A dual-beam coupled pulsed light-curing additive manufacturing method and device

Abstract

The present invention relates to the field of photocuring additive manufacturing, and more specifically to a dual-beam coupled pulsed photocuring additive manufacturing method and device. The method comprises the following steps: step S1: a violet laser beam emitted by a violet laser sequentially passes through a violet DMD chip and a long-wavelength dichroic mirror to enter a focusing objective lens, and is patterned and projected onto a photosensitive resin through the focusing objective lens to form an initial cured area of ​​any cross-section; step S2: a red laser beam emitted by a red laser sequentially passes through a red DMD chip and a short-wavelength dichroic mirror to enter a focusing objective lens, and is patterned and projected onto the boundary of the initial cured area through the focusing objective lens to achieve boundary shaping; step S3: a violet laser beam and a red laser beam are coupled in a dual-beam manner to construct a complex three-dimensional micro-nano structure layer by layer; the method can effectively solve the shortcomings of existing single-beam curing technology, such as inaccurate boundary morphology and high residual stress.

Description

Technical Field

[0001] The present invention relates to the field of photocuring additive manufacturing, and more particularly to a dual-beam coupled pulse photocuring additive manufacturing method and device. Background Art

[0002] Surface projection photocuring technology uses a digital micromirror device (DMD) as a dynamic mask and achieves layer-by-layer curing of photosensitive resins through patterned ultraviolet light irradiation, and is widely used in the preparation of high-resolution micro-nano structures. However, due to the Gaussian distribution of the projection spot, the light intensity in the central area is significantly higher than that at the edge, and the free radicals inside the resin diffuse and accumulate under long-term exposure, resulting in inaccurate cross-sectional boundary morphology and significant residual stress. Existing improvement measures mainly focus on adjusting the exposure dose, optimizing the optical path and the galvanometer scanning strategy, but lack a selective dissipation mechanism for excess free radicals at the boundary, making it difficult to simultaneously take into account the boundary shaping accuracy and mechanical properties of the formed part at the micro-nano scale. Therefore, it is urgent to introduce a forming method that can achieve efficient free radical suppression through an additional light beam after ultraviolet light curing, and combine real-time multi-field feedback with layered closed-loop control to meet the requirements of high flatness, high resolution and low residual stress preparation of complex three-dimensional micro-nano structures. Summary of the Invention

[0003] The purpose of the present invention is to provide a dual-beam coupled pulsed light-curing additive manufacturing method and device, which can effectively solve the shortcomings of existing single-beam curing technology such as inaccurate boundary morphology and high residual stress.

[0004] The purpose of the present invention is achieved through the following technical solutions:

[0005] A dual-beam coupled pulsed light-curing additive manufacturing method, the method comprising the following steps:

[0006] Step S1: The violet laser beam emitted by the violet laser passes through the violet DMD chip and the long-wavelength dichroic mirror in sequence and enters the focusing lens. The focusing lens then projects the violet laser beam onto the photosensitive resin in a patterned manner to form an initial solidification area of ​​any cross section.

[0007] Step S2: The red laser beam emitted by the red laser passes through the red DMD chip and the short-wavelength dichroic mirror in sequence and enters the focusing lens. The focusing lens then projects the red laser beam onto the boundary of the initial solidification area in a patterned manner to achieve boundary shaping.

[0008] Step S3: The violet laser beam and the red laser beam are coupled in a dual-beam manner to construct a complex three-dimensional micro-nanostructure layer by layer;

[0009] In step S3, the violet laser beam and the red laser beam are simultaneously projected for photocuring. The scanning periods and phase offsets of the galvanometers corresponding to the violet DMD chip and the red DMD chip complement each other to eliminate overlapping scanning blind spots. On the same projection plane, the violet light-cured pattern formed by the violet DMD chip in step S1 and the red light-shaped pattern formed by the red DMD chip in step S2 are superimposed and projected to simultaneously complete cross-section curing and boundary shaping. The displacement system drives the printing substrate to continuously move in the vertical Z-axis direction at a preset layer thickness Δz, thereby constructing a complex three-dimensional micro-nano structure layer by layer.

[0010] The method further includes the following steps: Step S4: using the curing pattern information collected by the feedback system, adjusting the angles and positions of the violet DMD chip, the red DMD chip, the aberration-correcting lens I, the aberration-correcting lens II, the long-wavelength dichroic mirror, and the short-wavelength dichroic mirror in real time, comparing the clarity of the projected pattern using a variance method, and adjusting the position of the focusing objective lens so that it is accurately focused on the printing substrate; and adjusting the power of the violet laser and the red laser in real time according to the curing pattern information;

[0011] The wavelength of the violet laser beam is 385±5nm, the wavelength of the red laser beam is 660±5nm, the half-width (FWHM) of the spectrum of the violet laser and the red laser is ≤20nm, the pulse duration of the violet laser beam is 550±5ms, the pulse duration of the red laser beam is 230±5ms, the pulse repetition frequency is 10-100Hz, and the duty cycle is 10%-90%;

[0012] The photosensitive resin is a composite light-curing material system containing epoxy compounds and thiol, and the concentration of the photoinitiator is 0.1 to 5 wt%;

[0013] The violet laser is a 385±5nm high-power semiconductor laser with an output power of ≥4W and a pulse width of ≤200fs; the red laser is a high-power pulse laser with a peak power of ≥1W, a pulse width of 2-30ms, and a repetition frequency of 10-100Hz;

[0014] The feedback system includes a CMOS sensor and a monitoring unit. Based on the principle of optical path reversibility, the feedback system transmits curing pattern information through a focusing objective lens in the optical path of the violet laser beam, collects the curing pattern information through the CMOS sensor and the monitoring unit, and synchronously captures the printing process image with a spatial resolution of ≤1μm and a real-time feedback frequency of ≥100Hz, and provides real-time feedback of the forming morphology information.

[0015] A dual-beam coupled pulsed light-curing additive manufacturing device includes an optical breadboard on which a violet laser and a red laser are mounted. The violet laser emits a violet laser beam that passes through a reflector I, a violet DMD chip, an aberration-correcting lens I, and a long-wavelength dichroic mirror in sequence, and finally irradiates the resin pool through a focusing objective lens. The red laser emits a red laser beam that passes through a reflector II, a red DMD chip, an aberration-correcting lens II, and a short-wavelength dichroic mirror in sequence, and the red laser beam passes through a focusing objective lens and irradiates the resin pool simultaneously with the violet laser beam. The resin pool is mounted on a focusing objective lens. Above the objective lens, a photosensitive resin is provided in a resin pool, a printing substrate is provided on the resin pool, a support base is installed on the optical breadboard, a displacement system is installed on the support base, the displacement system is a vertical displacement stage, the printing substrate is fixedly connected to the vertical displacement end of the displacement system, reflector I, purple light DMD chip, aberration-correcting lens I, long-wavelength pass dichroic mirror, focusing objective lens, reflector II, red light DMD chip, aberration-correcting lens II and short-wavelength pass dichroic mirror are respectively fixedly connected to multiple optical rods, and the multiple optical rods are respectively fixedly mounted on the optical breadboard through multiple optical rod brackets;

[0016] The feedback system is also provided in the loop of the violet laser beam. The feedback system includes a CMOS sensor and a monitoring unit. Based on the principle of optical path reversibility, the feedback system transmits curing pattern information through a focusing objective lens in the optical path of the violet laser beam. The feedback system is fixed to the optical breadboard via an optical rod and an optical rod bracket.

[0017] The angles and positions of the purple DMD chip, red DMD chip, aberration-correcting lens I, aberration-correcting lens II, long-wavelength pass dichroic mirror and short-wavelength pass dichroic mirror can be adjusted in real time according to the solidification pattern information collected by the feedback system.

[0018] The beneficial effects of the present invention are:

[0019] By combining red and violet light pulse beam coupling technology with real-time feedback detection of molding patterns, thickness and precise layer-by-layer movement on the Z-axis, submicron-level shaping of cross-sectional boundaries is effectively achieved, significantly improving the resolution and flatness of micro-nano structures. Ultraviolet light high-energy pulse exposure increases the rate of free radical generation, rapidly stimulates chain growth, and improves printing efficiency. The red light inhibition function accurately dissipates excess free radicals, inhibits irregular growth of boundaries during the curing process, improves the accuracy of the printing process, and significantly reduces thermal residual stress, fundamentally solving the problems of boundary roughness and stress concentration that are difficult to avoid in traditional photocuring additive manufacturing. Through a gradient cross-linking curing strategy, high-energy short pulses are used to achieve deep curing in the internal area, and low-energy long exposure mode is used in the boundary area, so that the molecular chains are rearranged in order and the generation of microcracks in the boundary area is eliminated. This method has good adaptability to different photosensitive resin systems while ensuring submicron high-precision forming, providing strong technical support for high-precision micro-nano additive manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0021] Figure 1 Schematic diagram of the structure of the dual-beam coupled pulsed light-curing additive manufacturing device of the present invention;

[0022] Figure 2 This is a schematic diagram of the process of violet light curing-red light boundary modification under dual-beam coupling conditions of the present invention;

[0023] Figure 3 It is a schematic diagram of the dual-beam coupling forming area of ​​the present invention.

[0024] In the figure: short-wavelength pass dichroic mirror 11; violet DMD chip 12; long-wavelength pass dichroic mirror 13; violet laser beam 14; violet laser 15; focusing objective lens 16; red DMD chip 17; red laser beam 18; red laser 19; photosensitive resin 21; resin pool 22; formed part 23; printing substrate 24; displacement system 31; support base 32; feedback system 41; optical connecting rod 51; optical connecting rod bracket 52; optical breadboard 53; reflector I 54; reflector II 55; aberration-correcting lens I 56; aberration-correcting lens II 57; violet light slicing pattern 61; red light slicing pattern 62; violet light curing pattern 63; red light shaping pattern 64; forming pattern 65. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below with reference to the accompanying drawings.

[0026] To effectively address the shortcomings of existing single-beam curing technology, such as inaccurate boundary morphology and high residual stress, a dual-beam coupled pulsed light-curing additive manufacturing method is described below in detail.

[0027] A dual-beam coupled pulsed light-curing additive manufacturing method, the method comprising the following steps:

[0028] Step S1: A violet laser beam 14 emitted by a violet laser 15 passes through a violet DMD chip 12 and a long-wavelength dichroic mirror 13 in sequence and enters a focusing objective lens 16. The violet laser beam 14 is then patterned and projected onto a photosensitive resin 21 by the focusing objective lens 16. The photosensitive resin 21 is a composite photocurable material system containing an epoxy compound and a thiol, and the concentration of the photoinitiator is 0.1 to 5 wt %. The photoinitiator molecules are excited by violet light and transition from a singlet state to a triplet state, thereby initiating free radical polymerization to form an initial cured region of any cross-section.

[0029] Step S2: The red laser beam 18 emitted by the red laser 19 passes through the red DMD chip 17 and the short-wavelength dichroic mirror 11 and is incident on the focusing lens 16. The focusing lens 16 then projects the red laser beam 18 onto the boundary of the curing area in a patterned manner. The triplet non-radiative dissipation mechanism is used to suppress the polymerization of free radicals at the boundary, thereby achieving submicron-level boundary modification.

[0030] Step S3: The violet laser beam 14 and the red laser beam 18 are coupled in a dual-beam manner to construct a complex three-dimensional micro-nanostructure layer by layer;

[0031] In step S3, the violet laser beam 14 and the red laser beam 18 are simultaneously projected and photocured. The scanning periods and phase offsets of the galvanometers corresponding to the violet DMD chip 12 and the red DMD chip 17 are complementary to eliminate overlapping scanning blind spots. On the same projection plane, the violet light-cured pattern formed by the violet DMD chip 12 in step S1 and the red light-shaped pattern formed by the red DMD chip 17 in step S2 are superimposed and projected to simultaneously complete cross-section curing and boundary shaping. The displacement system 31 drives the printing substrate 24 to continuously move along the vertical Z-axis direction at a preset layer thickness Δz, thereby constructing a complex three-dimensional micro-nano structure layer by layer.

[0032] Step S4: Using the projection pattern information collected by the feedback system 41, the angles and positions of the violet DMD chip 12, the red DMD chip 17, the aberration-correcting lens I 56, the aberration-correcting lens II 57, the long-wavelength pass dichroic mirror 13, and the short-wavelength pass dichroic mirror 11 are adjusted in real time. The clarity of the projection pattern is compared using the variance method, and the position of the focusing lens 16 is adjusted so that it is precisely focused on the printing substrate 24. The power of the violet laser 15 and the red laser 19 are adjusted in real time according to the curing pattern information to adapt them to the high-precision molding system, reduce beam diffusion, and obtain a molded part with high flatness and low residual stress.

[0033] The variance method evaluates pattern clarity through a three-stage process: first, image preprocessing is performed to convert the pattern into a grayscale image to preserve brightness information, and all pattern sizes are unified to eliminate resolution differences. Next, the statistical variance of the grayscale values ​​of all pixels in the entire pattern is calculated. This is the sum of the squares of the deviations of each pixel value from the average brightness divided by the total number of pixels. This variance value is directly used as a quantification indicator of clarity. Finally, based on the core principle of "high variance corresponds to high clarity"—that is, clear patterns have drastic changes in pixel values ​​due to rich details, while blurred patterns have low variance characteristics due to smooth transitions—the variance scores of multiple patterns are compared to achieve objective ranking. The larger the variance value, the higher the clarity.

[0034] The wavelength of the violet laser beam 14 is 385±5nm, the wavelength of the red laser beam 18 is 660±5nm, the spectral half-width (FWHM) of the violet laser 15 and the red laser 19 is ≤20nm, the pulse duration of the violet laser beam 14 is 550±5ms, the pulse duration of the red laser beam 18 is 230±5ms, the pulse repetition frequency is 10-100Hz, and the duty cycle is 10%-90%;

[0035] The violet laser 15 is a 385±5nm high-power semiconductor laser with an output power of ≥4W and a pulse width of ≤200fs; the red laser 19 is a high-power pulse laser with a peak power of ≥1W, a pulse width of 2 to 30ms, and a repetition frequency of 10 to 100Hz;

[0036] The feedback system 41 includes a CMOS sensor and a monitoring unit. Based on the principle of optical path reversibility, the feedback system 41 transmits curing pattern information through a focusing objective lens in the optical path of the violet laser beam 14, collects the curing pattern information through the CMOS sensor and the monitoring unit, and synchronously captures the printing process image with a spatial resolution of ≤1μm and a real-time feedback frequency of ≥100Hz, and provides real-time feedback of the forming morphology information.

[0037] The monitoring unit integrates a high-precision sensor module and a stacked CMOS imaging system. The high-precision sensor module, a confocal microscope, uses optical sectioning to provide 0.3μm defect detection. The stacked CMOS imaging system is a vertical three-dimensional integration of pixel layer, processing layer, and cache layer. It synchronously captures the printing process with a spatial resolution of ≤1μm and a real-time feedback frequency of ≥100Hz. Through the data fusion unit, the topography information is fed back in real time with a time synchronization accuracy of ±10μs.

[0038] like Figures 1 to 3As shown, the method uses a dual-beam coupled pulsed light-curing additive manufacturing device, which includes an optical breadboard 53, on which a violet laser 15 and a red laser 19 are mounted. The violet laser 15 emits a violet laser beam 14 which passes through a reflector I 54, a violet DMD chip 12, an aberration-correcting lens I 56 and a long-wavelength dichroic mirror 13 in sequence, and finally irradiates the resin pool 22 through a focusing objective lens 16. The red laser 19 emits a red laser beam 18 which passes through a reflector II 55, a red DMD chip 17, an aberration-correcting lens II 57 and a short-wavelength dichroic mirror 11 in sequence, and the red laser beam 18 passes through the focusing objective lens 16 and irradiates the resin pool 22 simultaneously with the violet laser beam 14. The resin pool 22 is mounted on a focusing objective lens. Above the focusing objective lens 16, a photosensitive resin 21 is provided in the resin pool 22, a printing substrate 24 is provided on the resin pool 22, a support base 32 is installed on the optical breadboard 53, a displacement system 31 is installed on the support base 32, and the displacement system 31 is a vertical displacement stage. The printing substrate 24 is fixedly connected to the vertical displacement end of the displacement system 31, and the reflector I 54, the purple DMD chip 12, the aberration-correcting lens I 56, the long-wavelength pass dichroic mirror 13, the focusing objective lens 16, the reflector II 55, the red DMD chip 17, the aberration-correcting lens II 57 and the short-wavelength pass dichroic mirror 11 are respectively fixedly connected to a plurality of optical rods 51, and the plurality of optical rods 51 are respectively fixedly mounted on the optical breadboard 53 via a plurality of optical rod brackets 52;

[0039] The system further includes a feedback system 41 disposed in the loop of the violet laser beam 14. The feedback system 41 includes a CMOS sensor and a monitoring unit. Based on the principle of optical path reversibility, the feedback system 41 transmits curing pattern information through a focusing objective lens in the optical path of the violet laser beam 14. The feedback system 41 is fixed to an optical breadboard 53 via an optical rod 51 and an optical rod bracket 52.

[0040] The angles and positions of the purple DMD chip 12, the red DMD chip 17, the aberration-correcting lens I 56, the aberration-correcting lens II 57, the long-wavelength pass dichroic mirror 13, and the short-wavelength pass dichroic mirror 11 can be adjusted in real time according to the curing pattern information collected by the feedback system 41;

[0041] Furthermore, the technical solution for controlling the angles of the purple DMD chip 12, the red DMD chip 17, the aberration-correcting lens I 56, the aberration-correcting lens II 57, the long-wave-pass dichroic mirror 13, and the short-wave-pass dichroic mirror 11 can use a servo motor or a stepper motor, etc., which are motors capable of angle control. The control method for controlling the positions of the purple DMD chip 12, the red DMD chip 17, the aberration-correcting lens I 56, the aberration-correcting lens II 57, the long-wave-pass dichroic mirror 13, and the short-wave-pass dichroic mirror 11 can adopt the mechanical drive method commonly used in the prior art. For example, an electric push rod is fixedly connected to an external bracket, a servo motor is fixedly connected to the telescopic end of the electric push rod, and the purple DMD chip 12, the red DMD chip 17, the aberration-correcting lens I 56, the aberration-correcting lens II 57, the long-wave-pass dichroic mirror 13 or the short-wave-pass dichroic mirror 11 are fixedly connected to the rotating end of the servo motor, thereby realizing the adjustment of the position or angle of the purple DMD chip 12, the red DMD chip 17, the aberration-correcting lens I 56, the aberration-correcting lens II 57, the long-wave-pass dichroic mirror 13 or the short-wave-pass dichroic mirror 11;

[0042] like Figure 1 As shown, the violet laser 15 emits a violet laser beam 14 which passes through the reflector I 54, the violet DMD chip 12, the aberration-correcting lens I 56 and the long-wavelength dichroic mirror 13 in sequence and enters the focusing objective 16, and is patterned and projected onto the photosensitive resin 21 through the focusing objective 16. The photosensitive resin 21 is a composite photocurable material system containing an epoxy compound and a thiol, and the concentration of the photoinitiator is 0.1 to 5 wt %, so that the photoinitiator molecules transition from a singlet state to a triplet state under the excitation of violet light and initiate free radical polymerization to form an initial cured area of ​​any cross section; the red laser 19 emits a red laser beam 18 which passes through the reflector II 55, the red DMD chip 17, the aberration-correcting lens II 57 and the short-wavelength dichroic mirror 11 in sequence and enters the focusing objective 16, and is patterned and projected onto the boundary of the cured area through the focusing objective 16, and the triplet non-radiative dissipation mechanism is used to suppress the boundary free radical polymerization, thereby achieving submicron boundary shaping;

[0043] like Figure 2 As shown, the controller generates a violet light slicing pattern 61 and a red light slicing pattern 62 according to the layer-by-layer slicing of the model to be printed. The violet laser beam 14 is projected through the violet DMD chip 12 to form a violet light curing pattern 63. Then, the red laser beam 18 is projected through the red DMD chip 17 to form a red light shaping pattern 64. The two are superimposed on the same projection plane to form a final formed pattern 65, thereby achieving high-precision violet light curing and sub-micron red light boundary shaping of the cross-sectional area.

[0044] like Figure 3As shown, the simultaneous cross-sectional shaping and boundary modification process of the present invention is demonstrated in the cross-sectional schematic diagram: First, a violet laser beam 14 is projected through a violet DMD chip 12 to form a violet curing pattern 63 corresponding to the desired cross-sectional profile. Simultaneously, a red laser beam 18 is projected through a red DMD chip 17 to form a red shaping pattern 64, quenching excess free radicals only at the boundaries of the curing area, achieving submicron-scale boundary shaping. During this process, the photosensitive resin 21 transforms from a liquid to a solid, forming a formed part 23 on a printed substrate 24. In this cross-sectional structure, the resin pool 22, printed substrate 24, and formed part 23 cooperate to ensure that after each curing and shaping cycle, the displacement system 31 drives the printed substrate 24 to maintain its position along the vertical Z-axis Δz, providing stable support for the next layer of formation, ultimately forming the desired complex three-dimensional micro-nanostructure.

Claims

1. A dual-beam coupled pulsed light-curing additive manufacturing device, characterized by: The device includes an optical breadboard (53), on which a violet laser (15) and a red laser (19) are mounted. The violet laser (15) emits a violet laser beam (14) which passes through a reflector I (54), a violet DMD chip (12), an aberration-eliminating lens I (56) and a long-wavelength dichroic mirror (13) in sequence, and finally irradiates the resin pool (22) through a focusing objective lens (16). The red laser (19) emits a red laser beam (18) which passes through a reflector II (55), a red DMD chip (17), an aberration-eliminating lens II (57) and a short-wavelength dichroic mirror (11) in sequence, and the red laser beam (18) passes through a focusing objective lens (16) and irradiates the resin pool (22) simultaneously with the violet laser beam (14). The resin pool (22) is mounted above the focusing objective lens (16). 2) is provided with a photosensitive resin (21), a printing base (24) is provided on the resin pool (22), a support base (32) is installed on the optical breadboard (53), a displacement system (31) is installed on the support base (32), the displacement system (31) is a vertical displacement stage, the printing base (24) is fixedly connected to the vertical displacement end of the displacement system (31), the reflector I (54), the purple DMD chip (12), the aberration-correcting lens I (56), the long-wave-pass dichroic mirror (13), the focusing objective lens (16), the reflector II (55), the red DMD chip (17), the aberration-correcting lens II (57) and the short-wave-pass dichroic mirror (11) are respectively fixedly connected to a plurality of optical connecting rods (51), and the plurality of optical connecting rods (51) are respectively fixedly installed on the optical breadboard (53) through a plurality of optical connecting rod brackets (52).

2. The dual-beam coupled pulsed light-curing additive manufacturing device according to claim 1, characterized in that: The invention also includes a feedback system (41) arranged in the loop of the violet laser beam (14), the feedback system (41) including a CMOS sensor and a monitoring unit. According to the principle of optical path reversibility, the feedback system (41) transmits curing pattern information through a focusing objective lens in the optical path of the violet laser beam (14), and the feedback system (41) is fixed on an optical breadboard (53) through an optical connecting rod (51) and an optical connecting rod bracket (52).

3. The dual-beam coupled pulsed light-curing additive manufacturing device according to claim 2, characterized in that: The angles and positions of the purple DMD chip (12), the red DMD chip (17), the aberration-correcting lens I (56), the aberration-correcting lens II (57), the long-wavelength dichroic mirror (13), and the short-wavelength dichroic mirror (11) can be adjusted in real time according to the solidification pattern information collected by the feedback system (41).

4. The method for additive manufacturing using a dual-beam coupled pulsed light-curing additive manufacturing device according to claim 2, characterized in that: The method comprises the following steps: Step S1: The violet laser beam (14) emitted by the violet laser (15) passes through the violet DMD chip (12) and the long-wavelength dichroic mirror (13) in sequence and is incident on the focusing lens (16), and is patterned and projected onto the photosensitive resin (21) through the focusing lens (16), forming an initial solidification area of ​​an arbitrary cross section; Step S2: The red laser beam (18) emitted by the red laser (19) passes through the red DMD chip (17) and the short-wavelength dichroic mirror (11) in sequence and is incident on the focusing lens (16), and is patterned and projected onto the boundary of the initial solidification area through the focusing lens (16) to achieve boundary modification; Step S3: The violet laser beam (14) and the red laser beam (18) are coupled in a dual-beam manner to construct a complex three-dimensional micro-nanostructure layer by layer.

5. The dual-beam coupled pulsed light-curing additive manufacturing method according to claim 4, characterized in that: In the step S3, the violet laser beam (14) and the red laser beam (18) are simultaneously projected for photocuring, and the scanning periods and phase shifts of the galvanometers corresponding to the violet DMD chip (12) and the red DMD chip (17) are complementary to eliminate the overlapping scanning blind spots. On the same projection plane, the violet curing pattern formed by the violet DMD chip (12) in step S1 and the red light shaping pattern formed by the red DMD chip (17) in step S2 are superimposed and projected to simultaneously complete cross-section curing and boundary shaping. The displacement system (31) drives the printing substrate (24) to continuously move in the vertical Z-axis direction with a preset layer thickness Δz to construct a complex three-dimensional micro-nano structure layer by layer.

6. The dual-beam coupled pulsed light-curing additive manufacturing method according to claim 4, characterized in that: The method further includes the following steps: Step S4: using the curing pattern information collected by the feedback system (41), adjusting the angles and positions of the violet DMD chip (12), the red DMD chip (17), the aberration-correcting lens I (56), the aberration-correcting lens II (57), the long-wave dichroic mirror (13), and the short-wave dichroic mirror (11) in real time, comparing the clarity of the projected pattern with the variance method, and adjusting the position of the focusing lens (16) so that it is accurately focused on the printing substrate (24); and adjusting the power of the violet laser (15) and the red laser (19) in real time according to the curing pattern information.

7. The dual-beam coupled pulsed light-curing additive manufacturing method according to claim 4, characterized in that: The wavelength of the violet laser beam (14) is 385±5 nm, the wavelength of the red laser beam (18) is 660±5 nm, the half-width at half maximum (FWHM) of the spectrum of the violet laser (15) and the red laser (19) is ≤20 nm, the pulse duration of the violet laser beam (14) is 550±5 ms, the pulse duration of the red laser beam (18) is 230±5 ms, the pulse repetition frequency is 10 to 100 Hz, and the duty cycle is 10% to 90%.

8. The dual-beam coupled pulsed light-curing additive manufacturing method according to claim 4, characterized in that: The photosensitive resin (21) is a composite photocurable material system containing an epoxy compound and a thiol, and the concentration of the photoinitiator is 0.1 to 5 wt%.

9. The dual-beam coupled pulsed light-curing additive manufacturing method according to claim 4, characterized in that: The violet laser (15) is a 385±5nm high-power semiconductor laser with an output power of ≥4W and a pulse width of ≤200fs; the red laser (19) is a high-power pulse laser with a peak power of ≥1W, a pulse width of 2 to 30ms, and a repetition frequency of 10 to 100Hz.

10. The dual-beam coupled pulsed light-curing additive manufacturing method according to claim 6, characterized in that: The feedback system (41) includes a CMOS sensor and a monitoring unit. According to the principle of optical path reversibility, the feedback system (41) transmits curing pattern information through a focusing objective lens in the optical path of the violet laser beam (14), collects the curing pattern information through the CMOS sensor and the monitoring unit, and synchronously captures the printing process image with a spatial resolution of ≤1μm and a real-time feedback frequency of ≥100Hz, and feeds back the forming morphology information in real time.

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