Laser holographic processing device

Abstract

The application provides a laser holographic processing device, comprising: a spatial light modulator arranged in a laser light path, the spatial light modulator being used for modulating a laser beam to form a first modulated light beam; a modulation element arranged in a propagation path of the first modulated light beam, the modulation element comprising a substrate and a conical hole arranged on the substrate, the radius and the depth of the conical hole being in a first curve, a second curve or a high-order nonlinear curve relationship; and a multi-degree-of-freedom bearing platform used for bearing the modulation element and driving the modulation element to translate and / or rotate in multiple directions. The laser holographic processing device provided by the application can effectively balance the durability and the functional integration characteristics by optimizing the quality of the laser beam through the spatial light modulator and modulating the conical hole in different positions and postures.

Description

Technical Field

[0001] This invention relates to the field of laser processing technology, and in particular to a laser holographic processing device. Background Technology

[0002] In cutting-edge technologies such as photonics, precision manufacturing, and sensing, dynamic and precise control of light beams is fundamental to realizing the core functions of a system. Whether it's light field and holographic technology used for 3D imaging and display, or advanced systems applied to laser micro-nano fabrication, optical tweezers manipulation, and free-space optical communication, performance improvements highly depend on real-time, programmable control of one or more dimensions of the light beam, such as intensity, phase, polarization, focal length, spot morphology, and propagation direction. Currently, there are two main approaches to light beam control: one is to increase the complexity and performance of programmable optical elements (such as SLMs) to simplify the associated mechanical motion systems; the other is to use passive optical elements as beam splitters or spatial filters. Based on these two approaches, the existing technological system presents a dilemma: on the one hand, there are simple, robust, and durable passive optical devices, but their functional dimensions are severely limited; on the other hand, there are powerful and highly integrated programmable optical devices, but they have shortcomings in terms of power, accuracy, cost, and spectral adaptability. Due to the characteristics of the two optical devices, existing beam control technologies cannot simultaneously achieve both durability and multifunctional integration, which severely restricts the development of beam control technology. Summary of the Invention

[0003] The laser holographic processing device provided by the present invention can optimize the quality of the laser beam by using a spatial light modulator and then use a conical aperture to modulate it at different positions and orientations, effectively balancing durability and functional integration.

[0004] This invention provides a laser holographic processing device, comprising:

[0005] A spatial light modulator is disposed in the laser optical path and is used to modulate the laser beam to form a first modulated beam.

[0006] A modulation element is disposed in the propagation path of the first modulation beam. The modulation element includes a substrate and a tapered hole disposed on the substrate. The radius and depth of the tapered hole are related by a first-order curve, a second-order curve, or a higher-order nonlinear curve.

[0007] A multi-degree-of-freedom support platform is provided for supporting the modulation element and driving the modulation element to translate and / or rotate in multiple directions.

[0008] Optionally, the substrate is formed using fused silica, sapphire, ceramic, silicon, or a highly reflective metallic material.

[0009] Optionally, the modulation element has a single conical hole, or the modulation element has multiple conical holes arranged in an array.

[0010] Optionally, the multi-degree-of-freedom bearing platform has translational and rotational degrees of freedom in three mutually perpendicular directions.

[0011] Optionally, the laser holographic processing apparatus further includes:

[0012] A holographic lens is disposed in the optical path of the first modulated beam. The holographic lens is used to collimate the first modulated beam so that the collimated first modulated optical path is incident on the modulation element.

[0013] Optionally, the laser holographic processing apparatus further includes:

[0014] A central control unit is communicatively connected to the multi-degree-of-freedom support platform. The central control unit is used to send drive signals to the multi-degree-of-freedom support platform to make the multi-degree-of-freedom platform translate and / or rotate in multiple directions, thereby realizing the modulation of multiple light spot parameters by the conical aperture.

[0015] Optionally, the central control unit includes:

[0016] A controller, which receives user requests and loads corresponding optical modulation target parameters based on the user requests;

[0017] An algorithm module, which is communicatively connected to the controller, is used to analyze the optical modulation target parameters and generate displacement trajectory planning commands.

[0018] A motion control card is communicatively connected to the algorithm module. The motion control card is used to receive the displacement trajectory planning command and send drive signals to the multi-degree-of-freedom bearing platform according to the displacement trajectory planning command.

[0019] Optionally, the tapered aperture is a through hole, so that at least a portion of the laser beam is transmitted through the tapered aperture to modulate the laser beam; or, the tapered aperture diffracts the laser beam to modulate the laser beam.

[0020] Optionally, the conical aperture is a blind aperture, so that the laser beam is received at the open end of the conical aperture, reflected by the sidewall of the conical aperture, and emitted from the open end of the conical aperture, thus completing the modulation of the laser beam.

[0021] Optionally, the tapered hole is formed by femtosecond laser etching, diamond turning, or molding technology.

[0022] In the technical solution provided by this invention, the laser beam is first pre-modulated by a spatial light modulator, and then the first modulated beam is incident on a modulation element with a conical aperture for secondary modulation. Since the modulation element has multiple degrees of freedom, continuous adjustment of multi-dimensional parameters such as the intensity, focus position, wavefront shape, and propagation direction of the first modulated beam can be achieved. Because the main modulation process is performed by the modulation element, which is a passive optical device, the spatial light modulator only needs to provide the modulation element with a first modulated beam of excellent spatial quality and a flat wavefront. Therefore, the operational burden of the spatial light modulator is effectively reduced, ensuring the durability of the entire device. Simultaneously, because the modulation element has a conical aperture and can move in multiple degrees of freedom, spatial modulation of the incident beam intensity, dynamic control of the wavefront curvature (equivalent focal length adjustment), transformation of the beam shape (e.g., from Gaussian to ring or Bessel shape), and fine deflection of the propagation direction can be achieved, realizing the integration of multiple functions. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of a laser holographic processing device according to an embodiment of the present invention;

[0024] Figure 2 This is a schematic diagram of a laser holographic processing device according to another embodiment of the present invention. Detailed Implementation

[0025] 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, and 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.

[0026] This invention provides a laser holographic processing device, such as... Figure 1 and Figure 2 As shown, it includes:

[0027] A spatial light modulator (SLM) is disposed in the laser optical path and is used to modulate the laser beam to form a first modulated beam.

[0028] In some embodiments, the spatial light modulator (SLM) modulates the laser beam solely for optimizing the spatial quality of the laser beam, etc., to facilitate subsequent modulation of the first modulated beam by the modulation element. The laser beam may be emitted from a continuous-wave laser, a pulsed laser, or an ultrafast laser, and its wavelength should cover the ultraviolet, visible, and infrared bands.

[0029] A modulation element is disposed in the propagation path of the first modulation beam. The modulation element includes a substrate and a tapered hole disposed on the substrate. The radius and depth of the tapered hole are related by a first-order curve, a second-order curve, or a higher-order nonlinear curve.

[0030] In some embodiments, when the first modulated beam is directed toward the conical aperture modulation element, its propagation path is affected by the geometry of the conical aperture, resulting in reflection, focusing, or deformation within the aperture wall. By controlling the cone angle, aperture depth, and aperture wall curvature at the incident position, the system can achieve spatial modulation of the incident beam intensity, dynamic control of the wavefront curvature (equivalent focal length adjustment), transformation of the beam spot shape (e.g., from Gaussian to ring or Bezier), and fine deflection of the propagation direction. Control of the cone angle, aperture depth, and aperture wall curvature at the incident position can be achieved through the motion of a multi-degree-of-freedom platform. To enhance the wavefront modulation capability of the conical aperture, the aperture wall can be designed as a linear profile or a nonlinear surface of revolution (e.g., a parabola, hyperboloid, or Gaussian surface), and precision polished to obtain high-quality internal reflection or transmission characteristics. The conical aperture can be a single aperture or form an array structure to achieve parallel control of multiple beams.

[0031] A multi-degree-of-freedom support platform is provided for supporting the modulation element and driving the modulation element to translate and / or rotate in multiple directions.

[0032] In some embodiments, the inner wall configuration of the conical aperture is specifically designed to accommodate modulation requirements for multiple wavebands, various incident angles, and different sizes of light spots. The controllability is independent of material properties or response mechanisms, thereby significantly improving the system's spectral adaptability and stable operation performance. Through the movement of a multi-degree-of-freedom displacement platform, the conical aperture element can be flexibly adjusted in spatial position and orientation, allowing different positions on the inner wall of the conical aperture to receive the first modulated beam. This enables continuous and controllable multi-dimensional modulation of the incident beam's intensity, focal position, wavefront morphology, propagation direction, and other optical properties.

[0033] In the technical solution provided in this embodiment of the invention, the laser beam is first pre-modulated by a spatial light modulator (SLM), and then the first modulated beam is incident on a modulation element with a conical aperture for secondary modulation. Since the modulation element has multiple degrees of freedom, continuous adjustment of multi-dimensional parameters such as the intensity, focus position, wavefront shape, and propagation direction of the first modulated beam can be achieved. Because the main modulation process is performed by the modulation element, which is a passive optical device, the SLM only needs to provide the modulation element with a first modulated beam of excellent spatial quality and a flat wavefront. Therefore, the operational burden of the SLM is effectively reduced, ensuring the durability of the entire device. Simultaneously, because the modulation element has a conical aperture and can move in multiple degrees of freedom, spatial modulation of the incident beam intensity, dynamic control of the wavefront curvature (equivalent focal length adjustment), transformation of the beam shape (e.g., from Gaussian to ring or Bessel shape), and fine deflection of the propagation direction can be achieved, realizing the integration of multiple functions.

[0034] As an alternative implementation, the substrate is formed using fused silica, sapphire, ceramic, silicon, or a highly reflective metallic material.

[0035] In some embodiments, the modulation element is a core optical actuator that needs to be mounted on a high-optical-quality substrate. The substrate material can be fused silica, sapphire, ceramic, or silicon, and can be selected as a transmissive through-hole configuration or a reflective blind-hole configuration depending on the application. Because the aforementioned materials possess high laser damage thresholds and thermal stability, they are suitable for various laser applications such as continuous wave, pulsed laser, and high-energy laser. The conical hole can be, for example, a frustum-shaped structure formed by femtosecond laser etching, diamond turning, or molding techniques, and has key geometric parameters such as inlet port diameter D1, outlet port diameter D2, hole depth L, and cone angle α.

[0036] As an alternative implementation, the modulation element has a single conical hole, or the modulation element has multiple conical holes arranged in an array.

[0037] In some embodiments, through array design, multiple modulation elements can be integrated onto the same platform to achieve parallel control of multi-channel beams, suitable for applications such as programmable light field generation, spatial multi-point laser processing, and multifocal microscopy. In the conical aperture array structure, each conical aperture can be independently or collaboratively adjusted in position and orientation. For example, multiple modulation units can be arranged in an array to form modulation elements, each modulation unit having a conical aperture, and the multi-degree-of-freedom platform can independently adjust the position and orientation of each modulation unit. Using this approach, combined with different beam input paths, spatial reconstruction, homogenization shaping, or dynamic scheduling of the beam array can be achieved, further expanding the system's applicability in high-end applications such as multi-beam parallel processing and programmable light field generation. By calling preset schemes and adjusting online parameters, it can be easily integrated into the main control system, forming an open optical control platform with strong compatibility and a clear upgrade path.

[0038] As an optional implementation, the multi-degree-of-freedom bearing platform has translational and rotational degrees of freedom in three mutually perpendicular directions.

[0039] In some embodiments, the modulation element is mounted on the high-precision multi-degree-of-freedom support platform to achieve precise position and attitude adjustment of the modulation element in three-dimensional space. The multi-degree-of-freedom support platform includes at least linear translational degrees of freedom along the X, Y, and Z axes, and can be further extended to pitch and yaw rotational degrees of freedom around the X, Y, and Z axes as needed, forming a five-axis or six-axis linkage platform. The driving method for the multi-degree-of-freedom support platform can be piezoelectric ceramics, servo motors, or other micro-actuators. The overall positioning accuracy of the system is better than 1 μm, and the repeatability positioning accuracy can reach the sub-micron level, ensuring that the interaction between the beam and the tapered aperture modulation element remains highly consistent.

[0040] As an optional implementation, the laser holographic processing apparatus further includes:

[0041] A holographic lens is disposed in the optical path of the first modulated beam. The holographic lens is used to collimate the first modulated beam so that the collimated first modulated optical path is incident on the modulation element.

[0042] In some embodiments, a holographic lens is used to collimate the first modulated beam to form a wavefront-flat beam, ensuring that the first modulated beam has a uniform power distribution and an appropriate spot size.

[0043] As an optional implementation, the laser holographic processing apparatus further includes:

[0044] A central control unit is communicatively connected to the multi-degree-of-freedom support platform. The central control unit is used to send drive signals to the multi-degree-of-freedom support platform to make the multi-degree-of-freedom platform translate and / or rotate in multiple directions, thereby realizing the modulation of multiple light spot parameters by the conical aperture.

[0045] In some embodiments, the central control unit serves as the control hub of the entire device and can be composed of an industrial computer, an embedded controller, or an FPGA system. The central control unit embeds a computational engine based on geometric optics and wave optics models. It can calculate the required spatial position and angle of the cone-shaped element in real time based on user-defined beam modulation target parameters (such as power, focal length, and spot shape) and the actual measured state of the system, and generate drive signals to control the displacement system to complete the corresponding adjustments. By cooperating with a sensor feedback system, the control unit can achieve open-loop or closed-loop control modes, ensuring modulation accuracy and system stability. During use, after the system is powered on, the central control unit first loads the corresponding optical modulation target parameters according to the user-input functional requirements and calls the built-in physical modeling module for parameter analysis and calculation. Based on the analysis results, the system generates a displacement trajectory planning command and converts it into a drive signal through a motion control card, transmitting it to the high-precision multi-degree-of-freedom bearing platform to achieve spatial positioning of the modulation element.

[0046] As an optional implementation, the central control unit includes:

[0047] A controller, which receives user requests and loads corresponding optical modulation target parameters based on the user requests;

[0048] An algorithm module, which is communicatively connected to the controller, is used to analyze the optical modulation target parameters and generate displacement trajectory planning commands.

[0049] A motion control card is communicatively connected to the algorithm module. The motion control card is used to receive the displacement trajectory planning command and send drive signals to the multi-degree-of-freedom bearing platform according to the displacement trajectory planning command.

[0050] As an optional implementation, the tapered aperture is a through hole, so that at least a portion of the laser beam is transmitted through the tapered aperture to modulate the laser beam; or, the tapered aperture diffracts the laser beam to modulate the laser beam.

[0051] As an optional implementation, the tapered aperture is a blind aperture, so that the laser beam is received at the open end of the tapered aperture, the laser beam is reflected by the sidewall of the tapered aperture, and then emitted from the open end of the tapered aperture, thus completing the modulation of the laser beam.

[0052] As an alternative implementation, the tapered hole is formed using femtosecond laser etching, diamond turning, or molding techniques.

[0053] In some embodiments, the modulation element can be processed by femtosecond laser etching, diamond turning, precision molding, etc., while the displacement system can use existing modular components. Both have good batch consistency and process maturity, facilitating industrial mass production and platform deployment. The overall structure of the device is compact and the assembly process is simple, which is conducive to the integrated deployment of mobile platforms or integrated optical modules.

[0054] In the aforementioned embodiments, unlike traditional solutions that rely on the stacking of multiple optical elements, these embodiments implement multiple core functions, including transmission adjustment, focus control, wavefront shaping, and beam reconstruction, within a single module (i.e., the modulation element). This significantly simplifies system construction and optical path configuration, lowering the assembly and adjustment threshold and reducing system complexity. Thanks to the passive solid-state structure of the modulation element, the overall system is unaffected by thermal drift, electrical noise disturbances, or material aging, making it particularly suitable for high-power, high-repetition-rate, or long-term stable operation scenarios. For example, it is suitable for system integration platforms with size constraints or high response speed requirements in fields such as high-precision laser processing, space optical communication, ultrafast laser modulation, adaptive imaging, wavefront correction, laser scanning, beam shaping, laser interferometry, and time-of-flight imaging. In these scenarios, due to the completely physical drive, passive element modulation, and rich spatial control dimensions in the main beam modulation process, it exhibits higher stability, reliability, and system compatibility.

[0055] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A laser holographic machining apparatus characterized by comprising: The laser holographic processing device comprises: a spatial light modulator arranged in a laser light path, the spatial light modulator being used for modulating a laser beam to form a first modulated light beam; a modulation element arranged in a propagation path of the first modulated light beam, the modulation element comprising a substrate and a tapered hole arranged on the substrate, a radius of the tapered hole being in a first-order curve, a second-order curve or a high-order nonlinear curve relationship with a depth; wherein a main modulation process is performed by the modulation element as a passive optical device, and the spatial light modulator only needs to provide the first modulated light beam with excellent spatial quality and flat wavefront for the modulation element; a multi-degree-of-freedom carrying platform, the multi-degree-of-freedom carrying platform being used for carrying the modulation element and driving the modulation element to translate and / or rotate in multiple directions; so that different positions of an inner wall of the tapered hole receive the first modulated light beam, and continuous and controllable multi-dimensional modulation of optical properties of an incident light beam in intensity, focal point position, wavefront topography and propagation direction is realized; The laser holographic processing device further comprises: a central control unit, the central control unit being in communication connection with the multi-degree-of-freedom carrying platform, the central control unit being used for sending a driving signal to the multi-degree-of-freedom carrying platform to realize translation and / or rotation of the multi-degree-of-freedom platform in multiple directions, and realize modulation of multiple light spot parameters by the tapered hole.

2. The laser holographic machining apparatus according to claim 1, wherein The substrate is prepared from fused quartz, sapphire, ceramic, silicon or high-reflectivity metal material.

3. The laser holographic machining apparatus according to claim 1, wherein The modulation element has a single tapered hole, or the modulation element has multiple tapered holes arranged in an array.

4. The laser holographic machining apparatus of claim 1, wherein The multi-degree-of-freedom carrying platform has translation and rotation degrees of freedom in three mutually perpendicular directions.

5. The laser holographic machining apparatus of claim 1, wherein The laser holographic processing device further comprises: a holographic lens arranged in an optical path of the first modulated light beam, the holographic lens being used for collimating the first modulated light beam, so that the collimated first modulated light beam is incident on the modulation element.

6. The laser holographic machining apparatus of claim 1, wherein The central control unit comprises: a controller, the controller being used for receiving user requirements and loading corresponding optical modulation target parameters according to the user requirements; an algorithm module, the algorithm module being in communication connection with the controller, the algorithm module being used for analyzing the optical modulation target parameters and generating a displacement trajectory planning command; a motion control card, the motion control card being in communication connection with the algorithm module, the motion control card being used for receiving the displacement trajectory planning command and sending a driving signal to the multi-degree-of-freedom carrying platform according to the displacement trajectory planning command.

7. The laser holographic machining apparatus of claim 1, wherein The tapered hole is a through hole, so that the tapered hole transmits at least part of the laser beam to complete modulation of the laser beam; or the tapered hole diffracts the laser beam to complete modulation of the laser beam.

8. The laser holographic machining apparatus of claim 1, wherein The tapered hole is a blind hole, so that the tapered hole receives the laser beam from an opening end, reflects the laser beam by a side wall of the tapered hole and emits the laser beam from the opening end of the tapered hole to complete modulation of the laser beam.

9. The laser holographic machining apparatus of claim 1, wherein The tapered hole is a tapered hole formed by femtosecond laser etching, diamond turning or molding technology.

Images