Random number generator and generation method based on crystal resonant cavity optical chaos

Abstract

The invention relates to the technical field of photoelectrons, in particular to a random number generator based on crystal resonant cavity optical chaos and a generation method. Comprising a semiconductor laser, a focus lens, a beam splitter and combiner, a reflector, a first coupling prism, a second coupling prism, a crystal resonant cavity, a first focusing optical fiber, a second focusing optical fiber, a first photoelectric detector, a second photoelectric detector, a signal processing unit and an oscilloscope. An optical port of the semiconductor laser is connected with a first port of the beam splitting and combining device through the focusing lens; a second port of the beam splitting and combining device is connected with a first surface of the first coupling prism; the second surface of the first coupling prism is coupled with the crystal resonant cavity; a third port of the beam splitting and combining device is connected with a first surface of a second coupling prism through a reflecting mirror; and the second surface of the second coupling prism is coupled with the crystal resonant cavity. The problems that an existing random number generator is low in generation rate and the entropy value of generated random numbers is low are solved, and the random number generator is suitable for cryptography, communication systems, numerical simulation, statistical analysis and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optoelectronics, in particular to a random number generator and a generating method based on crystal resonant cavity optical chaos. BACKGROUND

[0002] A random number generator is a device for generating random numbers, which is widely used in the fields of cryptography, communication systems, numerical simulation, statistical analysis, etc. However, in practical applications, the existing random number generator has low generation rate and low entropy value of generated random numbers due to its own principle, and therefore cannot well meet the actual application requirements. Therefore, it is necessary to invent a random number generator and a generating method based on crystal resonant cavity optical chaos to solve the problems of low generation rate and low entropy value of generated random numbers of the existing random number generator. SUMMARY

[0003] The present application provides a random number generator and a generating method based on crystal resonant cavity optical chaos to solve the problems of low generation rate and low entropy value of generated random numbers of the existing random number generator.

[0004] The present application is implemented by using the following technical solutions: A random number generator based on crystal resonant cavity optical chaos, comprising a semiconductor laser, a focusing mirror, a beam splitter-combiner, a reflecting mirror, a first coupling prism, a second coupling prism, a crystal resonant cavity, a first focusing optical fiber, a second focusing optical fiber, a first photodetector, a second photodetector, a signal processing unit, and an oscilloscope. The light port of the semiconductor laser is connected to the first port of the beam splitter-combiner through the focusing mirror. The second port of the beam splitter-combiner is connected to the first face of the first coupling prism; the second face of the first coupling prism is coupled to the crystal resonant cavity; the third face of the first coupling prism is connected to the incident end of the first photodetector through the first focusing optical fiber; the signal output end of the first photodetector is connected to the signal input end of the signal processing unit and the signal input end of the oscilloscope. The third port of the beam splitter-combiner is connected to the first face of the second coupling prism through the reflecting mirror; the second face of the second coupling prism is coupled to the crystal resonant cavity; the third face of the second coupling prism is connected to the incident end of the second photodetector through the second focusing optical fiber; and the signal output end of the second photodetector is connected to the signal input end of the oscilloscope.

[0005] Further, the signal processing unit comprises an analog-digital conversion module, a digital signal processing module, and a randomness enhancement algorithm module; a signal input end of the analog-digital conversion module is used as a signal input end of the signal processing unit; a signal output end of the analog-digital conversion module is connected with a signal input end of the digital signal processing module; a signal output end of the digital signal processing module is connected with a signal input end of the randomness enhancement algorithm module; and a signal output end of the randomness enhancement algorithm module is used as a signal output end of the signal processing unit.

[0006] Further, the device further comprises an air-cooled box and a voltage stabilizing power supply; the semiconductor laser is located in the air-cooled box; and output ends of the voltage stabilizing power supply are connected with a power supply end of the air-cooled box and a power supply end of the semiconductor laser.

[0007] Further, the semiconductor laser has a wavelength of 193 nm or 450 nm or 532 nm or 680 nm or 808 nm or 980 nm or 1064 nm or 1310 nm or 1550 nm; the chip of the semiconductor laser is an FP laser chip or a VCSEL laser chip or a DFB laser chip; and the material of the crystal resonant cavity is calcium fluoride or magnesium fluoride or aluminum oxide or lithium niobate or lithium tantalate.

[0008] Further, the crystal resonant cavity is prepared by the following steps: firstly, a diamond tool is used to perform roundness pre-treatment on an optical crystal material with a rough surface to obtain a disc-shaped optical crystal with a thickness of 0.2 mm and a diameter of 7 mm; and then, the disc-shaped optical crystal is polished by using polishing paper and polishing liquid with roughnesses of 9 nm, 5 nm, 3 nm, 1 nm, 0.5 nm, 0.3 nm, and 0.1 nm in sequence, so that the disc-shaped optical crystal has a surface roughness of less than 1 nm and a diameter of 6.6 mm±0.1 mm, thereby obtaining the crystal resonant cavity.

[0009] A random number generation method based on crystal resonant cavity optical chaos, which is realized based on the random number generator based on crystal resonant cavity optical chaos. Firstly, the random number generator is controlled to enter a working mode; and the working mode is specifically as follows: The light output by the semiconductor laser is incident on a beam splitter-combiner through a focusing mirror, and is divided into two paths of light through the beam splitter-combiner: the first path of light is incident on a first coupling prism and enters the crystal resonant cavity through evanescent field coupling to perform forward propagation; and the second path of light is incident on a second coupling prism through a reflecting mirror and enters the crystal resonant cavity through evanescent field coupling to perform reverse propagation. In the forward propagation process, part of the first light enters the second coupling prism as the first feedback light, and sequentially feedbacks to the semiconductor laser through the second coupling prism, the mirror, the beam splitter and combiner and the focusing lens, thereby interfering with the light output by the semiconductor laser; in the reverse propagation process, part of the second light enters the first coupling prism as the second feedback light, and sequentially feedbacks to the semiconductor laser through the first coupling prism, the beam splitter and combiner and the focusing lens, thereby interfering with the light output by the semiconductor laser; under the joint action of the two feedback lights, the semiconductor laser enters the chaotic state; In the forward propagation process, another part of the first light enters the first coupling prism as the first output light, and sequentially enters the first photodetector through the first coupling prism and the first focusing optical fiber, and then is converted into the first electric signal by the first photodetector and transmitted to the signal processing unit and the oscilloscope; in the reverse propagation process, another part of the second light enters the second coupling prism as the second output light, and sequentially enters the second photodetector through the second coupling prism and the second focusing optical fiber, and then is converted into the second electric signal by the second photodetector and transmitted to the oscilloscope; the signal processing unit generates random numbers after processing the first electric signal; the oscilloscope monitors the two electric signals; In the working mode, the intensity of the second feedback light can be adjusted by adjusting the coupling distance between the first coupling prism and the crystal resonant cavity; the intensity of the first feedback light can be adjusted by adjusting the coupling distance between the second coupling prism and the crystal resonant cavity; the frequency detuning between the semiconductor laser and the crystal resonant cavity can be adjusted by adjusting the intensity of the two feedback lights, thereby adjusting the chaotic state of the semiconductor laser and adjusting the entropy value of the random numbers.

[0010] Further, the processing of the first electric signal by the signal processing unit specifically includes: sampling the first electric signal by an analog-to-digital conversion module, quantizing the first electric signal by a digital signal processing module, and enhancing the randomness of the first electric signal by a randomness enhancement algorithm module.

[0011] Further, in the working mode, the air-cooled box continuously cools the semiconductor laser, and the stabilized power supply continuously supplies power to the air-cooled box and the semiconductor laser.

[0012] Further, in the working mode, the adjustment mode of the coupling distance is three-dimensional displacement table adjustment or PZT stress adjustment or thermal adjustment or electrical adjustment.

[0013] Compared with the existing random number generator, the random number generator and generation method based on crystal resonant cavity optical chaos according to the present application realize efficient and reliable generation of random numbers by adopting a brand-new principle, which significantly improves the generation rate on the one hand and significantly improves the entropy value of the generated random numbers on the other hand, and thus can well meet the actual application requirements.

[0014] The present application effectively solves the problems of low generation rate and low entropy of generated random numbers of the existing random number generator, and is suitable for the fields of cryptography, communication system, numerical simulation, statistical analysis and the like. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a structural schematic diagram of the present application.

[0016] Figure 2 is a partial structural schematic diagram of Figure 1 .

[0017] Figure 3 is a left view of Figure 2 .

[0018] Figure 4 is a structural schematic diagram of the signal processing unit in the present application.

[0019] In the figure: 1-semiconductor laser, 2-focusing mirror, 3-beam splitter and combiner, 4-reflection mirror, 5-first coupling prism, 6-second coupling prism, 7-crystal resonant cavity, 8-first focusing optical fiber, 9-second focusing optical fiber, 10-first photodetector, 11-second photodetector, 12-signal processing unit, 13-analog-to-digital conversion module, 14-digital signal processing module, 15-randomness enhancement algorithm module, 16-oscilloscope, 17-air-cooled box, 18-stabilized power supply. DETAILED DESCRIPTION

[0020] A random number generator based on crystal resonant cavity optical chaos, comprising a semiconductor laser 1, a focusing mirror 2, a beam splitter and combiner 3, a reflection mirror 4, a first coupling prism 5, a second coupling prism 6, a crystal resonant cavity 7, a first focusing optical fiber 8, a second focusing optical fiber 9, a first photodetector 10, a second photodetector 11, a signal processing unit 12, and an oscilloscope 16. The light port of the semiconductor laser 1 is connected with the first port of the beam splitter and combiner 3 through the focusing mirror 2. The second port of the beam splitter and combiner 3 is connected with the first face of the first coupling prism 5; the second face of the first coupling prism 5 is coupled with the crystal resonant cavity 7; the third face of the first coupling prism 5 is connected with the incident end of the first photodetector 10 through the first focusing optical fiber 8; the signal output end of the first photodetector 10 is connected with the signal input end of the signal processing unit 12 and the signal input end of the oscilloscope 16, respectively. The third port of the beam splitting and combining device 3 is connected with the first surface of the second coupling prism 6 through the reflector 4; the second surface of the second coupling prism 6 is coupled with the crystal resonant cavity 7; the third surface of the second coupling prism 6 is connected with the incident end of the second photoelectric detector 11 through the second focusing optical fiber 9; the signal output end of the second photoelectric detector 11 is connected with the signal input end of the oscilloscope 16.

[0021] The signal processing unit 12 comprises an analog-digital conversion module 13, a digital signal processing module 14 and a randomness enhancement algorithm module 15; the signal input end of the analog-digital conversion module 13 serves as the signal input end of the signal processing unit 12; the signal output end of the analog-digital conversion module 13 is connected with the signal input end of the digital signal processing module 14; the signal output end of the digital signal processing module 14 is connected with the signal input end of the randomness enhancement algorithm module 15; the signal output end of the randomness enhancement algorithm module 15 serves as the signal output end of the signal processing unit 12.

[0022] Further comprising an air-cooled box 17 and a voltage stabilizing power supply 18; the semiconductor laser 1 is located in the air-cooled box 17; the output ends of the voltage stabilizing power supply 18 are respectively connected with the power supply end of the air-cooled box 17 and the power supply end of the semiconductor laser 1.

[0023] The wavelength of the semiconductor laser 1 is 193nm or 450nm or 532nm or 680nm or 808nm or 980nm or 1064nm or 1310nm or 1550nm; the chip of the semiconductor laser 1 is an FP (Fabry-Perot) laser chip or a VCSEL (Vertical Cavity Surface Emitting Laser) laser chip or a DFB (Distributed Feedback) laser chip; the material of the crystal resonant cavity 7 is calcium fluoride or magnesium fluoride or aluminum oxide or lithium niobate or lithium tantalate.

[0024] The crystal resonant cavity 7 is prepared by the following steps: firstly, the surface rough optical crystal material is pre-processed by adopting a diamond tool to obtain a disc-shaped optical crystal with a thickness of 0.2mm and a diameter of 7mm; then, the disc-shaped optical crystal is polished by adopting polishing paper and polishing liquid with roughness of 9nm, 5nm, 3nm, 1nm, 0.5nm, 0.3nm and 0.1nm in sequence, so that the surface roughness of the disc-shaped optical crystal is better than 1nm and the diameter is 6.6mm±0.1mm, thereby obtaining the crystal resonant cavity 7.

[0025] A random number generation method based on crystal resonant cavity optical chaos, which is realized based on the random number generator based on crystal resonant cavity optical chaos. Firstly, the random number generator is controlled to enter a working mode; the working mode is specifically: The light outputted by the semiconductor laser 1 is incident to the beam splitter-combiner 3 through the focusing mirror 2, and is divided into two paths of light through the beam splitter-combiner 3: the first path of light is incident to the first coupling prism 5 and is coupled into the crystal resonant cavity 7 through the evanescent field for forward propagation; the second path of light is incident to the second coupling prism 6 through the reflecting mirror 4 and is coupled into the crystal resonant cavity 7 through the evanescent field for backward propagation; In the process of forward propagation, a part of the first path of light enters the second coupling prism 6 as the first path of feedback light, and is fed back to the semiconductor laser 1 through the second coupling prism 6, the reflecting mirror 4, the beam splitter-combiner 3 and the focusing mirror 2 in turn, thereby interfering with the light outputted by the semiconductor laser 1; in the process of backward propagation, a part of the second path of light enters the first coupling prism 5 as the second path of feedback light, and is fed back to the semiconductor laser 1 through the first coupling prism 5, the beam splitter-combiner 3 and the focusing mirror 2 in turn, thereby interfering with the light outputted by the semiconductor laser 1; under the joint action of the two paths of feedback light, the semiconductor laser 1 enters the chaotic state; In the process of forward propagation, another part of the first path of light enters the first coupling prism 5 as the first path of output light, and is incident to the first photodetector 10 through the first coupling prism 5 and the first focusing optical fiber 8 in turn, and then is converted into the first path of electric signal through the first photodetector 10 and is transmitted to the signal processing unit 12 and the oscilloscope 16; in the process of backward propagation, another part of the second path of light enters the second coupling prism 6 as the second path of output light, and is incident to the second photodetector 11 through the second coupling prism 6 and the second focusing optical fiber 9 in turn, and then is converted into the second path of electric signal through the second photodetector 11 and is transmitted to the oscilloscope 16; the signal processing unit 12 generates random numbers after processing the first path of electric signal; the oscilloscope 16 monitors the two paths of electric signal; In the working mode, the intensity of the second path of feedback light can be adjusted by adjusting the coupling distance between the first coupling prism 5 and the crystal resonant cavity 7 (as shown in Figure 2 , d 1 which represents the coupling distance between the first coupling prism 5 and the crystal resonant cavity 7); the intensity of the first path of feedback light can be adjusted by adjusting the coupling distance between the second coupling prism 6 and the crystal resonant cavity 7 (as shown in Figure 2 , d 2 which represents the coupling distance between the second coupling prism 6 and the crystal resonant cavity 7); the frequency detuning between the semiconductor laser 1 and the crystal resonant cavity 7 can be adjusted by adjusting the intensities of the two paths of feedback light, thereby adjusting the chaotic state of the semiconductor laser 1, so as to adjust the entropy value of the random numbers.

[0026] The signal processing unit 12 processes the first electric signal, specifically including: the analog-to-digital conversion module 13 sampling the first electric signal, the digital signal processing module 14 quantizing the first electric signal, and the randomness enhancement algorithm module 15 enhancing randomness of the first electric signal.

[0027] In the working mode, the air-cooled box 17 continuously cools the semiconductor laser 1, and the voltage stabilizing power supply 18 continuously supplies power to the air-cooled box 17 and the semiconductor laser 1.

[0028] In the working mode, the adjustment mode of the coupling distance is three-dimensional displacement table adjustment, PZT (piezoelectric ceramic driver) stress adjustment, thermal adjustment, or electrical adjustment.

[0029] In specific implementation, the first coupling prism 5 and the second coupling prism 6 are both coated with an anti-reflection film. The size of the first coupling prism 5, the size of the second coupling prism 6, the size of the crystal resonant cavity 7, the size of the first focusing optical fiber 8, and the size of the second focusing optical fiber 9 are all determined according to actual application requirements.

[0030] Although the specific embodiments of the present application are described above, those skilled in the art should understand that these are only illustrative, and the protection scope of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present application, and these changes and modifications all fall within the protection scope of the present application.

Claims

1. A random number generator based on optical chaos in a crystalline resonator, characterized in that: It comprises a semiconductor laser (1), a focusing mirror (2), a beam splitter-combiner (3), a reflecting mirror (4), a first coupling prism (5), a second coupling prism (6), a crystal resonant cavity (7), a first focusing optical fiber (8), a second focusing optical fiber (9), a first photodetector (10), a second photodetector (11), a signal processing unit (12), and an oscilloscope (16). The light port of the semiconductor laser (1) is connected with the first port of the beam splitter-combiner (3) through the focusing mirror (2). The second port of the beam splitter-combiner (3) is connected with the first face of the first coupling prism (5); the second face of the first coupling prism (5) is coupled with the crystal resonant cavity (7); the third face of the first coupling prism (5) is connected with the incident end of the first photodetector (10) through the first focusing optical fiber (8); the signal output end of the first photodetector (10) is connected with the signal input end of the signal processing unit (12) and the signal input end of the oscilloscope (16). The third port of the beam splitter-combiner (3) is connected with the first face of the second coupling prism (6) through the reflecting mirror (4); the second face of the second coupling prism (6) is coupled with the crystal resonant cavity (7); the third face of the second coupling prism (6) is connected with the incident end of the second photodetector (11) through the second focusing optical fiber (9); the signal output end of the second photodetector (11) is connected with the signal input end of the oscilloscope (16).

2. The random number generator based on optical chaos in a crystal resonator according to claim 1, characterized in that: The signal processing unit (12) comprises an analog-digital conversion module (13), a digital signal processing module (14), and a randomness enhancement algorithm module (15); the signal input end of the analog-digital conversion module (13) is the signal input end of the signal processing unit (12); the signal output end of the analog-digital conversion module (13) is connected with the signal input end of the digital signal processing module (14); the signal output end of the digital signal processing module (14) is connected with the signal input end of the randomness enhancement algorithm module (15); the signal output end of the randomness enhancement algorithm module (15) is the signal output end of the signal processing unit (12).

3. The random number generator based on optical chaos in a crystal resonator cavity according to claim 1, characterized in that: It further comprises an air-cooled box (17) and a stabilized power supply (18); the semiconductor laser (1) is located in the air-cooled box (17); the output end of the stabilized power supply (18) is connected with the power supply end of the air-cooled box (17) and the power supply end of the semiconductor laser (1).

4. The random number generator based on optical chaos in a crystal resonator cavity according to claim 1, characterized in that: The wavelength of the semiconductor laser (1) is 193 nm or 450 nm or 532 nm or 680 nm or 808 nm or 980 nm or 1064 nm or 1310 nm or 1550 nm; the chip of the semiconductor laser (1) is an FP laser chip or a VCSEL laser chip or a DFB laser chip; the material of the crystal resonant cavity (7) is calcium fluoride or magnesium fluoride or aluminum oxide or lithium niobate or lithium tantalate.

5. The random number generator based on optical chaos in a crystal resonator cavity according to claim 1, characterized in that: The crystal resonant cavity (7) is prepared by the following steps: firstly, the optical crystal material with rough surface is pre-processed by a diamond tool to obtain a disc-shaped optical crystal with a thickness of 0.2 mm and a diameter of 7 mm; then, the disc-shaped optical crystal is polished by polishing paper and polishing liquid with roughness of 9 nm, 5 nm, 3 nm, 1 nm, 0.5 nm, 0.3 nm and 0.1 nm in sequence, so that the surface roughness of the disc-shaped optical crystal is better than 1 nm and the diameter is 6.6 mm±0.1 mm, thereby obtaining the crystal resonant cavity (7).

6. A method for generating random numbers based on optical chaos of a crystal resonant cavity, the method being implemented by the random number generator based on optical chaos of a crystal resonant cavity according to claim 1, characterized in that: The method is realized by the following steps: Firstly, the random number generator is controlled to enter a working mode; the working mode is specifically: The light output by the semiconductor laser (1) is incident on the beam splitter and combiner (3) through the focusing mirror (2), and is divided into two paths of light by the beam splitter and combiner (3): the first path of light is incident on the first coupling prism (5) and enters the crystal resonant cavity (7) through evanescent field coupling for forward propagation; the second path of light is incident on the second coupling prism (6) through the reflecting mirror (4) and enters the crystal resonant cavity (7) through evanescent field coupling for reverse propagation; In the forward propagation process, part of the first path of light enters the second coupling prism (6) as the first feedback light, and is fed back to the semiconductor laser (1) in sequence through the second coupling prism (6), the reflecting mirror (4), the beam splitter and combiner (3) and the focusing mirror (2), thereby interfering with the light output by the semiconductor laser (1); In the reverse propagation process, part of the second path of light enters the first coupling prism (5) as the second feedback light, and is fed back to the semiconductor laser (1) in sequence through the first coupling prism (5), the beam splitter and combiner (3) and the focusing mirror (2), thereby interfering with the light output by the semiconductor laser (1); under the joint action of the two paths of feedback light, the semiconductor laser (1) enters a chaotic state; In the forward propagation process, another part of the first path of light enters the first coupling prism (5) as the first output light, and is incident on the first photoelectric detector (10) in sequence through the first coupling prism (5) and the first focusing optical fiber (8), and then is converted into the first electric signal by the first photoelectric detector (10) and transmitted to the signal processing unit (12) and the oscilloscope (16); in the reverse propagation process, another part of the second path of light enters the second coupling prism (6) as the second output light, and is incident on the second photoelectric detector (11) in sequence through the second coupling prism (6) and the second focusing optical fiber (9), and then is converted into the second electric signal by the second photoelectric detector (11) and transmitted to the oscilloscope (16); the signal processing unit (12) processes the first electric signal to generate a random number; the oscilloscope (16) monitors the two electric signals; In the working mode, the intensity of the second feedback light can be adjusted by adjusting the coupling distance between the first coupling prism (5) and the crystal resonant cavity (7); the intensity of the first feedback light can be adjusted by adjusting the coupling distance between the second coupling prism (6) and the crystal resonant cavity (7); the frequency detuning between the semiconductor laser (1) and the crystal resonant cavity (7) can be adjusted by adjusting the intensity of the two feedback lights, thereby adjusting the chaotic state of the semiconductor laser (1) and adjusting the entropy value of the random number.

7. The method of claim 6, wherein the method is based on optical chaos in a crystal resonator. The signal processing unit (12) processes the first electric signal, and the processing specifically includes: an analog-to-digital conversion module (13) sampling the first electric signal, a digital signal processing module (14) quantizing the first electric signal, and a randomness enhancement algorithm module (15) enhancing the randomness of the first electric signal.

8. The method of claim 6, wherein the method is based on optical chaos in a crystal resonator. In the working mode, the air-cooled box (17) continuously cools the semiconductor laser (1), and the voltage stabilizing power supply (18) continuously supplies power to the air-cooled box (17) and the semiconductor laser (1).

9. The method of claim 6, wherein the method is based on optical chaos in a crystal resonator. In the working mode, the adjustment mode of the coupling distance is three-dimensional displacement table adjustment or PZT stress adjustment or thermal adjustment or electrical adjustment.

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