CN106695114B - Optical path structure of a laser engraving machine - Google Patents

Abstract

The invention relates to a light path structure of a laser engraving machine, belonging to the technical field of laser engraving; the optical path structure is sequentially provided with an objective lens, a pinhole, a diaphragm and an ellipsoidal reflector along the light propagation direction; the focal position of the objective lens is superposed with the far focal position of the ellipsoidal reflector, and a pinhole is arranged at the superposed position; the parallel light beams irradiate the objective lens along the direction of the optical axis to form a point light source at the position of the pinhole, and the point light source is reflected to a near-focus position by an ellipsoidal reflector and converged into a point light spot; the diaphragm can move between the pinhole and the ellipsoidal reflector along the direction of the optical axis, and the opening size of the diaphragm can be adjusted; the light path structure of the laser engraving machine can not only eliminate aberration in principle and improve the quality of laser beams, but also has the functions of accurately controlling the energy of the laser beams and changing the convergence angle of the laser beams.

Description

Optical path structure of a laser engraving machine

technical field

The invention relates to an optical path structure of a laser engraving machine, which belongs to the technical field of laser engraving.

Background technique

Laser engraving has a wide range of applications in woodcuts, stone carvings, seals and other fields. High-quality laser engraving requires strict control of the quality of the laser beam to eliminate the interference of aberrations to the greatest extent; at the same time, it is also necessary to precisely control the energy of the laser beam, the convergence angle and other parameters.

Contents of the invention

Aiming at the technical requirements of laser beam quality and adjustable parameters in the field of laser engraving, the invention discloses a laser engraving machine optical path structure, which can not only eliminate aberrations in principle, improve the quality of laser beams, but also have the ability to precisely control the laser beam Yes, the effect of changing the laser beam convergence angle.

The purpose of the present invention is achieved like this:

An optical path structure of a laser engraving machine, in which an objective lens, a pinhole, a diaphragm, and an ellipsoidal reflector are sequentially arranged along the direction of light propagation; the focal position of the objective lens coincides with the far focus position of the ellipsoidal reflector, and a pinhole is arranged at the overlap; parallel light beams The objective lens is irradiated along the optical axis, and a point light source is formed at the pinhole position, and then reflected by the ellipsoidal reflector to the near-focus position to converge into a spot; the diaphragm can move along the optical axis between the pinhole and the ellipsoidal reflector, The opening size of the diaphragm can be adjusted.

The optical path structure of the above-mentioned laser engraving machine, the opening size of the diaphragm can be adjusted, which is realized by the following structure:

The aperture is composed of a coaxially arranged window-transmissive disk that does not rotate around the axis, a radially notched rotary disk that rotates around the axis, and a circumferentially notched rotary disk that rotates around the axis;

The window is transparent to the first ring and the second ring of the disc in the circumferential direction, and the light is transparent in the area surrounded by the first radius and the second radius in the radial direction, and other areas are opaque; between the first radius and the second radius The central angle between them is α, and α can be divisible by 360 degrees;

The radial notch turntable is divided into 360/α areas in the circumferential direction, and in each area, the first ring and the second ring in the circumferential direction transmit light in the area surrounded by two radii in the radial direction , the other areas are opaque; the central angle between the two radii is arranged in an arithmetic sequence within 360/α areas, and the maximum does not exceed α;

The notched turntable in the circumferential direction is divided into 360/α areas in the circumferential direction, and in each area, there are two rings in the middle of the first ring and the second ring in the circumferential direction, and the first radius and the second ring in the radial direction The area surrounded by the two radii is transparent, and other areas are opaque; the distance between the two rings is arranged in an arithmetic sequence in 360/α areas, and the maximum distance between the first ring and the second ring .

The optical path structure of the above laser engraving machine is provided with an annular groove on the opposite side of the window transparent disc and the notched turntable in the circumferential direction and on both sides of the notched turntable in the radial direction, and balls are equally spaced in the annular groove, and the balls are fixed by the ball frame. ; The window transparent disc and the circumferential notch turntable are made of magnetic materials, and the magnetic poles of different names are placed opposite to each other, and the window transparent disc, the radial direction notch turntable and the circumferential notch turntable are adsorbed by magnetic force.

The optical path structure of the above laser engraving machine, the window transparent disc is fixedly installed on the sleeve, and the sleeve has two completely identical and parallel through grooves, and the through grooves cover the circumference of the 360-α angle; the radial direction notched turntable and A wrench is provided on the side of the notched turntable in the circumferential direction, and the wrench protrudes from the through groove provided on the sleeve, and the wrench is pulled to realize the rotation of the notched turntable in the radial direction and the notched turntable in the circumferential direction.

360/α wide grooves are arranged at equal intervals on the through groove, through holes pointing to both sides of the wide groove are arranged on the wrench, a spring is arranged in the through hole, and screw caps are installed on both sides of the spring; In the natural state of the spring, the distance between the two caps is greater than the width of the through groove, and in the compressed state of the spring, the distance between the two caps is smaller than the width of the through groove.

Beneficial effect:

First, in the optical path structure of the laser engraving machine of the present invention, since only the objective lens, pinhole, diaphragm and ellipsoid reflector are provided, in addition, a complete optical path system can be formed by adding a light source and an attenuation sheet, Less components, simple structure;

Second, in the optical path structure of the laser engraving machine of the present invention, since the lens structure in the traditional optical path is abandoned, an ellipsoidal reflector is used, which solves the aberration problem that the lens cannot overcome in principle, and greatly improves the quality of the laser beam , to effectively avoid the damage of the aberration beam to the outside of the engraving area, thereby improving the engraving quality;

Third, since the diaphragm can move along the optical axis between the pinhole and the ellipsoid mirror, the irradiation angle of the laser beam can be changed; at the same time, since the opening size of the diaphragm can be adjusted, the convergence of the laser beam can be changed horn;

Fourth, since the optical path structure of the laser engraving machine of the present invention adopts an ellipsoidal reflector, the bifocal conjugate property of the ellipsoidal reflector is used, that is, the light beam incident from the far focus can also be emitted from the far focus, the same as the lens structure or Compared with flat reflectors or spherical reflectors, it achieves large-angle convergence, which can not only improve the engraving time of coarse textures, but also achieve special engraving effects.

Description of drawings

Fig. 1 is a schematic diagram of the optical path structure of the laser engraving machine of the present invention.

FIG. 2 is a schematic structural diagram of a window transparent disk 31 .

FIG. 3 is a schematic structural view of the radially notched turntable 32 .

FIG. 4 is a schematic diagram of the structure of the notched turntable 33 in the circumferential direction.

Fig. 5 is a schematic diagram of the assembly structure of the window transparent disc, the notched rotary disc in the radial direction and the notched rotary disc in the circumferential direction.

Fig. 6 is a schematic structural view of the ball cage.

Fig. 7 is a schematic diagram of the installation structure between the diaphragm and the sleeve.

Fig. 8 is a partial view of the expanded slot.

Fig. 9 is a schematic diagram of the structural change when the wrench passes through the slot.

In the figure: 1 objective lens, 2 pinholes, 3 aperture, 31 window transparent disk, 32 notched turntable in radial direction, 33 notched turntable in circumferential direction, 34 ball, 35 ball holder, 36 wrench, 37 spring, 38 cap, 4 ellipsoid Reflector, 5 sleeves.

specific embodiment

The specific embodiments of the present invention will be described in further detail below in conjunction with the accompanying drawings.

Specific embodiment one

The schematic diagram of the optical path structure of the laser engraving machine in this embodiment is shown in FIG. 1 . The optical path structure of the laser engraving machine is sequentially provided with an objective lens 1, a pinhole 2, a diaphragm 3 and an ellipsoidal reflector 4 along the light propagation direction; Hole 2; the parallel light beam irradiates the objective lens 1 along the optical axis, forms a point light source at the pinhole 2 position, and then reflects to the near-focus position through the ellipsoidal reflector 4, converging into a point spot; The mirrors 4 move along the direction of the optical axis, and the opening size of the diaphragm 3 can be adjusted.

It should be noted that the diaphragm 3 can move along the optical axis between the pinhole 2 and the ellipsoid mirror 4, and those skilled in the art can realize it by referring to the structure in which the mirror lens moves axially relative to the housing in the zoom lens. No detailed description is required in this application.

Specific embodiment two

The optical path structure of the laser engraving machine in this embodiment, on the basis of the specific embodiment 1, further defines that the opening size of the diaphragm 3 can be adjusted, which is realized by the following structure:

The aperture 3 is composed of a coaxially arranged window transparent disk 31 that does not rotate around the axis, a radially notched turntable 32 that rotates around the axis, and a circumferentially notched turntable 33 that rotates around the axis;

The first ring and the second ring of the window transparent disk 31 in the circumferential direction are transparent in the area surrounded by the first radius and the second radius in the radial direction, and other areas are opaque; the first radius and the second radius The central angle between them is α, and α can be divisible by 360 degrees; the window transparent disk 31 is shown in Figure 2;

The radial notch turntable 32 is divided into 360/α areas in the circumferential direction, and in each area, the first ring and the second ring in the circumferential direction are transparent in the area surrounded by two radii in the radial direction. light, and other areas are opaque; the central angles between the two radii are arranged in an arithmetic sequence within the 360/α area, and the maximum does not exceed α; the radius direction notched turntable 32 is shown in Figure 3; what needs to be explained is , in the present invention, being arranged in an arithmetic sequence means that the numbers are arranged in an arithmetic sequence according to the order of size, but they may not be arranged in order;

The notched turntable 33 in the circumferential direction is divided into 360/α areas in the circumferential direction, in each area, two rings in the middle of the first ring and the second ring in the circumferential direction, the first radius and the second ring in the radial direction The area surrounded by the second radius is light-transmitting, and other areas are opaque; the distance between the two rings is arranged in an arithmetic sequence in 360/α areas, and the maximum does not exceed the distance between the first ring and the second ring Distance; the notch in the circumferential direction of the turntable 33 is shown in FIG. 4 .

In this embodiment, by rotating the notch turntable 32 in the radial direction and the notch turntable 33 in the circumferential direction, the light-transmitting area of the window transmissive disc 31 is arranged and combined with the light-transmitting area of the notch turntable 32 in the radial direction and the notch turntable 33 in the circumferential direction, and the aperture of the aperture is changed. The size of the opening changes the convergence angle of the laser beam.

Specific embodiment three

The optical path structure of the laser engraving machine in this embodiment, on the basis of the specific embodiment 1 or the specific embodiment 2, further defines the assembly structure of the window transparent disc 31 in the diaphragm 3, the radial direction notch rotary disc 32 and the circumferential direction notch rotary disc 33, As shown in Figure 5.

On the opposite side of the window transparent disk 31 and the notch turntable 33 in the circumferential direction and both sides of the notch turntable 32 in the radial direction, annular grooves are arranged, and balls 34 are distributed at equal intervals in the annular groove, and the balls 34 are fixed by the ball frame 35; The window transparent disk 31 and the circumferential notch rotary disk 33 are made of magnetic materials, and the magnetic poles of different names are oppositely placed, and the window transparent disk 31, the radial direction notch rotary disk 32 and the circumferential notch rotary disk 33 are adsorbed by magnetic force.

In this embodiment, the schematic structural view of the ball cage 35 is shown in Figure 6, the ball 34 is put into the hole of the ball cage 35, and in the direction perpendicular to the optical axis, the position of the ball 34 is limited by the ball cage 35; it should be noted that , The ball frame 35 needs to be made of a transparent material to ensure light transmission.

Specific embodiment four

The optical path structure of the laser engraving machine in this embodiment further defines the installation structure between the diaphragm 3 and the sleeve 5 on the basis of the specific embodiment 1, the specific embodiment 2 or the specific embodiment 3, as shown in FIG. 7 .

The window transparent disc 31 is fixedly installed on the sleeve 5, and the sleeve 5 has two completely identical through-slots arranged in parallel, and the through-slots cover the circumference at an angle of 360-α; A wrench 36 is provided on the side of the turntable 33 , and the wrench 36 protrudes from the through groove provided on the sleeve 5 , and the wrench 36 is pulled to realize the rotation of the notched turntable 32 in the radial direction and the notched turntable 33 in the circumferential direction.

The installation structure between the aperture 3 and the sleeve 5 in this embodiment can achieve the technical purpose of the radially notched turntable 32 and the circumferential notch turntable 33 rotating around their axes.

Specific embodiment five

The optical path structure of the laser engraving machine in this embodiment further defines the matching relationship between the wrench 36 and the through slot on the basis of the fourth embodiment.

Among them, 360/α wide grooves are arranged at equal intervals on the through groove, and the partial view of the through groove is shown in Figure 8;

The wrench 36 is provided with through holes pointing to both sides of the wide groove, and a spring 37 is arranged in the through hole, and screw caps 38 are installed on both sides of the spring 37; The distance between the two caps 38 is greater than the width of the through groove, and the distance between the two caps 38 is smaller than the width of the through groove when the spring 37 is in a compressed state.

The structural change of the wrench 36 when it passes through the slot is shown in FIG. 9 . It should be noted that the installation method between the spring 37 and the screw cap 38 can be realized by those skilled in the art, and no more detailed introduction is needed.

Such structural design can make the spanner 36 pass through the wide groove, under the elastic force of the spring 37, the two caps 38 are stuck in the wide groove, so as to realize the positioning of the notch rotary disk 32 in the radial direction and the notch rotary disk 33 in the circumferential direction. Furthermore, the window transparent disk 31 , the rotary disk 32 with notches in the radial direction and the rotary disk 33 with notches in the circumferential direction are arranged and combined at fixed positions.

Claims (2)

1. a laser engraving machine optical path structure is characterized in that, objective lens (1), pinhole (2), aperture (3) and ellipsoid reflector (4) are arranged successively along light propagation direction; Described objective lens (1) ) focus position coincides with the far focus position of the ellipsoid reflector (4), and a pinhole (2) is set at the coincidence place; the parallel light beam irradiates the objective lens (1) along the optical axis, forms a point light source at the position of the pinhole (2), and then passes through The ellipsoidal reflector (4) is reflected to the position near the focal point and converges into a point spot; the diaphragm (3) can move along the optical axis between the pinhole (2) and the ellipsoidal reflector (4), and the diaphragm (3) The opening size can be adjusted. 2. laser engraving machine optical path structure according to claim 1, is characterized in that, the opening size of diaphragm (3) can be adjusted, realizes by following structure: The aperture (3) is composed of a coaxially arranged window transparent disk (31) that does not rotate around the axis, a radially notched rotary disk (32) that rotates around the axis, and a circumferentially notched rotary disk (33) that rotates around the axis; The first ring and the second ring of the window transparent disk (31) in the circumferential direction are transparent in the area surrounded by the first radius and the second radius in the radial direction, and other areas are opaque; the first radius and the second radius The central angle between the two radii is α, and α can be divisible by 360 degrees; The radial notch turntable (32) is divided into 360/α areas in the circumferential direction, in each area, the first ring and the second ring in the circumferential direction, the area surrounded by two radii in the radial direction The inner light is transparent, and the other areas are opaque; the central angle between the two radii is arranged in an arithmetic sequence in the area of 360/α, and the maximum does not exceed α; The circumferential notch turntable (33) is divided into 360/α areas in the circumferential direction, in each area, two rings in the middle of the first ring and the second ring in the circumferential direction, and the first ring in the radial direction The area surrounded by the radius and the second radius is light-transmitting, and other areas are opaque; the distance between the two rings is arranged in an arithmetic sequence in 360/α areas, and the maximum does not exceed the distance between the first ring and the second ring. distance between.