Zoom laser illuminator with elliptical spot

Abstract

The application discloses a zoom laser illuminator of an elliptical light spot, which comprises a rear fixed group, a compensation group, a zoom group and a front fixed group which are sequentially arranged along an optical axis from an optical fiber end face outward, the front fixed group is provided with a non-rotationally symmetrical mirror group, the non-rotationally symmetrical mirror group is provided with a cylindrical type double quadratic surface mirror, and the control of a light spot aspect ratio is realized. According to the application, a specific relationship is met at any zoom position, the illumination light spot is ensured to be an ellipse with a ratio of major axis to minor axis of 16:9, and the ratio of major axis to minor axis of the light spot is unchanged at any illumination angle. The illuminator realizes the change of focal length by moving the internal mirror group along the optical axis direction, and the image plane position is basically unchanged during the zooming process. The lens with the double quadratic surface type is used to realize the control of the meridian and sagittal direction focal length. The laser illuminator disclosed by the application can emit an elliptical light spot, has the zoom function, the ratio of major axis to minor axis of the light spot is unchanged during the change of the illumination angle, and can be matched with a zoom lens.

Description

TECHNICAL FIELD

[0001] The present application relates to a zoom laser illuminator of an elliptical light spot, belonging to the field of laser illumination. BACKGROUND

[0002] The laser illumination technology using laser for auxiliary light supplement has been widely applied in night vision security and other fields, and has the advantages of high brightness, long action distance, low cost and the like. The existing long-distance laser illuminator mostly uses a fiber output semiconductor laser as a light source, and is matched with a zoom laser emission lens. The zoom emission lens is mostly designed according to the principle of imaging, and can continuously change the emission angle of the light spot within a certain range. The laser illuminator of this type has the advantages of high uniformity of the outgoing light spot and clear edges.

[0003] The light spot of the existing laser illuminator is generally similar to the shape of the used optical fiber, that is, circular. In some application scenarios, the light spot needs to be elliptical with a long axis and a short axis. In addition, in the application of security and night vision, the laser illumination needs to be matched with a zoom security lens. At present, the aspect ratio of the target surface of a high-definition camera is generally 16:9, that is, the field of view of the security lens is a rectangle with an aspect ratio of 16:9. When the laser light spot is inscribed in the upper and lower field of view of the lens, the laser utilization rate is 100%, but the light supplement range is small, causing the waste of the field of view. When the light spot is inscribed in the left and right field of view, the laser utilization rate is 67.6%. If the laser light spot fills the full screen, the laser utilization rate is only 54.42%. Although these two cases make full use of the field of view of the camera, they cause the waste of laser energy. If the aspect ratio of the laser light spot can be changed to be the same as that of the target surface of the camera, the laser utilization rate can reach 100% under the premise of ensuring the illumination field of view, which greatly improves the efficiency of laser use, is conducive to reducing the laser power and energy consumption. The existing laser illuminator can emit an elliptical light spot, such as patent CN201410130325.1. However, the elliptical light spot of the existing laser illuminator is unstable during the change of the illumination angle, that is, it will deviate, and cannot be matched with the zoom lens. SUMMARY

[0004] In view of the defects of the prior art, the present application provides a zoom laser illuminator of an elliptical light spot. The laser illuminator can emit an elliptical light spot, has a zoom function, and the ratio of the long axis to the short axis of the light spot is unchanged during the change of the illumination angle, so that it can be matched with the zoom lens.

[0005] In order to solve the technical problem, the technical scheme adopted by the present application is: an elliptical light spot zooming laser illuminator, comprising a rear fixed group, a compensation group, a zooming group and a front fixed group arranged along an optical axis in sequence from the outside of the end face of an optical fiber, wherein the front fixed group is provided with a non-rotationally symmetric mirror group, and the non-rotationally symmetric mirror group is provided with a cylindrical type double quadratic surface mirror to realize the control of the length-width ratio of the light spot; in the present zooming laser, the first lens to the fifth lens of the front group are non-rotationally symmetric mirror groups, and the sixth lens of the front group to the lens of the rear group are rotationally symmetric mirror groups, and the present zooming laser illuminator satisfies the following relationship:

[0006]

[0007] Wherein, f′ s , f′ t are the sagittal and meridional focal lengths of the non-rotationally symmetric mirror group, f′ j is the equivalent focal length of the rotationally symmetric mirror group, d sj , d tj are the distances between the sagittal and meridional surfaces of the non-rotationally symmetric mirror group and the equivalent main surface of the rotationally symmetric mirror group, and the relationship is satisfied at any zooming position, which ensures that the illumination light spot is an ellipse with a length-to-short axis ratio of 16:9, and the length-to-short axis ratio of the light spot is unchanged at any illumination angle.

[0008] The illumination lens moves along the optical axis direction through the internal mirror group to realize the change of the focal length, and the image plane position is basically unchanged during the zooming process, that is, the conjugate distance is approximately equal, which can be equivalent to the relationship (1):

[0009]

[0010] Wherein, L′0 is the image distance when the system is in long focus, L0 is the object distance when the system is in long focus, Δ0 is the main surface distance when the system is in long focus, and the sum of the three is the initial conjugate distance of the system; L′ i is the image distance when the system is in any zooming position, L i is the object distance when the system is in any zooming position, Δ i is the main surface distance when the system is in any zooming position, and the sum of the three is the conjugate distance during the zooming process of the system; f′0 is the long focus focal length. The condition ensures the zooming function of the illuminator.

[0011] Further, the zoom laser illuminator uses double quadratic surface mirrors to control the focal length in the meridional and sagittal directions; the fiber core is circular, to achieve an elliptical output spot, the optical system of the laser illuminator needs to have different optical powers in the meridional and sagittal directions under the condition that the relative positions of the lenses are unchanged, only the optical power in the cross section of the optical axis of the optical system is considered, the cross section is taken as a reference surface, and the reference surface is rotated along the optical axis, during the rotation, the optical power of the optical system in the reference surface will change according to the rotation angle, therefore, the rotation process can be understood as another zoom process. The rotation angle is defined as the angle between the reference surface and the meridional plane, at the beginning of the rotation, the rotation angle is 0°, the reference surface coincides with the meridional plane of the optical system, at the end of the rotation, the rotation angle is 90°, the reference surface coincides with the sagittal plane of the system. During the rotation, the position of the image surface of the system still needs to remain basically unchanged, this function is realized by a non-rotationally symmetric mirror group; one or two double quadratic surface mirrors realize the zoom function, and the remaining double quadratic surface mirrors realize compensation of the image surface position. Since most of the components of the system are rotationally symmetric surfaces, their properties do not change when the angle is changed, therefore, only the mirror group containing non-rotationally symmetric surfaces is considered. Under different angles, the conjugate distance still needs to be approximately equal, that is, the relationship (2) is satisfied:

[0012]

[0013] Wherein, l′0 is the image distance of the meridional plane of the non-rotationally symmetric mirror group, l0 is the object distance of the meridional plane of the non-rotationally symmetric mirror group, δ0 is the equivalent principal surface distance of the non-rotationally symmetric mirror group, and the sum of the three is the conjugate distance of the meridional plane of the non-rotationally symmetric mirror group; l i ′ is the image distance after the non-rotationally symmetric mirror group is rotated by any angle, l i is the object distance when the non-rotationally symmetric mirror group is rotated by any angle, δ i is the equivalent principal surface distance when the non-rotationally symmetric mirror group is rotated by any angle, and the sum of the three is the conjugate distance under any angle of the non-rotationally symmetric mirror group; f′ t is the focal length of the meridional plane of the non-rotationally symmetric mirror group.

[0014] The relationship (1) and the relationship (2) together ensure that under any illumination angle, the illumination spot has high uniformity, and the edge is clear and sharp.

[0015] Further, the compensation group and the zoom group have the ability to move along the optical axis, by adjusting the relative positions of the zoom group and the compensation group, the focal length of the system is adjusted and the image surface position is compensated.

[0016] Further, during the process of changing the illumination angle of the laser illuminator from small to large, the compensation group moves gradually from away from the fiber end face to close to the fiber end face, and the zoom group moves from close to the fiber end face to away from the fiber end face.

[0017] Further, in the zooming process, the zoom group and the compensation group pass through the point with the imaging magnification of -1 at the same time.

[0018] Further, the front fixed group is composed of 7 lenses, and the front 5 lenses of the front fixed group form a non-rotationally symmetric mirror group, and in the meridian and sagittal directions, the image-side focal points of the front 3 lenses and the object-side focal points of the rear 2 lenses approximately coincide, and the laser divergence angle is amplified by different multiples in the meridian and sagittal directions.

[0019] Further, the third lens, the fourth lens and the fifth lens in the non-rotationally symmetric mirror group are all cylindrical type double quadratic surface mirrors.

[0020] Further, the present zooming laser illuminator satisfies: f' L / f' S >> 37, D / f' L > 0.5, f' L , f' S are the longest focus and the shortest focus focal length values of the system respectively, and D is the maximum light aperture.

[0021] Further, the fiber end face is a 400 mu m core diameter multimode fiber light emitting end face, and the fiber length is > 1 m.

[0022] The beneficial effects of the present application are:

[0023] 1. The spot is elliptical, the ratio of the major axis to the minor axis is the same as the aspect ratio of the monitoring lens, and the light energy utilization rate is high.

[0024] 2. It has zooming function, and the ratio of the major axis to the minor axis of the spot does not change during the change of the illumination angle, which can be matched with the zooming lens.

[0025] 3. It has zooming function, and the illumination angle can be adjusted in a large range.

[0026] 4. At any illumination angle, the spot maintains high uniformity, and the edge is clear and sharp.

[0027] 5. Using the imaging principle design, cooperating with the use of large core diameter multimode fiber, the spot uniformity is high and the edge is clear.

[0028] 6. The total length of the system is fixed, so that the laser illuminator is in a closed state, and the structural stability is high.

[0029] 7. The system has high transmittance and low cost. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is the spot illumination range of the present application compared with the circular spot;

[0031] Figure 2 The meridian plane schematic view of the optical system of the elliptical spot zoom laser illuminator of the present application;

[0032] Figure 3 The sagittal plane schematic view of the optical system of the elliptical spot zoom laser illuminator of the present application;

[0033] Figure 4 The diagram of the distance between the meridian plane zoom group and the compensation group and the distance from the fiber end face and the system focal length of the present application;

[0034] Figure 5 The long focal lens MTF diagram of the laser illuminator of the present application;

[0035] Figure 6 The intermediate focal lens MTF diagram of the laser illuminator of the present application;

[0036] Figure 7 The short focal lens MTF diagram of the laser illuminator of the present application;

[0037] In the figure: 1 is the first lens of the front group, 2 is the second lens of the front group, 3 is the third lens of the front group, 4 is the fourth lens of the front group, 5 is the fifth lens of the front group, 6 is the sixth lens of the front group, 7 is the seventh lens of the front group, 8 is the zoom group lens, 9 is the compensation group lens, 10 is the rear group lens, 11 is the fiber light emitting end face, A is the moving curve of the zoom group lens 8, B is the moving curve of the compensation group lens 9. DETAILED DESCRIPTION

[0038] The present application will be further described below in conjunction with specific embodiments.

[0039] Embodiment 1

[0040] The technical solutions in the embodiments of the present application will be described clearly and completely below. The embodiments described in the present application are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0041] The specific embodiments of the present application will be described in detail below in conjunction with the drawings.

[0042] As Figure 1As shown in the figure, the spot illumination range of the present application is compared with the common circular spot illumination range when the spot is tangent to the horizontal field of view of the camera. The rectangular frame is the field of view of the camera, the left side is the circular spot illumination range, and the shaded range is the actual laser utilization range. It can be seen that the circular spot has part of the laser energy exceeding the field of view range, causing waste of light energy, and this part of the area accounts for about 32.4% of the total area of the spot. The right side is the spot range of the present application. It can be seen that the elliptical spot is entirely located within the rectangular frame, and all the light energy is utilized.

[0043] The present embodiment discloses a zoom laser illuminator of an elliptical spot, as shown in the figure. Figure 2 、 Figure 3 As shown in the figure, the optical path schematic diagram of the meridian and sagittal section of the present embodiment is given. The zoom laser illuminator described in the present embodiment starts from the fiber emitting end surface 11 and then has, in order, a rear group, a compensation group, a variable magnification group, and a front group.

[0044] The fiber emitting end surface 11 is the end surface of a large-core multimode fiber, and the fiber length is greater than 1 m. The fiber has a homogenization effect, and the large-core fiber has a large number of modes. The mixing and superposition of the modes in the laser transmission process ensure that the laser at the fiber end surface has high uniformity and clear edges.

[0045] The rear group, the compensation group, and the variable magnification group are each composed of a lens. The rear group lens 10 is a thick crescent lens with positive focal power, which converges the light beam. The variable magnification group lens 8 and the compensation group lens 9 use double-concave and double-convex lenses, respectively. By adjusting the relative positions of the variable magnification group and the compensation group, the focal length of the system can be adjusted and the compensation of the image plane position can be achieved, so that the illumination angle of the laser illuminator can be adjusted in a large range while the image plane position remains unchanged, achieving good illumination effect in the entire zoom process. The front group is composed of seven lenses. The sixth lens 6 and the seventh lens 7 of the front group are a set of cemented lenses with positive focal power, which further converges the light beam. The first lens to the fifth lens of the front group in the present zoom laser are non-rotationally symmetric lens groups, and the sixth lens to the rear group lens are rotationally symmetric lens groups.

[0046] Except for the sixth lens 6 and the seventh lens 7 of the front group, the remaining lenses of the front group form a Galilean telescope structure (non-rotationally symmetric lens group). The first lens 1, the second lens 2, and the third lens 3 of the front group are the first part of the structure. The third lens 3 of the front group is a cylindrical type double quadratic surface lens, i.e., a cylindrical lens. The fourth lens 4 and the fifth lens 5 of the front group are the second part. Both lenses in this part are cylindrical type double quadratic surface lenses, i.e., cylindrical lenses. In the meridian and sagittal directions, the image side focal points of the first three lenses and the object side focal points of the last two lenses approximately coincide, and the laser divergence angle is magnified by different multiples in the meridian and sagittal directions.

[0047] The specific parameters of the lenses in a specific structure of the laser illuminator are shown in Table 1, wherein the side of the lens away from the end face of the optical fiber is the front surface, and the side close to the end face of the optical fiber is the rear surface:

[0048] Table 1

[0049] Surface type Radius of curvature Thickness Material refractive index Material Abbe number S1 Sphere 44.58 6 1.62 60.4 S2 Sphere 177.69 4.98 - - S3 Sphere -125.00 3 1.72 29.5 S4 Sphere 51.34 5 1.75 52.3 S5 Cylinder * 25.64 - - S6 Sphere INF 3 1.52 64.2 S7 Cylinder * 27.22 - - S8 Cylinder * 3 1.52 64.2 S9 Sphere -105.91 1 - - S10 Sphere 25.07 5 1.80 46.6 S11 Sphere -48.15 2 2 25.4 S12 Sphere 203.84 * - - S13 Sphere -10.13 2 1.9 31.3 S14 Sphere 7.88 * - - S15 Sphere 11.63 3 2 25.4 S16 Sphere -124.93 * - - S17 Sphere 2.77 3 2 25.4 S18 Sphere 3.14 - - -

[0050] The cylindrical radius is as follows:

[0051] Table 2

[0052]

[0053]

[0054] The interval thickness of the moving group at different focal lengths is as follows:

[0055] Table 3

[0056] Sphere 52 22 1.4 S13 27.39 26.89 8.75 S15 3.14 11.98 34.42 S17 14.63 6.29 2

[0057] As shown in Meridional focal length / mm , a diagram showing the relationship between the distance of the zoom group lens 8 and the compensation group lens 9 from the front surface of the rear group lens 10 and the focal length of the system is given. Figure 4 In the diagram, the vertical coordinate is the distance of the lens from the front surface of the rear group lens 10, and the horizontal coordinate is the focal length of the laser illuminator at this time; the A curve is the motion curve of the zoom group lens 8, and the B curve is the motion curve of the compensation group lens 9. It can be seen from Figure 4 that during the change of the focal length of the illuminator from small to large, the distance of the zoom group lens 8 from the front surface of the rear group lens 10 gradually increases, and the distance of the compensation group lens 9 from the front surface of the rear group lens 10 gradually decreases. There is no sudden change point in the smooth curve during zooming.

[0058] As shown in Figure 4 , Figure 5 , Figure 6 Figure 7 , the MTF diagrams at three focal lengths of the lens are shown. It can be seen that the lens has good image quality at each focal length segment. The light spot has the advantages of high uniformity and clear edges.

[0059] When the laser illuminator irradiates an infinite distance target, the conjugate distance is the distance from the rear surface of the rear group lens 10 to the image side focal plane, and the difference between the conjugate distances is the difference between the positions of the focal planes. The focal lengths of 52 mm, 22 mm and 1.4 mm are taken for calculation, and the rear surface of the rear group lens 10 is taken as the reference surface. The distances of the focal planes from the rear surface of the rear group lens 10 are 1.012242, 1.019222 and 1.012929 respectively, i.e. (L′0+L0+Δ0)-(L′ i +L i+Δ i The values ​​are 0.00698 and 0.000687 respectively, and f′0 = 52 mm, satisfying the condition.

[0060]

[0061] The laser illuminator has a non-rotationally symmetric lens group consisting of a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, and a fifth lens 5. Taking the infinity target as the object plane, the conjugate distance of this part is the distance from the infinity target to the image-side focal plane of this part of the lens group, and the difference in conjugate distances is the difference in focal plane position. Taking angles of 0° and 90°, i.e., the meridional plane and the sagittal plane, the distances from the focal plane to the rear surface of the fifth lens 5 are 851.610158 and 851.252008, respectively, i.e., (l′0+l0+δ0)-(l i ′+L i +δ i f' = 0.35815 t =1380.94mm, which satisfies the requirement.

[0062]

[0063] Formula (1) ensures that the image plane position remains basically unchanged during zooming, that is, the conjugate distance is approximately equal.

[0064] Together with formula (1), formula (2) ensures that the illumination spot has high uniformity and clear, sharp edges under any illumination angle.

[0065] For the laser illuminator, calculations were performed at three positions with focal lengths of 52mm, 22mm, and 1.4mm, yielding the following data.

[0066]

[0067]

[0068] satisfy

[0069]

[0070] Among them, f s ′、f t ′ represents the sagittal and meridional focal lengths of the non-rotationally symmetric mirror group, respectively, f j ′ is the equivalent focal length of the rotationally symmetric lens group, d sj d tj Let be the distance between the sagittal and meridional planes of the non-rotationally symmetric mirror group and the equivalent principal plane of the rotationally symmetric mirror group. This relationship should be satisfied at any zoom position, ensuring that the illumination spot is an ellipse with a major-to-minor axis ratio of 16:9, and that the major-to-minor axis ratio of the spot remains unchanged at any illumination angle.

[0071] The laser illuminator is to prevent mutual influence of lenses during zooming, and the moving lens group lens spacing is not less than 2mm, which reserves sufficient space for mechanical design and adjustment while keeping the structure compact.

[0072] The laser illuminator has a meridional plane long-focus end focal length f L ′ = 52mm, and a short-focus end focal length f s ′ = 1.4mm, and a zoom ratio f L / f′ S > 37, D is the maximum clear aperture, D / f′ L > 0.5, f′ L , f′ S are respectively the longest-focus and shortest-focus focal length values of the system, and D is the maximum clear aperture.

[0073] The zoom laser illuminator with an elliptical light spot has the following functions:

[0074] 1) The zoom function is provided, and the illumination angle can be adjusted in a large range;

[0075] 2) The light spot is elliptical, and the ratio of the major axis to the minor axis can be 16:9 considering the actual application environment;

[0076] 3) The ratio of the major axis to the minor axis in the light spot does not change at any illumination angle;

[0077] 4) The light spot maintains high uniformity at any illumination angle, and the edge is clear and sharp.

[0078] The above description is only the basic principle and preferred embodiment of the present application, and the improvements and replacements made by the person skilled in the art according to the present application belong to the protection scope of the present application.

Claims

1. A zoom laser illuminator of elliptical light spot, comprising a rear fixed group, a compensation group, a zoom group and a front fixed group which are arranged along the optical axis in sequence with the fiber end face outward, characterized in that: The front fixed group is composed of 7 lenses, the first lens to the fifth lens of the front fixed group are non-rotationally symmetric lens groups, the sixth lens of the front fixed group to the rear fixed group lens are rotationally symmetric lens groups, the third lens, the fourth lens and the fifth lens in the non-rotationally symmetric lens group are all cylindrical type double quadratic surface lenses; in the non-rotationally symmetric lens group, the image side focal points of the first three lenses and the object side focal points of the last two lenses approximately coincide in the meridional and sagittal directions, the laser divergence angle is amplified by different multiples in the meridional and sagittal directions respectively; the zoom laser illuminator satisfies the following relationship: ； wherein, , are the sagittal and meridional focal lengths of the non-rotationally symmetric lens group, respectively, is the effective focal length of the rotationally symmetric lens group, , is the distance between the principal planes of the sagittal and meridional planes of the non-rotationally symmetric lens group and the effective principal plane of the rotationally symmetric lens group, which relationship is satisfied at any zoom position, ensuring that the illumination spot is an ellipse with a ratio of major to minor axis of 16:9, and that the ratio of major to minor axis of the spot is invariant at any illumination angle.

2. A zoom laser illuminator of elliptical light spot according to claim 1, characterized in that: The zoom laser illuminator satisfies the relationship (1) during zooming: （1）， wherein, is the image distance of the system at long focus, is the object distance of the system at long focus, is the principal plane distance of the system at long focus, the sum of the three is the initial conjugate distance of the system; is the image distance of the system at any zoom position, is the object distance of the system at any zoom position, is the principal plane distance of the system at any zoom position, the sum of the three is the conjugate distance of the system during zooming; is the long focus distance; this relationship ensures that the image plane position of the zoom laser illuminator is basically unchanged during zooming, i.e. the conjugate distance is approximately equal.

3. A zoom laser illuminator of elliptical light spot according to claim 2, characterized in that: The zoom laser illuminator uses double quadratic surface lenses to control the focal length in the meridional and sagittal directions; the fiber core is circular, in order to realize the output spot as an ellipse, the optical system of the laser illuminator needs to have different optical powers in the meridional and sagittal directions under the condition that the relative positions of the lenses are unchanged, only the optical power in the cross section of the optical axis of the optical system is considered, the reference surface is rotated along the optical axis, during the rotation process, the optical power of the optical system in the reference surface changes according to the rotation angle, the rotation process is understood as another zooming process, the rotation angle is defined as the angle between the reference surface and the meridional plane, at the beginning of the rotation, the rotation angle is 0°, the reference surface coincides with the meridional plane of the optical system, at the end of the rotation, the rotation angle is 90°, the reference surface coincides with the sagittal plane of the system, during the rotation process, the image plane position of the system remains basically unchanged through the non-rotationally symmetric lens group; at any moment during the rotation process, the conjugate distance of the optical system in the reference surface is approximately equal to the initial moment, that is, it satisfies the relationship (2): （2）； wherein, is the image distance of the non-rotationally symmetric lens meridian, is the object distance of the non-rotationally symmetric lens meridian, is the equivalent principal plane distance of the non-rotationally symmetric lens, and the sum of the three is the conjugate distance of the non-rotationally symmetric lens meridian; is the image distance of the non-rotationally symmetric lens rotated by an arbitrary angle, is the object distance of the non-rotationally symmetric lens rotated by an arbitrary angle, is the equivalent principal plane distance of the non-rotationally symmetric lens rotated by an arbitrary angle, and the sum of the three is the conjugate distance of the non-rotationally symmetric lens rotated by an arbitrary angle; is the focal length of the non-rotationally symmetric lens meridian; The relationship (1) and the relationship (2) together ensure that the illumination spot has high uniformity, clear and sharp edges at any illumination angle.

4. A zoom laser illuminator of elliptical spot according to claim 1, characterized in that: The compensation group and the variable magnification group have the ability to move along the optical axis, by adjusting the relative positions of the variable magnification group and the compensation group, the focal length of the system is adjusted and the compensation of the image plane position is realized.

5. A zoom laser illuminator of an elliptical light spot according to claim 4, characterized in that: During the process of changing the illumination angle of the laser illuminator from small to large, the compensation group moves from away from the fiber end face to gradually close to the fiber end face, and the variable magnification group moves from close to the fiber end face to away from the fiber end face.

6. A zoom laser illuminator of elliptical spot according to claim 4, characterized in that: During the variable magnification process, the variable magnification group and the compensation group pass through the points with an imaging magnification of-1 at the same time.

7. A zoom laser illuminator of elliptical spot according to claim 1, characterized in that: The present zoom laser illuminator satisfies: , 、 respectively the longest and shortest focal length values of the system, D being the maximum clear aperture.

8. A zoom laser illuminator of elliptical spot according to claim 1, characterized in that: The fiber end face is the light emitting end face of a 400μm core diameter multimode fiber, and the fiber length is >1m.

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