters, or when a parameter having a result sufficient to be applied to the system is found, the above-described search ends (FIG. 2: step S108).

  In the flowchart shown in FIG. 2, there is a method that does not perform survival selection and mutation. In addition to the differences in the survival selection, mutation, selection method, and crossover method described above, various methods different from the contents disclosed in this flowchart have been proposed for the genetic algorithm. The applicable genetic algorithm in the invention is not limited to the basic method described above. Further, the search method itself is not limited to the genetic algorithm, and other stochastic search methods such as an annealing method may be applied.

  In the above genetic algorithm, the parameter to be normally adjusted is itself genetic information. In the case of the first embodiment, the signal value given to each element of the spatial phase modulator 11 is gene information. In this case, for example, when the spatial phase modulator 11 is composed of 20 × 20 elements, the gene is composed of 400 parameters.

In this case, there is a method of expressing with a coefficient value of a mode and a mode as a superposition of a plurality of specific shapes (modes) as compared with a method described by a signal value given to each element.
Although the mode shape can be arbitrarily set, phase modulation information can be expressed with a small number of modes by defining each mode as a shape that is physically easily generated. This makes it possible to search with fewer parameters than when the signal value of each element is directly used as genetic information. As such a mode, a Zernike polynomial is often used in an optical system.

ここで、k はゼルニケ多項式の次数、ρは規格化した半径、αはゼルニケ多項式各式の係数である。ゼルニケ多項式は、低次項にチルト，フォーカス，コマ収差など、ザイデルの収差と対応した収差成分分解されたモードであり、光学的に発生しやすい波面収差を表現することに適している。 (Zernike polynomial)
The Zernike polynomial is expressed by the following equation.

Here, k is the degree of the Zernike polynomial, ρ is the normalized radius, and α is a coefficient of each expression of the Zernike polynomial. The Zernike polynomial is a mode in which aberration components are resolved corresponding to Seidel's aberration, such as tilt, focus, and coma aberration in a low-order term, and is suitable for expressing wavefront aberrations that are easily generated optically.

  As a feature of the Zernike polynomial, there is a tendency that the coefficient value is physically smaller as the higher order mode is smaller and the influence on the wavefront aberration is smaller. As an example, in the optical space communication, the magnitude of the influence of the coefficient of each term of the Zernike polynomial on the aberration is shown in the chart of FIG.

The residual aberration was defined as the magnitude of the remaining aberration when all the terms lower than the value indicated by the order were completely compensated. By applying [(D / r ₀ ) ^(5/3) ] consisting of an antenna diameter D for collecting the light beam and a Fried parameter representing the magnitude of atmospheric fluctuation, the light is converted into a physical quantity [rad ^ 2]. As shown in FIG. 3, the influence on the wavefront aberration is greater as the lower order term.

ただし、Ｘ，Ｙは「-1〜1 」で規格化した座標、記号ｋ、ｎは自然数である。
フーリエ級数系はゼルニケ多項式と比較して、工学・数学分野で良く知られている。計算の取り扱いが良い特徴がある。また、ゼルニケ多項式が極座標系であるのにたいして、フーリエ級数系がデカルト座標系である。空間位相変調部１１、又は被投射部１２の形状次第では、計算が簡易になる。 As a mode group different from the Zernike polynomial, there is a mode based on a Fourier series. This is expressed by the following equation.

However, X and Y are coordinates normalized by “−1 to 1”, and symbols k and n are natural numbers.
The Fourier series is well known in the engineering and mathematics field compared to the Zernike polynomials. There is a feature that handling of calculation is good. In addition, while the Zernike polynomial is a polar coordinate system, the Fourier series system is a Cartesian coordinate system. Depending on the shape of the spatial phase modulation section 11 or the projection target section 12, the calculation is simplified.

On the other hand, if each of the elements of the spatial phase modulation unit 11 that is moved is defined as a mode, the signal value given to each element can be expressed as genetic information, which is also expressed by the mode and mode coefficient values. Become.
When the signal value of each element is set to the mode, all the shapes that can be expressed by the spatial phase modulation element can be expressed. Compared to Zernike polynomials and Fourier series, the search space is wide and the search takes time.

FIG. 4 is a chart summarizing the characteristics of the mode groups described above in comparison.
A method of giving a specific shape as a mode, such as a Zernike polynomial or a Fourier series, expresses a shape by a combination of shapes. Therefore, the search space can be adjusted by changing the number of shapes to be combined.
However, since the number of modes is finite, not all forms that the spatial phase modulator 11 can make as a device can be expressed. On the other hand, when the signal value given to the element is directly used as a gene, all forms that the spatial phase modulator 11 can create as a device can be expressed, but there is a problem that the search space is wide.

  The present invention achieves search efficiency by utilizing the difference in features of the modes by switching the modes constituting the gene information during the search.

(Specific configuration contents)
Next, specific contents related to the basic configuration disclosed in FIGS. 1 and 2 and the genetic algorithm described above will be described with reference to FIGS.

  The first search unit 13 described above includes an evaluation unit 19 that performs the above-described individual evaluation in addition to the basic configuration of FIG. 1 described above. Further, the parameter generation unit 14 described above includes an individual information storage unit 16 as storage means for storing information about the individual. The individual information storage unit 16 further includes a gene information storage unit 16A that stores genetic information and an evaluation value information storage unit 16B that stores evaluation value information specified by the evaluation unit 19.

The evaluation unit 19 extracts data that has not been evaluated from the gene information storage unit 16A, converts the gene information into a spatial phase modulation signal, and transmits the spatial phase modulation signal to the spatial phase modulation unit 11. In response to this, the spatial phase modulation unit 11 modulates the phase of the wavefront of the light beam with reference to the transmitted spatial phase modulation signal as described above, and sends it to the projection unit 12.
The projection unit 12 measures the phase-modulated light beam LB and transmits a physical quantity (for example, light intensity) to the evaluation unit 19.

  The evaluation unit 19 converts a physical quantity applied to the light beam sent from the projection unit 12 into an evaluation value, and stores it in the evaluation value information storage unit 16B as an evaluation value corresponding to the extracted gene information. Then, until the evaluation of all the genes stored in the gene information storage unit 16A is completed, the evaluation unit 19 extracts information and performs an operation for conversion into an evaluation value.

When the evaluation by the evaluation unit 19 is completed, the first search unit 13 described above operates the operation control unit 13A described above, and whether or not the search progress of the parameters up to that time satisfies the preset search unit switching condition. To check.
When the search unit switching condition is not satisfied, the first search unit 13 described above shifts to selection, survival, and crossover operations.

  Here, the above-described parameter generation unit 14 of the first search unit 13 further extracts gene information and evaluation value information from the individual information storage unit 16 in order to execute the above selection, survival, and crossover operations. In addition, a selection unit 17 that selects an individual that survives by using this and stores it in the gene information storage unit 16A, and a gene generation unit 18 that generates a new gene are provided.

  Among these, the gene generation unit 18 has a function of creating a required number of individuals of random genes and storing information in the gene information storage unit 16A of the individual information storage unit 16.

  Further, when the selection unit 17 extracts the gene information and the evaluation value information from the individual information storage unit 16, the selection unit 17 deletes the information in the common individual information storage unit 16. Further, using the extracted gene information and evaluation value information, a living individual is selected and the information is stored in the gene information storage unit 16A. Specifically, it has a function of selecting two individuals to be crossed and transmitting them to the gene generator 18.

  Further, the gene generation unit 18 has a function of generating a new gene corresponding to the search parameter by crossing the two genes sent from the selection unit 17. At the same time, the gene generation unit 18 has a function of generating a mutation in a gene generated with a certain probability. The generated gene information is stored in the gene information storage unit 16A. The selection and crossover are continued until the necessary number of gene information is obtained.

  When the required number of genes is available, the first generation is complete. Then, evaluation, selection, survival, and crossover are repeated again.

  On the other hand, when the parameter search process up to that point by the first search unit 13 satisfies the switching condition, the search switching control unit 41 transmits a switching control signal to the first search unit 13. The first search unit 13 that has received the switching control signal transmits the held parameter information to the information conversion unit 42.

  The information conversion unit 42 will be described in detail later, but the parameter information transmitted from the first search unit 13 is converted into parameter information handled by the second search unit 23, and the converted parameter information is A function of transmitting to the second search unit 23 is provided.

  For example, when the first search unit 13 deals with gene information using Zernike polynomials as parameters, the second search unit 23 handles gene information using signal values of the respective elements as parameters. To be done.

  Here, the second search unit 23 is also configured in the same manner as the first search unit 13 described above, and the fixed information storage unit 26 includes a gene information storage unit 26A and an evaluation value information storage unit 26B that function in the same manner. And a selection unit 27, a gene generation unit 28, and an evaluation unit 29.

Here, the fixed information storage unit 26, the selection unit 27, and the gene generation unit 28 constitute a parameter generation unit 24 that functions in the same manner as the parameter generation unit 14 described above.
Further, the second search unit 23 includes an operation control unit 23A that controls the operation of the parameter generation unit 24 and a search operation command function 23B that transmits an operation command to another search unit (not shown). (See FIG. 1).

Then, the second search unit 23 uses the parameter information transmitted from the information conversion unit 42 as an initial value, and continues the subsequent search as in the case of the first search unit 13.
That is, the second search unit 23 controls the phase modulation operation of the spatial phase modulation unit 11 based on information from the projection target unit 12. As in the case of the first search unit 13, parameters for compensating for wavefront fluctuations of the light beam incident on the spatial phase modulation unit 11 and optical aberrations of the wavefront and achieving the desired performance of the spatial phase modulation unit 11. Explore.

  The second search unit 23 repeats the search in the same manner as in the first search unit 13, and the generation change is performed a sufficient number of times for the parameters to converge or is sufficient to be applied to the system. The search is terminated when a result parameter is found.

(About switching conditions)
Here, regarding the determination condition (switching condition) when the search switching control unit 41 described above switches the search unit from the search unit A (first search unit 13) to the search unit B (second search unit 23). explain.

  A). The first condition is whether or not the generation alternation number (that is, the number of times of search execution) has reached a preset specified value. The search switching control unit 41 counts the number of generation changes described above, and ends the search when the specified number of times is reached. Since the genetic algorithm searches as the generation progresses, the generation alternation number has a correlation with the search progress, and the progress of parameter optimization can be managed by managing the generation alternation number.

The problem with this method is that it is a probabilistic search, so the generation alternation number and the search progress are correlated but not the same, so that the search parameters do not change at the same timing with respect to the search progress. .
On the other hand, a good point of this method is that the time required for the search can be made the same every time, especially for the search end condition.

B). The second condition is whether or not the highest evaluation value has reached a desired value (that is, whether or not a desired performance has been achieved as an optical device).
The search switching control unit 41 acquires the maximum value of the evaluation value when the evaluation of each generation is completed, and ends the search when the acquired value reaches a desired value.
In optical systems that optimize parameters, the theoretical value of the evaluation value is often known from physical calculations. Even if the theoretical value is not known, it is possible to perform optimization by determining a necessary evaluation value based on the specification.

  When the number of parameters of a gene to be searched changes in the middle as in the first embodiment, this condition can be applied by setting a desired value in the parameter being searched at that time.

  The problem with this method is that since it is a stochastic search, the time until the evaluation value reaches the desired value is unknown. In the worst case, it may fall into a local solution and may not reach a desired value over time. This can be solved by combining the first condition described above and performing an operation such as ending the search or restarting the search from the beginning if the generation is changed a certain number of times without reaching the desired value.

  The good point of this method is that it can be agreed that the search end condition achieves the desired performance as the device.

C). The third condition is whether or not the variation (that is, the variance) of the evaluation value has become small.
The search switching control unit 41 obtains an evaluation value and calculates a variance when the evaluation of each generation is completed. When the variance falls below a predetermined value, the search is terminated. In a search using a genetic algorithm, the individuality of each gene is usually lost as the search is advanced, and approaches a similar value.

From this, it can be said that the variation in the evaluation value indicates the search efficiency. The problem with this method is that the evaluation value does not necessarily reach the desired value when the search progresses. Therefore, the required performance may not be achieved at the end of the search.
The good point of this method is that the search efficiency can be managed because the transition of search efficiency can be managed. Here, the search efficiency indicates the sharpness of the rise for obtaining high search accuracy close to the ideal state.

  Here, among the plurality of switching conditions, one switching condition may be applied, or a plurality of switching conditions may be combined. The combination method may be permitted when all of the plurality of switching conditions are satisfied, or may be permitted when each condition is digitized and the total value of the numerical values is equal to or greater than a certain value. Further, the type of condition used for the parameter change condition and the type of condition used for the search end condition may be different.

(Specific operation of the first embodiment)
Next, the specific operation of the first embodiment will be described with reference to the flowchart of FIG.
First, the basic contents of the operation will be described.
First, the search part 15 inputs the information concerning the light wavefront of the light beam LB and its light intensity via the projection part 12 (wavefront information input processing step).

  Subsequently, a plurality of parameters for acquiring the spatial phase distribution of the wavefront relating to the disturbance of the wavefront of the input light beam LB as wavefront information and compensating and optimizing the disturbance are obtained as the search units 13, 23 parameter generation units 14 and 24 share and search over time (parameter search processing step).

The spatial phase modulation unit phase-modulates the wavefront of the light beam with reference to the searched plurality of parameters so that the disturbance of the wavefront of the light beam LB is smoothly processed and compensated (wavefront compensation processing step) .
Here, in the parameter search processing step described above, the search switching control unit 41 provided in advance operates according to a predetermined switching condition, and the one search unit being connected to the spatial phase modulation unit 11 The connection is switched from 13 to the other search unit 23.

  Further, in the switching control process by the search switching control unit 41 described above, the search switching control unit 41 operates first when switching determination information is sent from one of the operating search units 13. Whether or not the switching condition set in advance is determined (switching condition determination step), and when it is determined that the switching condition is satisfied, the switching control signal is sent to the one search unit 13. (Switching control signal transmission step).

  With reference to the switching control signal from the search switching control unit 41, the one search unit 13 functions and the parameter information that has been searched so far is transmitted to the other search unit 23 to perform a new search. It was set as the structure which command | commands (search operation command process).

  Here, the parameter information transmitted from the one search unit 13 to the other search unit 23 is obtained by the information conversion unit 42 interposed in advance between the search units 13 and 23. The parameter information from the unit 13 is converted into parameter information in a form suitable for the other search unit 23 and sent to the other search unit 23 (data conversion process step).

This will be described more specifically below.
Here, for convenience of explanation, one search unit 13 is referred to as a search unit A, and the other search unit 23 is referred to as a search unit B.
First, the light beam LB sent from the outside is sent to the projection target part 12 via the spatial phase modulation part 11. In this case, as described above, the search unit A performs an operation of creating and outputting a modulation control signal for correcting the disturbance of the wavefront of the light beam LB.

  First, the search unit A creates a required number of random gene individuals in advance by the gene generation unit 18 that forms a part thereof, and stores the information in the gene information storage unit 16A (FIG. 6: step S201).

Next, the evaluation unit 19 of the search unit A extracts data that has not been evaluated from the gene information storage unit 16A, and converts the extracted data (gene information) into a control signal for spatial phase modulation. The data is sent to the phase modulator 11 (FIG. 6: Steps S202 and S203).
Here, the spatial phase modulation unit 11 performs a modulation operation (phase modulation) for compensating for the wavefront disturbance of the light beam LB with reference to the modulation signal sent from the search unit A (FIG. 6: step S204). .

  Subsequently, when measurement data (for example, light intensity data) of the modulated light beam LB is sent from the projection unit 12 to the evaluation unit 19, the evaluation unit 19 evaluates the physical quantity (light intensity data). It converts into a value and preserve | saves it in the evaluation value information storage part 16B (FIG. 6: step S205, S206).

  Here, the search unit A determines whether there is any gene that has not been evaluated. If there is a gene that has not been evaluated, the process returns to step S202 to continue the modulation signal generation operation (FIG. 6: step S207 / No). On the other hand, if there is no gene that has not been evaluated (FIG. 6: step S207 / Yes), the process proceeds to the next step S208.

  In step S208, first, the search switching control unit 41 acquires switching determination information from the search unit A. When the switching determination information from the search unit A is acquired, the search switching control unit 41 immediately functions and determines whether or not the switching condition is satisfied (FIG. 6: Steps S208 and S209).

  And when it determines with satisfy | filling switching conditions (FIG. 6: step S209 / Yes), the search switching control part 41 sends a switching control signal with respect to the search part A (FIG. 6: step S210). The search unit A functions with reference to the switching control signal, transmits parameter information (gene information) that has been searched so far to the search unit B, and instructs the search unit B to perform a new search. To do. In response to this new search command, the relay information converter 42 functions immediately, converts the parameter information of the search unit A to be transmitted into parameter information in a form suitable for the other search unit 23, and transmits the other search unit A 23.

  In this case, specifically, the information conversion unit 42 first extracts the gene information corresponding to the parameter information from the gene information storage unit 16A of the search unit A and converts it into the gene information for the search unit B. Then, the gene information is stored in the gene information storage unit 26A of the search unit B, and then the process proceeds to the phase of the search unit B (FIG. 6: steps S211 to S214).

  On the other hand, if it is determined in step S209 that the switching condition is not satisfied (FIG. 6: step S209 / No), the search mode of the search unit B is continued, and the process proceeds to step S215 in FIG. .

In this step S215, first, the selection unit 17 is operated to take out the gene information and the evaluation value information from the individual information storage unit 16 and erase the data in the individual information storage unit 16 (FIG. 6: step S216). . Subsequently, the selection unit 17 selects a living individual using the extracted gene information and evaluation value information, and stores the selected individual in the gene information storage unit 16A (FIG. 6: Step S217).
At the same time, the selection unit 17 selects two individuals to be crossed using the extracted gene information and evaluation value information, and sends them to the gene generation unit 18 (FIG. 6: step S218).

  Subsequently, the gene generation unit 18 generates a new gene by crossing the transmitted two genes. At the same time, the gene generator 18 generates a mutation in the gene generated with a certain probability (FIG. 6: steps S219 and S220). Thereafter, the gene generation unit 18 stores the gene information related to the generated gene in the gene information storage unit 16A (FIG. 6: step S221).

Next, the search unit A determines whether or not the gene information stored in the gene information storage unit 16A has a preset required number. If there is no necessary amount of gene information, the process proceeds to step S218 to enter an operation for selecting individuals to be crossed over, and the gene generation operation is repeatedly executed (FIG. 6: steps S222 / No, S218).
On the other hand, when there is a necessary number of gene information, the process proceeds to step S202, and a series of flow is executed for data that has not been evaluated (FIG. 6: step S222 / yes, S202).

  That is, as described above, when the required number of genes is obtained, one generation is completed, and evaluation, selection, survival, and crossover are repeated again. Then, generational alternations are performed a sufficient number of times for the parameters to converge, or the resulting parameters sufficient to be applied to the system (ie, optimal parameters for control that can contribute to optimal wavefront compensation) are found. At this point, the search ends.

Here, in the information processing operation of each component, the execution contents in each step (step) may be programmed and realized by a computer equipped in advance with the search units A and B.
In this case, the program may be recorded on a non-temporary recording medium (for example, DVD, CD, flash memory, etc.). In this case, the program is read from the recording medium to the computer and executed.

  In the present embodiment, the computer includes a microcomputer, and further includes an application specific integrated circuit (ASIC) and a field programmable gate array (FPGA).

(About the information converter 42)
Here, the function of the information conversion unit 42 described above will be described.
As an example, it is assumed that both the search unit A that has finished searching and the search unit B that starts searching next are searching using a genetic algorithm.

と表され、探索部Ｂの個体が示す位相変調信号が、モード形状関数Φ_Ｂ とモード係数ａの和として、

と表されるとき、

が成り立つようなモード係数ａを計算することに相当する。 At this time, if it is not necessary to change the number of individuals in each of the search units A and B, the gene parameter of each individual in the search unit A may be converted into the gene parameter of the search unit B.
That is, the genetic parameters of the search unit A and the search unit B are the mode coefficient values of the mode shape functions applied in the search units A and B.
The phase modulation signal indicated by the individual search unit A is the sum of the mode shape function Φ _A and the mode coefficient a.

The phase modulation signal indicated by the individual search unit B is expressed as the sum of the mode shape function Φ _B and the mode coefficient a.

Is expressed as

Is equivalent to calculating the mode coefficient a such that

  In addition, when it is necessary to change the number of individuals in the search unit A and the search unit B from the viewpoint of increasing search efficiency, it is highly likely that an individual with good results will be selected from the individuals output by the search unit A What is necessary is just to make the unbalanced random selection set to random, or to select a required number at random.

(Effect of 1st Embodiment)
Since the first embodiment is configured and operates as described above, according to this, a search unit 13 having a small search space and a search having a large search space as a search unit for driving and controlling the spatial phase modulator 11 for wavefront adjustment. In addition to providing a plurality of search units (two in the first embodiment) consisting of the unit 23 and switching connection from one to the other during the search, the optimized parameters for the wavefront adjustment are It can be effectively obtained in a short time, and not only can wavefront compensation be made more quickly, but also for excellent light beams that can quickly and simultaneously achieve search efficiency and high search accuracy when searching for parameters. A wavefront compensation device can be obtained.

  In addition, when switching the search units A and B, if the search unit 13 having a small search space is initially operated and then switched to the search unit 23 having a large search space from the middle, the search can be performed more efficiently. There are advantages.

  Furthermore, in the first embodiment, when the search units A and B are switched, when the switching determination information is output from the operating first search unit 13 and the switching determination information satisfies a preset switching condition, the search is performed. Since the switching control unit 41 is configured to switch and connect from one search unit A to the other search unit B, the search unit can be switched quickly and smoothly, and between the search units A and B Since the information conversion unit 42 is provided, switching to a search unit with a different search method can be easily performed, which has the advantage that wavefront compensation can be executed more effectively and quickly.

  The present invention relates to the search switching determination unit and the information conversion unit, and does not relate to the selection / crossover / survival method. Regarding the selection / crossover / survival method, any selection method not shown above may be used. For example, the selection may be roulette selection or tournament selection. Survival selection may be omitted. Also, the search method is not limited to the above-described genetic algorithm.

[Modification]
A modification of the search units A and B in the first embodiment will be described.
The search units A and B in this modified example use the coefficient value of the mode in which the search space A has a small search space as a parameter for the light wavefront information sent from the projection unit 12 described above, and search later The search unit B is incorporated so that the input signal of an element having a wide search space is used as a parameter. In addition, a search method capable of switching the search algorithm between the search unit A and the search unit B is set.

  Further, the genetic algorithm described above has a feature that it is difficult to fall into a local maximum. However, after the search progresses and each gene enters approximately the same local region, the speed of optimization is somewhat slow. On the other hand, the parameter search by the hill-climbing method can reach only the local maximum including the point where the search is started, but has a feature that the search speed is fast.

  Therefore, at the same time as changing the parameter group to be searched as in the first embodiment, at the initial stage of the search, the search is performed with a search method that does not easily cause local maximum, and when the search progresses to some extent, the search method is switched to search for the maximum value. Search using an efficient search method.

According to this method, there is an advantage that higher search efficiency and higher search accuracy are achieved than in the first embodiment.
In this case, as a search method suitable for the initial search, a genetic algorithm or a stochastic search method such as an annealing method is desirable.

Next, the function of the information conversion part 42 which implement | achieves 1st Embodiment mentioned above is shown.
As an example, it is assumed that the search unit A that has completed the search performs a search by a genetic algorithm, and the search unit B that starts the next search performs a search by a hill-climbing method.
At this time, if the search unit B searches for all the individuals output by the search unit A, the gene parameters of each individual of the search unit A may be converted into the gene parameters of the search unit B.

  That is, in this case as well, the genetic parameters of the search unit A and the search unit B are the mode coefficient values of the mode shape functions applied in the search units A and B, and are the same as in the first embodiment described above. This is equivalent to calculating the mode coefficient b such that Equations 4 to 6 are satisfied.

  In addition, from the viewpoint of search efficiency and the like, if the search unit B does not search for all the individuals output by the search unit A, there is a high possibility of selecting individuals with good results from the individuals output by the search unit A. What is necessary is just to make the unbalanced random selection made into the state, or to select a required number at random.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG.
In the second embodiment, three search units 13, 23, which generate a spatial phase modulation signal (control parameter) for the spatial phase modulation unit 11 described above by searching for light wavefront information sent from the projection target unit 12. 33 is provided. Note that four or more search units 13, 23, and 33 may be provided.

  That is, in the second embodiment, a search unit 33 is additionally provided in addition to the search units 13 and 23 in the first embodiment (FIG. 1) described above. At the same time, the search unit 23 is provided with a search switching control unit 51 that switches the search unit 23 to the search unit 33 as necessary, and an information conversion unit 52 is further interposed between the search units 23 and 33. Yes.

  Here, a search method different from the search units 13 and 23 described above is incorporated in the additionally equipped search unit 33. The search unit 33 includes a parameter generation unit 34 that functions in the same manner as the search unit 23 described above, and an operation control unit 33A that controls the operation of each component including the parameter generation unit 34. Yes.

  Among these, the search control unit 51 described above has the same function as the search control unit 41 in the first embodiment described above, and the information conversion unit 52 is also equivalent to the information conversion unit 42 in the first embodiment described above. It has the function of.

  That is, in the second embodiment, like the difference between FIG. 7 and FIG. 1, the search unit 33, the search switching control unit 51, and the information conversion unit 52 are added. The number of times can be further increased twice.

And if comprised in this way, according to the parameter and search method to search, it can set so that search efficiency, fitting precision, and the probability of falling into a local solution may differ. Therefore, a more desirable search result can be obtained in a short search time by appropriately changing the search parameter and the search method depending on the search depth.
Other configurations and the operation and effects thereof are the same as those of the first embodiment described above.

[Third Embodiment]
Next, a third embodiment of the light beam wavefront compensation apparatus according to the present invention will be described with reference to FIGS.

The third embodiment is configured by adding a new configuration to the light beam wavefront compensator in the first embodiment described above.
First, the above-described spatial phase modulation unit 11 has a function of modulating and outputting the wavefront disturbance of the light beam with parameters optimized by searching in advance by the search unit 13.
The spatial phase modulation unit 11 is provided with a light division unit 61 that divides and outputs the light beam transmitted from the spatial phase modulation unit 11 into one and the other.

  In addition, the projection unit 12 described above inputs the one light beam from the light splitting unit 61, and an optical sensor 62 that inputs the other light beam and measures its wavefront is connected to the light splitting unit 61. Attached. Further, a wavefront compensation feedback calculation unit 63 is provided that inputs the wavefront information measured by the optical sensor 62 and uses the target wavefront as a target wavefront for feedback control of the spatial phase modulation unit 11.

That is, the third embodiment is different from the basic configuration of the light beam wavefront compensator disclosed in FIG. 5 in the first embodiment described above with respect to the light splitting unit 61, the wavefront sensor 62, and the wavefront compensation feedback calculation. The part 63 is added.
Other configurations and operations are the same as those of the first embodiment described above.

  In the third embodiment having such a configuration, the light beam LB incident from the outside is sent to the light splitting unit 61 via the spatial phase modulation unit 11 before the modulation operation, and the projected unit 12 The light beam LB is divided into two light beams, that is, one light beam LB incident on the light beam LB and the other light beam LB incident on the wavefront sensor 62.

Then, the wavefront of the other light beam LB incident on the wavefront sensor 62 is measured by the wavefront sensor 62. The measured wavefront information is transmitted to the wavefront compensation feedback calculation unit 63. The wavefront compensation feedback calculation unit 63 calculates a difference from a target wavefront assumed in advance, and sends a feedback control signal to the spatial phase modulation unit 11 so as to reduce the difference.
On the other hand, the processing related to the one light beam LB incident on the projection target 12 and the search unit 13 connected thereto is processed in the same manner as the contents disclosed in the first embodiment.

  Next, a basic operation of the light beam wavefront compensation apparatus according to the third embodiment will be described with reference to the flowchart of FIG.

  First, as shown in FIG. 9, in the third embodiment, a parameter search equivalent to the parameter search executed in the first embodiment described above is performed before the full operation of the entire apparatus (for example, at the time of manufacturing or installation of the apparatus). (FIG. 9: Step S301). At this time, it is desirable that the light beam LB incident on the apparatus has a small disturbance.

Then, after the parameter search is completed, the spatial phase modulation unit is modulated with the gene parameter indicating the best evaluation value (FIG. 9: Step S302). The wavefront compensation feedback calculation unit 63 previously stores wavefront information equivalent to the compensated wavefront measurement information acquired by the wavefront sensor 62 at that time as a target wavefront (FIG. 9: step S303), and refers to this wavefront information. Compensation operation is started, and feedback calculation and control are performed (FIG. 9: Step S304).
Other configurations and the effects thereof are the same as those of the first embodiment described above.

  Even in this case, it is possible to obtain the light beam wavefront compensator having the same effects as those of the first embodiment described above, and to effectively and effectively prevent the disturbance of the wavefront of the externally incident light beam described above. Can be compensated.

[Appendix]
About the 1st thru | or 3rd embodiment mentioned above, when the summary of the novel technical content is put together, it is as follows.
In addition, about this new technical content put together below, a part of each embodiment mentioned above is put together, and this invention is not limited to this.

[Appendix 1]
A wavefront compensation device for a light beam provided with a spatial phase modulation unit that compensates for disturbance of a wavefront of a light beam incident on a projection part,
The spatial phase modulation unit is provided with a plurality of search units having different search spaces for setting and controlling the modulation operation of the spatial phase modulation unit in an optimal state,
Each of the search units includes a parameter generation unit that searches for a plurality of parameters for compensating and optimizing the wavefront disturbance of the light beam via the projection unit,
A wavefront compensation device for a light beam, comprising: a search unit switching control unit that switches and connects each search unit from one to the other with respect to the spatial phase modulation unit.

[Appendix 2]
In the wavefront compensation device for a light beam according to attachment 1,
The search switching control unit is operated when the switching determination information from one of the operating search units is sent, and is operated to determine whether or not the switching condition determination function conforms to a preset switching condition. And having a switching control signal transmission function for sending a switching control signal to the one search unit when it is determined that the switching condition is satisfied,
The one search unit operates with reference to a switching control signal from the search switching control unit, transmits parameter information for which the search has been completed to the other search unit, and requests a new search A wavefront compensation device for a light beam comprising a search operation request function.

[Appendix 3]
In the wavefront compensation device for a light beam according to appendix 2,
An information conversion unit is interposed between the one search unit and the other search unit, and the information conversion unit converts the parameter information from the one search unit into parameter information in a form suitable for the other search unit. And a data conversion function for sending the data to the other search unit.

[Appendix 4]
In the wavefront compensation device for a light beam according to attachment 3,
The data conversion function of the information conversion unit converts a part of the parameter information received from the one search unit into parameter information suitable for the other search unit and transmits the parameter information to the other search unit. A wavefront compensation device for a light beam.

[Appendix 5]
In the wavefront compensation device for a light beam according to appendix 1, 2 or 3,
Each of the search units is configured to search for a parameter group to be optimized in search ranges different from each other in advance.

[Appendix 6]
In the wavefront compensation device for a light beam according to appendix 1, 2 or 3,
Each of the search units is configured to optimize the parameter group using a different method when optimizing the parameter group.

[Appendix 7]
In the wavefront compensation device for a light beam according to appendix 6,
The parameter group formed by searching and optimizing the wavefront information from the projected part by any one of the search parts corresponds to a coefficient value of a Zernike polynomial. Wave front compensator for beam.

[Appendix 8]
In the wavefront compensation device for a light beam according to appendix 6,
Of the search methods in which each search unit searches the wavefront information output from the projection unit and optimizes the parameter group, any one search unit employs a probabilistic search method. Wavefront compensation device for light beam.

[Appendix 9]
In the wavefront compensation device for a light beam according to appendix 1, 2 or 3,
When searching for a parameter group targeted by each search unit, the number of parameter groups to be optimized is larger in the other search unit than in the one search unit. Wavefront compensation device for light beams.

[Appendix 10]
In the wavefront compensation device for a light beam according to any one of appendices 1 to 9,
The switching determination information transmitted from the one search unit to the switching control unit is a statistical information on the number of executions of the probabilistic search performed by the one search unit and the results of the probabilistic search execution. A wavefront compensator for a light beam, characterized in that the information includes the dispersion value evaluated in the above or the performance of the optical system achieved by the searched parameters.

[Appendix 11]
In the wavefront compensation device for a light beam according to any one of appendices 1 to 9,
The spatial phase modulation unit has a function of phase-modulating and outputting the light beam with parameters optimized by searching in advance by the search unit,
On the output side of the spatial phase modulation unit, a light splitting unit for splitting the light beam into one and the other and outputting it is attached,
The projected portion inputs the one light beam from the light splitting portion, and an optical sensor that inputs the other light beam and measures its wavefront is provided.
A wavefront compensation apparatus for a light beam, comprising: a wavefront compensation feedback calculation unit that feedback-controls the spatial phase modulation unit using wavefront information measured by the optical sensor as a target wavefront.

[Appendix 12] (Appendix 1)
In a wavefront compensator for a light beam having a spatial phase modulation unit that compensates for a disturbance of a wavefront of a light beam incident on a projection unit using a phase modulation method,
A plurality of search units having different search spaces input information on the light wavefront of the light beam and the light intensity thereof through the projection unit (wavefront information input processing step),
A plurality of parameters for compensating and optimizing the disturbance of the wavefront of the input light beam are searched by the parameter generation unit of each search unit in a time-sharing manner (parameter search processing step),
The spatial phase modulation unit performs phase modulation on the wavefront of the light beam with reference to the searched plurality of parameters to compensate for disturbance of the wavefront of the light beam (wavefront compensation processing step),
In the parameter search processing step, the search unit switching control unit equipped in advance operates according to a predetermined switching condition, and the one search unit connected to the spatial phase modulation unit is searched for the other. A wavefront compensation method for a light beam, characterized by switching to a part.

[Appendix 13] (Appendix 2)
In the wavefront wavefront compensation method according to appendix 12,
In the switching control process by the search switching control unit,
First, when switching determination information from one of the operating search units is sent, the search switching control unit is operated to determine whether or not the switching conditions set in advance are met (switching Condition determination step), when it is determined that the switching condition is met, a switching control signal is sent to the one search unit (switching control signal transmission step),
A configuration in which the one search unit functions with reference to a switching control signal from the search switching control unit, and parameter information that has been searched so far is transmitted to the other search unit to instruct a new search A wavefront compensation method for a light beam characterized in that (search operation commanding step).

[Appendix 14] (Appendix 3)
In the wavefront compensation method for a light beam according to attachment 13,
The parameter information transmitted from the one search unit to the other search unit is obtained by the information conversion unit interposed in advance between the search units, and the parameter information from the one search unit is transferred to the other search unit. A wavefront compensation method for a light beam, characterized in that the information is converted into parameter information in a form suitable for a search unit and sent to the other search unit. (Data conversion process)

[Appendix 15] (Program invention / Appendix 12)
In a wavefront compensator for a light beam having a spatial phase modulation unit that compensates for a disturbance of a wavefront of a light beam incident on a projection unit using a phase modulation method,
First and second input processing functions for performing input processing on the light wavefront of the light beam and information on the light intensity separately at least in two places via the projection part,
A plurality of parameters for compensating and optimizing the disturbance of the wavefront of each input light beam are searched and generated over time corresponding to the first input processing function and the second input processing function. And a first and second parameter sharing search processing function for storing the same,
And providing a control signal setting processing function for sending a plurality of parameters divided and searched to the spatial phase modulation unit as a wavefront compensation control signal,
A switching condition that functions when time-dependent switching is performed when the first and second parameter sharing search processing functions are executed, and a search processing result obtained by executing the first parameter sharing search processing function is preset. Is provided with a shared search switching control function for switching and controlling the search processing operation of the first parameter shared search processing function to the search processing operation by the second parameter shared search processing function,
A wavefront compensation program for a light beam, characterized in that a computer realizes each of these processing functions and control functions.

[Appendix 16] (Appendix 13)
In the wavefront compensation program for a light beam according to attachment 15,
In the shared search switching control function,
When it is determined that the information obtained by one of the parameter sharing search processing functions in operation meets a switching condition set in advance and whether the information meets the switching condition. The parameter sharing search processing function is activated and the parameter information that has been searched is transferred to the other parameter sharing search processing function, and the other parameter sharing search processing function is instructed to continue the new search. It has a search operation command function to
A wavefront compensation program for a light beam, characterized in that each determination function and operation command function is realized by the computer.

  The present invention can be effectively applied to all fields that require compensation for disturbance of the optical wavefront, including laser light for measurement and processing.

DESCRIPTION OF SYMBOLS 11 Spatial phase modulation part 12 Projection part 13,23,33 Search part 13A, 23A Operation control part 13B, 23B Search operation command function 14, 24, 34 Parameter generation part 16 Individual information preservation | save part 17 Selection part 18 Gene generation part 19 Evaluation section 41, 51 Search switching control section 41A Switching condition determination function 41B Switching control signal transmission function 42, 52 Information conversion section 42A, 52A Data conversion function 61 Light split section 62 Wavefront sensor 63 Wavefront compensation feedback calculation section

Claims (9)

A wavefront compensation device for a light beam provided with a spatial phase modulation unit that compensates for disturbance of a wavefront of a light beam incident on a projection part,
The spatial phase modulation unit is provided with a plurality of search units having different search spaces for setting and controlling the modulation operation of the spatial phase modulation unit in an optimal state,
Each of the search units obtains a spatial phase distribution related to the wavefront disturbance of the light beam via the projection unit, and searches for a plurality of parameters for compensating and optimizing the disturbance. Prepared,
The spatial phase modulation part searching unit for switching control unit for switching connection of the respective search section from one to the other provided for Rutotomoni,
An information conversion unit is interposed between the one search unit and the other search unit, and the information conversion unit converts the parameter information from the one search unit into parameter information in a form suitable for the other search unit. It has a data conversion function that converts and sends it to the other search unit,
At the time of the switching connection of each search unit by the search unit switching control unit, the search unit having the smaller search space is initially operated, and the search unit is switched from the middle to the search unit having a larger search space. A wavefront compensation device for a light beam. The wavefront compensation device for a light beam according to claim 1,
The search unit switching control unit is operated when the switching determination information from one of the operating search units is sent, and determines whether or not the switching unit is in conformity with a preset switching condition. A function and a switching control signal transmission function for sending a switching control signal to the one search unit when it is determined that the switching condition is satisfied,
The one search unit operates by referring to the switching control signal from the search unit switching control unit, transmits parameter information that has been searched for to the other search unit, and performs a new search. A wavefront compensation device for a light beam, comprising a search operation command function for commanding. The wavefront compensation device for a light beam according to claim 1 or 2 ,
The data conversion function of the information conversion unit converts a part of the parameter information received from the one search unit into parameter information suitable for the other search unit and transmits the parameter information to the other search unit. A wavefront compensation device for a light beam. In the wavefront compensation device for a light beam according to claim 1, 2, or 3,
Each of the search units is configured to search for a parameter group to be optimized in search ranges different from each other in advance. In the wavefront compensation device for a light beam according to claim 1, 2, or 3,
Each of the search units is configured to optimize the parameter group using a different method when optimizing the parameter group. The wavefront compensation device for a light beam according to claim 5 ,
The parameter group formed by searching and optimizing the wavefront information from the projected part by any one of the search parts corresponds to a coefficient value of a Zernike polynomial. Wave front compensator for beam. The wavefront compensation device for a light beam according to any one of claims 1 to 6 ,
The spatial phase modulation unit has a function of phase-modulating and outputting the light beam with parameters optimized by searching in advance by the search unit,
On the output side of the spatial phase modulation unit, a light splitting unit for splitting the light beam into one and the other and outputting it is attached,
The projected portion inputs the one light beam from the light splitting portion, and an optical sensor that inputs the other light beam and measures its wavefront is provided.
A wavefront compensation apparatus for a light beam, comprising: a wavefront compensation feedback calculation unit that feedback-controls the spatial phase modulation unit using wavefront information measured by the optical sensor as a target wavefront. In a wavefront compensator for a light beam having a spatial phase modulation unit that compensates for a disturbance of a wavefront of a light beam incident on a projection unit using a phase modulation method,
Each search unit inputs information on the light wavefront of the light beam and its light intensity via the projection unit,
A plurality of parameters for compensating and optimizing the disturbance of the wavefront of the input light beam are searched by the parameter generation unit of each search unit in a time-sharing manner,
The spatial phase modulation unit performs phase modulation on the wavefront of the light beam with reference to a plurality of parameters obtained by the search, and compensates for disturbance of the wavefront of the light beam,
Upon search processing of the parameter, in advance switching controller for instrumented searching unit operates in accordance with a predetermined switching condition, the switching from the one search unit in connection to the spatial phase modulation part to the other search unit Control
The parameter information transmitted from the one search unit to the other search unit is obtained by the information conversion unit interposed in advance between the search units, and the parameter information from the one search unit is transferred to the other search unit. Converted into parameter information in a form suitable for the search unit and sent to the other search unit,
In the above-described switching control of each search unit by the search unit switching control unit, the light beam is characterized in that the search unit having the smaller search space is initially operated and switched to the search unit having a larger search space from the middle. Wavefront compensation method. In a wavefront compensator for a light beam having a spatial phase modulation unit that compensates for a disturbance of a wavefront of a light beam incident on a projection unit using a phase modulation method,
First and second input processing functions for individually inputting information on the light wavefront of the light beam and the light intensity thereof to at least each of the plurality of search units via the projection unit;
A plurality of parameters for compensating and optimizing the disturbance of the wave front of each input light beam are set by the one search unit and the other search unit over time corresponding to the first input processing function and the second input processing function. A first and second parameter sharing search processing function for storing and processing this
And providing a control signal setting processing function for sending a plurality of parameters divided and searched to the spatial phase modulation unit as a wavefront compensation control signal,
It functions when time-dependent switching is performed when the first and second parameter sharing search processing functions are executed, and a search processing result obtained by executing the first parameter sharing search processing function is a preset switching. when satisfying the condition, the search processing operation of the first parameter sharing search processing function, provided the shared search switch control function for controlling switching to the search processing operation by the second parameter sharing search processing function,
The parameter information from the one search unit is converted into parameter information in a form suitable for the other search unit, and the data conversion function for sending the parameter information to the other search unit is provided ,
In the switching control of each search unit by the shared search switching control function, first, the search unit having a smaller search space is operated, and the search unit is switched from the middle to the search unit having a larger search space.
A wavefront compensation program for a light beam, characterized in that a computer realizes each of these processing functions and control functions.

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