Optical storage information parallel reading optical system and method

Abstract

The invention discloses an optical storage information parallel reading optical system which comprises a uniform light illumination module, an optical crosstalk elimination module, a segmentation area module and a wavelength spectroscope arranged between a first collimating mirror and an energy spectroscope. Emitting a light beam to the energy spectroscope so as to provide a uniform illumination light source for a plurality of optical disc information points on the optical disc to be read and generate diffuse reflection to form information light with optical disc information crosstalk; an optical crosstalk elimination module is used for processing information light, performing crosstalk elimination on adjacent information points to obtain a plurality of crosstalk-eliminated information light, and imaging the crosstalk-eliminated information to a photoelectric conversion device PDIC to realize parallel reading of optical storage information. The problem that a traditional optical storage reading method is low in reading efficiency is solved.

Description

Technical Field

[0001] This invention relates to the field of high-capacity optical storage technology, and in particular to an optical system and method for parallel reading of optical storage information. Background Technology

[0002] The rapid development of big data and artificial intelligence technologies has led to severe bottlenecks in energy consumption, capacity, and lifespan for traditional magnetic storage-based big data storage technologies. In recent years, the amount of data generated worldwide has increased dramatically, and the demand for high-capacity storage has also gradually increased. High-capacity optical storage, with its low storage costs, low power consumption, and long lifespan, is highly anticipated as the next generation of mainstream data storage systems.

[0003] The principle of current traditional optical storage and retrieval methods is as follows: Figure 3 As shown, the laser beam emitted by laser LD_1 is collimated into parallel light by collimation diameter CL_1, passes through the energy beam splitter (reflecting and transmitting light energy proportionally), and is focused onto the information point on the optical disc by the first objective lens OL_1. The focused light diffusely reflected from the information point is reversibly converted into parallel light by the first objective lens OL_1, reflected by the energy beam splitter, and then focused onto the photoelectric conversion device PDIC by the imaging objective lens OL_2, completing the reading of one information point. Because the reflectivity of the material recording information points and the material not recording information points are different, the energy received by the PDIC is different, thus distinguishing 0 and 1. However, this sequential reading method of optical storage can only read one piece of information at a time, limiting the read and write speed. Summary of the Invention

[0004] This invention provides an optical system and method for parallel reading of optical storage information to overcome the above-mentioned technical problems.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: An optical system for parallel reading of optical storage information includes a basic optical module consisting of a first laser, a first collimating lens, an energy beam splitter, a first objective lens, and an optical disc to be read, arranged sequentially at intervals. It also includes a uniform illumination module, an optical crosstalk reduction module, a segmentation module, and a wavelength beam splitter disposed between the first collimating lens and the energy beam splitter. The uniform illumination module is used to emit a beam of light to the energy beam splitter during optical storage information reading to provide a uniform illumination source for multiple optical disc information points on the optical disc to be read and to cause diffuse reflection, thereby forming information light with optical disc information crosstalk. The optical crosstalk cancellation module is used to cancel crosstalk between adjacent information points in the processed information light to obtain several crosstalk-cancelled information lights; and the processed information light is the information light with optical disc information crosstalk that passes through the energy beam splitter and the wavelength beam splitter in sequence. The segmentation module is used to divide the imaging area of ​​the photoelectric conversion device PDIC into segmentation areas equal to the number of information points on the optical disc, based on the number of information points covered by the illumination source. This allows the crosstalk-eliminating information light to be imaged onto each segmentation area through the second objective lens, thereby enabling parallel reading of optical storage information.

[0006] Furthermore, the uniform illumination module includes a second laser, a second collimating lens, and a grating uniform illumination module; The second laser is used to emit a Gaussian light source to the second collimating lens; The second collimating lens is used to collimate the Gaussian light source into parallel light; The grating homogenizing module is used to divide parallel light into n beams of light, which is the same as the number of grating lines, and the Gaussian energy of each beam of light is different and the energy is uniformly distributed in each beam.

[0007] Furthermore, the grating uniform light module includes a first grating and a second grating whose grating directions are perpendicular to each other and spaced apart.

[0008] Furthermore, the optical crosstalk cancellation module is a holographic phase sheet group structure consisting of several holographic phase sheets spaced apart along the optical axis, so as to suppress crosstalk generated by adjacent information points on the optical disc along different spatial orientations through the holographic phase sheet group structure.

[0009] Furthermore, the optical disc to be read is positioned on the rear focal plane of the first objective lens; The line connecting the second laser, the second collimating lens, and the center point of the grating homogenizing module in the grating homogenizing module is perpendicular to the line connecting the optical axis between the energy beam splitter and the first objective lens.

[0010] A method for parallel reading of optical storage information includes the following steps: S100: A Gaussian light source is emitted from the first laser to the second collimating lens, and the second collimating lens collimates the Gaussian light source into first parallel light. A portion of the first parallel light beam is transmitted to the energy beam splitter through the wavelength beam splitter. Simultaneously, a Gaussian light source is emitted from the second laser to the second collimating lens, and the second collimating lens collimates the Gaussian light source into second parallel light. The second parallel light beam is split into n beams of light, the same number as the number of grating lines, through the grating homogenizing module. The n beams of light, together with a portion of the first parallel light beam that passes through the energy beam splitter, are transmitted to the first objective lens, and a uniformly distributed illumination source is formed through the first objective lens; S101: The optical disc to be read is placed on the focal plane of the first objective lens to provide a uniform illumination source for multiple optical disc information points on the optical disc to be read and to cause diffuse reflection, forming information light with optical disc information crosstalk, and transmitting it in reverse to the energy beam splitter. S102: A portion of the information light beam with optical disc information crosstalk that has passed through the energy beam splitter is reversed and transmitted to the wavelength beam splitter to obtain the processed information light. The crosstalk between adjacent information points of the processed information light is eliminated by the optical crosstalk elimination module to obtain a number of crosstalk-eliminated information lights. S103: The crosstalk-eliminating information light is imaged through the second objective lens onto the segmented regions after the imaging area of ​​the photoelectric conversion device PDIC is divided equally, thereby realizing the parallel reading of optical storage information.

[0011] Beneficial effects: This invention provides an optical system and method for parallel reading of optical storage information. During optical storage information reading, a uniform illumination module emits a beam of light towards an energy beam splitter to provide uniform illumination for multiple information points on the optical disc to be read, resulting in diffuse reflection and forming information light with optical disc information crosstalk. An optical anti-crosstalk module is used to process the information light, eliminating crosstalk between adjacent information points to obtain several crosstalk-eliminated information lights. The crosstalk-eliminated information is then imaged onto a photoelectric conversion device (PDIC), achieving parallel reading of optical storage information and significantly improving the reading efficiency of optical storage information. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram of the optical system for parallel reading of optical storage information according to the present invention; Figure 2 This is a schematic diagram of the optical system for parallel reading of optical storage information in this embodiment; Figure 3 This is a schematic diagram of the traditional optical storage and retrieval method in this embodiment. Detailed Implementation

[0014] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0015] This embodiment provides an optical system for parallel reading of optical stored information, such as... Figures 1 to 2As shown, it includes a basic optical module consisting of a first laser, a first collimating lens, an energy beam splitter, a first objective lens, and a disc to be read, arranged sequentially at intervals. It also includes a uniform illumination module, an optical crosstalk cancellation module, a segmentation module, and a wavelength beam splitter disposed between the first collimating lens and the energy beam splitter. The uniform illumination module is used to emit a beam of light to the energy beam splitter during optical storage information reading to provide a uniform illumination source for multiple optical disc information points on the optical disc to be read and to cause diffuse reflection, thereby forming information light with optical disc information crosstalk. Specifically, the uniform illumination module includes a second laser, a second collimating lens, and a grating uniform illumination module. The second laser emits a Gaussian light source to the second collimating lens. The second collimating lens collimates the Gaussian light source into parallel light. The grating uniform illumination module divides the parallel light into n beams, the same number of grating lines as the number of grating lines. The Gaussian energies of each of the n beams are different, and the energy within each beam is uniformly distributed. The grating uniform illumination module includes a first grating and a second grating, whose grating lines are perpendicular to each other and spaced apart. The straight line connecting the center point of the second laser, the second collimating lens, and the grating uniform illumination module is perpendicular to the straight line connecting the optical axis between the energy beam splitter and the first objective lens. The optical path of the uniform illumination module in this embodiment is as follows: ①: The divergent Gaussian light emitted by the laser source LD_2, i.e. the second laser, is collimated into parallel light after passing through the collimating lens CL_2, i.e. the second collimating lens; ②: After collimation, the parallel light source passes through a grating homogenization system with the gratings placed perpendicularly to the gratings, i.e., the grating homogenization module (gratings _1 and _2 with the gratings placed perpendicular to each other). The Gaussian beam is divided into n beams with the same number of grating gratings. Each beam intercepts a different position of the Gaussian light source, which means that each beam has a different energy. Each beam also contains m diffraction orders. ③: After n beams of light are converged by the objective lens, each beam of light is arranged on the focal plane of the objective lens according to the same diffraction order. That is, the light of the Gaussian beams at different positions is superimposed on the focal plane of the objective lens, forming a uniformly distributed illumination surface light on the focal plane of the objective lens. ④: Place the disc to be read on the focal plane of the objective lens so that the multiple information points on the disc are evenly illuminated; The optical crosstalk cancellation module is used to cancel crosstalk between adjacent information points in the processed information light to obtain several crosstalk-cancelled information lights; and the processed information light is the information light with optical disc information crosstalk that passes through the energy beam splitter and the wavelength beam splitter in sequence; specifically, the optical crosstalk cancellation module is a holographic phase sheet group structure consisting of several holographic phase sheets spaced along the optical axis, so as to suppress the crosstalk generated by adjacent information points along different spatial orientations on the optical disc through the holographic phase sheet group structure; The segmentation module is used to divide the imaging area of ​​the photoelectric conversion device PDIC into equal segments based on the number of information points on the optical disc covered by the illumination source. This allows the crosstalk-eliminating information light to be imaged onto each segmented segment via the second objective lens, thereby achieving parallel reading of optically stored information. In this embodiment, multiple information points covered by the illumination source undergo diffuse reflection. The diffusely reflected light carries the information from these points. Because it is diffuse reflection, crosstalk occurs between the information points. The crosstalk-laden information light passes through an energy beam splitter and a wavelength beam splitter before being incident on a pre-modulated holographic phase plate group to eliminate crosstalk between adjacent information points. The information points with eliminated two-dimensional crosstalk are imaged onto the photoelectric conversion device PDIC by the second objective lens OL_2. Corresponding to the number of information points read in a single operation, the photoelectric conversion device PDIC will have the same number of segmented segments. Each segmented segment of the photoelectric conversion device PDIC corresponds to one information point. Because the reflectivity of recorded information 1 and 0 is different, the light energy in the segmented segments of the photoelectric conversion device PDIC will also have varying strengths, thus achieving parallel reading in a single operation.

[0016] This embodiment adds a surface lighting system to the existing reading system. To enable the wavelength splitter to easily achieve beam splitting, the laser light source used in the lighting system must have a different wavelength than the writing laser light source. For example, if the writing laser wavelength is 405nm, then the lighting wavelength can be a laser above 450nm. Figure 2 The grating is placed on the front focal plane of the first objective lens OL_1, and the optical disc is placed on the rear focal plane of the first objective lens OL_1. According to the imaging characteristics of optical lenses, the diffracted light of each order is emitted in parallel after passing through the first objective lens OL_1. The same order converges to the same position on the focal plane. Therefore, the illumination range depends on the diffraction angle and the focal length of the objective lens. For example, if the focal length of the objective lens is f=2mm, since the diffracted light energy is mainly concentrated in the 0th and ±1st orders, the diffraction angle can be considered only for the 1st order. For example, the 1st order diffraction angle θ=1.43°, and the coverage area can be calculated as tan(θ)×f=tan(1.43)×2=50μm, and the area S1=50×50=2500μm^2. For a 25GB BD optical disc, the area of ​​a single information point is S2=0.15×0.32=0.048μm^2. Therefore, the number of information points that can be illuminated at one time is n=2500÷0.048=52Kb. In this embodiment, reading 52Kb of data in parallel at once would require an astonishing amount of computation if traditional electronic decoding were used, making it unsuitable for commercial optical storage. This embodiment utilizes optical anti-crosstalk decoding technology. Single-point sequential reading results in one-dimensional crosstalk, while parallel reading results in two-dimensional crosstalk. A set of holographic phase plates is inserted between the wavelength beam splitter and the second objective lens OL_2 of the PDIC, which can eliminate two-dimensional crosstalk between information points and directly output crosstalk-free optical information. The PDIC then performs photoelectric conversion to complete one parallel reading.

[0017] A method for parallel reading of optical storage information includes the following steps: S100: A Gaussian light source is emitted from the first laser to the second collimating lens, and the second collimating lens collimates the Gaussian light source into first parallel light. A portion of the first parallel light beam is transmitted to the energy beam splitter through the wavelength beam splitter. Simultaneously, a Gaussian light source is emitted from the second laser to the second collimating lens, and the second collimating lens collimates the Gaussian light source into second parallel light. The second parallel light beam is split into n beams of light, the same number as the number of grating lines, through the grating homogenizing module. The n beams of light, together with a portion of the first parallel light beam that passes through the energy beam splitter, are transmitted to the first objective lens, and a uniformly distributed illumination source is formed through the first objective lens; S101: The optical disc to be read is placed on the focal plane of the first objective lens to provide a uniform illumination source for multiple optical disc information points on the optical disc to be read and to cause diffuse reflection, forming information light with optical disc information crosstalk, and transmitting it in reverse to the energy beam splitter. S102: A portion of the information light beam with optical disc information crosstalk that has passed through the energy beam splitter is reversed and transmitted to the wavelength beam splitter to obtain the processed information light. The crosstalk between adjacent information points of the processed information light is eliminated by the optical crosstalk elimination module to obtain a number of crosstalk-eliminated information lights. S103: The crosstalk-eliminating information light is imaged through the second objective lens onto the segmented regions after the imaging area of ​​the photoelectric conversion device PDIC is divided equally, thereby realizing the parallel reading of optical storage information.

[0018] The beneficial effects of the system and method described in this embodiment are as follows: When reading optical storage information, the constructed uniform illumination module emits a beam of light to the energy beam splitter to provide a uniform illumination source for multiple optical disc information points on the optical disc to be read and causes diffuse reflection, forming information light with optical disc information crosstalk; the optical anti-crosstalk module is used to process the information light, eliminate crosstalk between adjacent information points to obtain several crosstalk-eliminated information lights, and image the crosstalk-eliminated information onto the photoelectric conversion device PDIC, realizing parallel reading of optical storage information and greatly improving the reading efficiency of optical storage information.

[0019] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An optical system for parallel reading of optical storage information, comprising a basic optical module consisting of a first laser, a first collimating lens, an energy beam splitter, a first objective lens, and an optical disc to be read, arranged sequentially at intervals, characterized in that, It also includes a uniform illumination module, an optical crosstalk cancellation module, a segmentation module, and a wavelength beam splitter located between the first collimating lens and the energy beam splitter; The uniform illumination module is used to emit a beam of light to the energy beam splitter during optical storage information reading to provide a uniform illumination source for multiple optical disc information points on the optical disc to be read and to cause diffuse reflection, thereby forming information light with optical disc information crosstalk. The optical crosstalk cancellation module is used to cancel crosstalk between adjacent information points in the processed information light to obtain several crosstalk-cancelled information lights; and the processed information light is the information light with optical disc information crosstalk that passes through the energy beam splitter and the wavelength beam splitter in sequence. The segmentation module is used to divide the imaging area of ​​the photoelectric conversion device PDIC into segmentation areas equal to the number of information points on the optical disc, based on the number of information points covered by the illumination source. This allows the crosstalk-eliminating information light to be imaged onto each segmentation area through the second objective lens, thereby enabling parallel reading of optical storage information.

2. The optical system for parallel reading of optical storage information according to claim 1, characterized in that, The uniform illumination module includes a second laser, a second collimating lens, and a grating uniform illumination module. The second laser is used to emit a Gaussian light source to the second collimating lens; The second collimating lens is used to collimate the Gaussian light source into parallel light; The grating homogenizing module is used to divide parallel light into n beams of light, which is the same as the number of grating lines. Furthermore, the Gaussian energies of the beams in the n beams are different, and the energy within each beam is uniformly distributed.

3. The optical system for parallel reading of optical storage information according to claim 2, characterized in that, The grating homogenizing module includes a first grating and a second grating whose grating directions are perpendicular to each other and spaced apart.

4. The optical system for parallel reading of optical storage information according to claim 3, characterized in that, The optical crosstalk cancellation module is a holographic phase sheet group structure consisting of several holographic phase sheets spaced apart along the optical axis, which suppresses crosstalk generated by adjacent information points on the optical disc along different spatial orientations through the holographic phase sheet group structure.

5. The optical system for parallel reading of optical storage information according to claim 4, characterized in that, The optical disc to be read is positioned on the back focal plane of the first objective lens; The line connecting the second laser, the second collimating lens, and the center point of the grating homogenizing module in the grating homogenizing module is perpendicular to the line connecting the optical axis between the energy beam splitter and the first objective lens.

6. A method for parallel reading of optical information based on the optical storage system of claim 5, characterized in that, Includes the following steps: S100: A Gaussian light source is emitted from the first laser to the second collimating lens, and the second collimating lens collimates the Gaussian light source into first parallel light. A portion of the first parallel light beam is transmitted to the energy beam splitter through the wavelength beam splitter. Simultaneously, a Gaussian light source is emitted from the second laser to the second collimating lens, and the second collimating lens collimates the Gaussian light source into second parallel light. The second parallel light beam is split into n beams of light, the same number as the number of grating lines, through the grating homogenizing module. The n beams of light, together with a portion of the first parallel light beam that passes through the energy beam splitter, are transmitted to the first objective lens, and a uniformly distributed illumination source is formed through the first objective lens; S101: The optical disc to be read is placed on the focal plane of the first objective lens to provide a uniform illumination source for multiple optical disc information points on the optical disc to be read and to cause diffuse reflection, forming information light with optical disc information crosstalk, and transmitting it in reverse to the energy beam splitter. S102: A portion of the information light beam with optical disc information crosstalk that has passed through the energy beam splitter is reversed and transmitted to the wavelength beam splitter to obtain the processed information light. The crosstalk between adjacent information points of the processed information light is eliminated by the optical anti-crosstalk module to obtain a number of crosstalk-eliminated information lights. S103: The crosstalk-eliminating information light is imaged through the second objective lens onto the segmented regions after the imaging area of ​​the photoelectric conversion device PDIC is divided equally, thereby realizing the parallel reading of optical storage information.

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