Systems and Methods for Laser Scattering, Displacement, and Manipulation

Abstract

To provide systems and methods for scattering or deviating a laser beam.SOLUTION: A system utilizing a lenticular sheet and a laser source projecting a laser beam onto the lenticular sheet produces shapes such as laser cones. Minor adjustments of the laser source with respect to the lenticular sheet may vary the size and shape of the laser cone that provides improved Light Detection and Ranging (LIDAR) systems. A diffraction grating added to the path of the laser beam causes a laser pattern of a matrix of lines to be produced which also provides improvement. Interference between multiple lenticular sheets may be used to deviate a laser beam to protect military assets from laser-guided projectiles and / or laser acquisition.SELECTED DRAWING: Figure 20

Description

Technical Field

[0001] The present invention generally relates to the manipulation of light beams, and more particularly to systems and methods for laser scattering, deflection, and manipulation.

Background Art

[0002] A laser represents "light amplification by stimulated emission of radiation". Lasers differ from other light sources in that they emit light that is spatially and temporally coherent. Spatial coherence allows a laser to be focused into a narrow spot, enabling applications such as laser cutting and lithography. Spatial coherence also allows a laser beam to remain narrow over long distances (collimation), enabling applications such as laser pointers. Lasers can also have high temporal coherence, allowing them to emit light with an ultra-narrow spectrum, i.e., they can emit monochromatic light. Temporal coherence can be used to generate light pulses as short as 1 femtosecond.

[0003] A lenticular sheet is a translucent plastic sheet that has a series of vertically arranged plano-convex cylindrical lenses called lenticules on one side and a flat surface on the other side, and is produced by profiling and precision extrusion. Lenticules help convert a 2D image into various optical illusions, and an observer can see the lenticular special effect when the orientation of the lenticular sheet is changed. Lenticular sheets can be made from acrylic, APET, PETG, polycarbonate, polypropylene, PVC, or polystyrene. Each of these different materials has different levels of temperature and UV light sensitivity.

[0004] An important characteristic of a lenticular sheet is the lens density. The lens density is expressed as lenses per inch or line pairs per inch (LPI). The thickness of the lenticular sheet is often, but not always, inversely correlated with the LPI, such that the lower the LPI, the thicker the lenticular sheet. Another important characteristic of the lenticular sheet is the viewing angle. The viewing angle of the lenticular sheet is the V-shaped area within which the lenticular image can be clearly seen.

[0005] A diffraction grating is a plate of glass, plastic, or metal on which very closely spaced parallel lines are etched, and which produces a spectrum by the diffraction and interference of light. A diffraction grating is an optical component having a periodic structure that divides and diffracts light into several beams traveling in different directions. The resulting coloration is in the form of structural coloration. The direction of the beams depends on the grating spacing and the wavelength of the light, and as a result the grating acts as a dispersive element. A holographic diffraction grating is a very efficient embossed holographic optical element (HOE). Diffraction gratings are used for the direct viewing and analysis of spectra from various gas discharge tubes and other light sources. The pattern size is measured in lines per inch or lines per millimeter (mm), and is an important characteristic of the diffraction grating. Some diffraction gratings have 13,500 lines per inch. Uniaxial diffraction gratings have a plurality of parallel lines. Biaxial diffraction gratings have a first plurality of parallel lines and a second plurality of parallel lines perpendicular to the first plurality of parallel lines. Diffraction gratings are used in experiments related to the study of light and color.

[0006] A lidar (light detection and ranging) is a laser-based remote sensing technology. The theory behind lidar is to direct a laser beam at a surface and measure the time it takes for the laser to hit the object. Typically, an optical sensor located at or near the laser source detects these hits. Then, by knowing that the laser travels at the speed of light, multiplying the speed of light by the detection time and then dividing by 2, the distance to the detected surface can be determined. A lidar system thus utilizes at least one laser source and at least one sensor. The lidar system can be installed on the ground, underwater, in space, or mounted on an airplane, a vehicle, or a UAV (unmanned aerial vehicle).

Summary of the Invention

Means for Solving the Problems

[0007] In one aspect of the present disclosure, a system for deflecting a laser beam is provided. The system includes a laser source that emits an incident laser beam including a plurality of light rays projected as dots, and a lenticular sheet having a lens side including a plurality of parallel longitudinal lenticular lenses and a smooth side opposite the lens side. The laser source is directed toward the lens side of the lenticular sheet such that the incident laser beam hits at least one of the plurality of parallel longitudinal lenticular lenses. A first portion of the plurality of light rays of the incident laser beam is deflected by refraction to form a refracted beam of a first shape. A second portion of the plurality of light rays of the incident laser beam is reflected by at least one surface of the plurality of parallel longitudinal lenticular lenses to form a reflected beam of a second specific shape.

[0008] In one embodiment, the laser source is directed such that a first incident laser beam hits at least one of the plurality of parallel longitudinal lenticular lenses perpendicularly, the first portion of the incident laser beam deflected by refraction represents the majority of the plurality of light rays of the incident laser beam, and the refracted beam of the first specific shape is in the form of a triangular surface beam projected as a straight line.

[0009] In one embodiment, the lenticular sheet is installed in an upright position such that a plurality of parallel longitudinal lenses are horizontally oriented, the triangular surface beam is vertically oriented, and the projection line is vertical.

[0010] In one embodiment, the lenticular sheet is installed in an upright position such that a plurality of parallel longitudinal lenticular lenses are vertically oriented, the triangular surface beam is horizontally oriented, and the projection line is horizontal.

[0011] In one embodiment, the laser source is directed such that a first portion of a plurality of rays of a first incident laser beam that is redirected by refraction represents a majority of the plurality of rays of the first incident laser beam, the first incident laser beam is in the same plane as a horizontal plane passing through at least one of a plurality of parallel longitudinal lenticular lenses, and the incident laser beam strikes at least one of the plurality of parallel longitudinal lenticular lenses at a perpendicular angle of incidence such that a refracted beam of a specific shape is in the form of a curved surface projected as an arc.

[0012] In one embodiment, the laser source is directed such that the first incident laser beam strikes at least one of the plurality of parallel longitudinal lenticular lenses at an angle of incidence from a perpendicular direction such that the first and second portions together form a cone projected onto a circle.

[0013] In one embodiment, the lens side of the lenticular sheet is coated with a reflective material such that a second portion of a plurality of rays reflected by at least one surface of a plurality of longitudinal lenticular lenses includes all of the plurality of rays of the incident laser beam.

[0014] In one embodiment, an anti-reflection layer or coating is provided on at least one of the lens side and the smooth side of the lenticular sheet to reduce a second portion of a plurality of rays of the incident laser beam reflected by at least one surface of a plurality of longitudinal lenticular lenses.

[0015] In one embodiment, the system further comprises at least one diffraction grating positioned between the laser source and the lenticular sheet such that the incident laser beam passes through the diffraction grating before passing through the lenticular sheet.

[0016] In one embodiment, the system further comprises at least one diffraction grating positioned after the lenticular sheet such that the incident laser beam passes through the diffraction grating after passing through the lenticular sheet.

[0017] In one embodiment, the lenticular sheet is installed in an upright position such that a plurality of parallel longitudinal lenses are horizontally oriented, and at least one diffraction grating includes at least one linear diffraction grating oriented such that its plurality of lines are vertically oriented.

[0018] In one embodiment, the lenticular sheet is installed in an upright position such that a plurality of parallel longitudinal lenses are oriented at an angle to the horizontal plane, and at least one diffraction grating includes at least one linear diffraction grating oriented such that its plurality of lines are vertically oriented.

[0019] In one embodiment, the lenticular sheet is installed in an upright position such that a plurality of parallel longitudinal lenses are horizontally oriented, and at least one diffraction grating includes at least one biaxial diffraction grating oriented such that its first plurality of lines are vertically oriented and its second plurality of lines are horizontally oriented.

[0020] In one embodiment, the lenticular sheet is installed in an upright position such that a plurality of parallel longitudinal lenses are oriented at an angle to the horizontal plane, and at least one diffraction grating includes at least one biaxial diffraction grating oriented such that its first plurality of lines are vertically oriented and its second plurality of lines are horizontally oriented.

[0021] In another aspect of the present disclosure, a system for manipulating two laser beams to form a cone is provided. The system includes a first laser source that generates a first incident beam composed of a plurality of light rays projected onto dots, a second laser source that generates a second incident beam composed of a plurality of light rays projected onto dots, and a double-sided lenticular sheet having a first lens side including a plurality of parallel longitudinal lenticular lenses and a second lens side opposite the first lens side including a plurality of parallel longitudinal lenticular lenses. The first laser source is directed toward the first side of the lenticular sheet such that the first incident beam hits one of the plurality of parallel longitudinal lenticular lenses at an incident angle such that most of the first incident beam rays are reflected to form a first curved surface. The second laser source is directed toward the second side of the lenticular sheet such that the second incident beam hits the opposite side of one of the plurality of parallel longitudinal lenticular lenses at the same incident angle as the first laser source such that most of the second incident beam rays are refracted to form a second curved surface. The first and second curved surfaces together form a cone projected as a circle.

[0022] In one embodiment, the double-sided lenticular sheet includes first and second single-sided lenticular sheets each having a lens side and a smooth side, and the first and second single-sided lenticular sheets are positioned back-to-back on their respective smooth sides.

[0023] In one embodiment, the system further includes a sheet of bright opaque material provided between the respective smooth sides of the first and second single-sided lenticular sheets.

[0024] In one embodiment, the sheet of bright opaque material includes a double-sided mirror.

[0025] In one embodiment, the first lens side and the second lens side are coated or fabricated with a reflective material.

[0026] In one embodiment, the smooth sides of the first and second single-sided lenticular sheets are coated with a reflective material.

[0027] In yet another aspect of the present disclosure, a system for manipulating two laser beams to form a cone is provided. The system includes a first laser source that generates a first incident beam composed of a plurality of light rays projected onto a dot, a second laser source that generates a second incident beam composed of a plurality of light rays projected onto a dot, and a lenticular sheet having a first lens side including a plurality of parallel longitudinal lenticular lenses and a second lens side opposite the first lens side including a plurality of parallel longitudinal lenticular lenses. The first laser source is directed toward the first side of the lenticular sheet such that the first incident beam hits one of the plurality of parallel longitudinal lenticular lenses at a first incident angle such that the first incident beam rays are refracted and reflected to form a first cone. The second laser source is directed toward the second side of the lenticular sheet such that the second incident beam hits the opposite side of one of the plurality of parallel longitudinal lenticular lenses at an incident angle greater than the first incident angle such that the second incident beam rays are refracted and reflected to form a second cone that is larger than and coaxial with the first cone.

[0028] In one embodiment, the first and second beams are separated when they hit one of the plurality of parallel longitudinal lenticular lenses such that there is a distance between the apex of the first cone and the apex of the second cone.

[0029] In yet another aspect of the present disclosure, a method for detecting at least one object using a light detection and ranging (lidar) system is provided. The method includes projecting a first incident laser beam at a first angle onto a first lens side of a dual-sided lenticular sheet to generate a first half-cone of reflected light rays, projecting a second incident laser beam at a second angle onto a second lens side of the dual-sided lenticular sheet to generate a second half-cone of reflected light rays that, together with the first half-cone of reflected light rays, forms a full cone of reflected light rays, and detecting, by at least one sensor of the lidar system, a signal reflected from the at least one object when the at least one object crosses any one of the full cone of reflected light rays.

[0030] In one embodiment, the method further includes changing the first angle and the second angle, respectively, to vary the sizes of the first half-cone and the second half-cone.

[0031] In yet another aspect of the present disclosure, a system for redirecting a laser beam is provided. The system includes a laser source for projecting an incident laser beam, a first lenticular sheet having a lens side including a plurality of parallel longitudinal lenticular lenses and a smooth side opposite the first side, and a second lenticular sheet having a lens side including a plurality of parallel longitudinal lenticular lenses and a smooth side opposite the first side. The first and second lenticular sheets are positioned such that the smooth side of the first lenticular sheet faces the smooth side of the second lenticular sheet, and the first and second lenticular sheets form a dual-sided lenticular sheet. The laser source projects the incident laser beam through the first and second lenticular sheets.

[0032] In one embodiment, the second lenticular sheet is positioned such that its plurality of lenticular lenses are parallel to and offset from the plurality of lenticular lenses of the first lenticular sheet so as to create an interference pattern between the two lenticular sheets to deflect the laser beam.

[0033] In one embodiment, the second lenticular sheet is positioned such that its plurality of lenticular lenses are angled with respect to the plurality of lenticular lenses of the first lenticular sheet so as to create an interference pattern between the two lenticular sheets to deflect the laser beam.

[0034] In one embodiment, the system further comprises a double-sided lenticular sheet having a first lens side including a plurality of parallel longitudinal lenticular lenses and a second lens side opposite the first side including a plurality of parallel longitudinal lenticular lenses, the double-sided lenticular sheet being positioned in front of or behind the first and second lenticular sheets with respect to the laser source.

[0035] In one embodiment, the first and second lenticular sheets are integrally formed.

[0036] In one embodiment, the first and second lenticular sheets and the double-sided lenticular sheet are integrally formed.

[0037] A method of fabricating a system for deflecting a laser beam includes providing a first lenticular sheet having a lens side including a plurality of parallel longitudinal lenticular lenses and a smooth side opposite the first side, providing a second lenticular sheet having a lens side including a plurality of parallel longitudinal lenticular lenses and a smooth side opposite the first side, and attaching the smooth side of the first lenticular sheet to the smooth side of the second lenticular sheet.

[0038] In one embodiment, before the attaching step, the method further includes positioning a second lenticular sheet such that its plurality of lenticular lenses are parallel to and laterally offset from the plurality of lenticular lenses of the first lenticular sheet.

[0039] In one embodiment, before the attaching step, the method further includes positioning a second lenticular sheet such that its plurality of lenticular lenses are angled with respect to the plurality of lenticular lenses of the first lenticular sheet.

[0040] In one embodiment, the method includes providing a double-sided lenticular sheet having a first lens side including a plurality of parallel longitudinal lenticular lenses and a second lens side opposite the first side including a plurality of parallel longitudinal lenticular lenses, and attaching the double-sided lenticular sheet to the lens side of the first lenticular sheet or the lens side of the second lenticular sheet such that the plurality of parallel longitudinal lenticular lenses of the double-sided lenticular sheet are parallel to either the plurality of parallel longitudinal lenticular lenses of the first lenticular sheet or the plurality of parallel longitudinal lenticular lenses of the second lenticular sheet.

[0041] Embodiments of the present invention will be presented with reference to the accompanying drawings.

Brief Description of the Drawings

[0042]

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Best Mode for Carrying Out the Invention

[0043] Embodiments of the present invention will be presented here not by way of limitation but merely by way of example. By utilizing a lenticular lens, the beam path of one or more laser elements can be significantly changed to change the laser beam from the point where the beam hits the lenticular lens into a plane, a shallow curved surface, a deep curved surface, or a cone.

[0044] Referring to FIG. 1, a system 100 for manipulating a laser beam is depicted. System 100 includes a laser source 110 that emits an incident laser beam 120 which forms dots when projected onto a surface. The incident laser beam 120 is directed perpendicular to a linear lenticular sheet 150. The linear lenticular sheet 150 has a lens side 151 and an opposite smooth side. The lens side 151 of the linear lenticular sheet 150 includes a plurality of longitudinal lenticular lenses 155 oriented in the horizontal direction. The incident laser beam 120 is generally narrow and focused, and it is projected onto a single longitudinal lenticular lens 155 on the lens side 151 of the lenticular sheet 150, or onto a few adjacent lenticular lenses 155. This depends on the density of the lenticular sheet 150, measured in lenses per inch or LPI. For a lenticular sheet with a low lens density, all of the rays of the incident laser beam 120 can hit a single longitudinal lenticular lens 155. However, for a lenticular sheet 150 with a high lens density, the rays of the incident laser beam 120 hit a plurality of adjacent lenticular lenses 155. The individual rays of the incident laser beam 120 are refracted at different angles by one or more longitudinal lenticular lenses 155 each. The resulting rays 125 are turned so that they are diffused, and are projected from the opposite smooth side of the lenticular sheet 150 in the form of a plurality of rays that form a triangular plane 128. Upon projection onto a plane, the turned rays 125 form a vertical line pattern 130. The lenticular sheet used in FIG. 1 has a relatively high lens density. Further observation of line 130 reveals that line 130 is composed of a plurality of closely spaced dots. A few rays 127 of the incident laser beam 120 are reflected from the surface of the lenticular lens 155 in the form of a very narrow triangular plane. The rays 127 form small lines 132 when projected onto a plane on the same side as the laser source 110.

[0045] The orientation of the line pattern 130 formed by the divergence of the incident laser beam 120 due to the refraction of its light rays through one or more longitudinal lenticular lenses 155 depends on the orientation of the one or more longitudinal lenticular lenses 155 onto which the incident laser beam 120 is projected. In FIG. 1, the lenticular sheet is oriented such that the lenticular lenses 155 are horizontally oriented, and the resulting line pattern 130 is vertical. FIG. 2 depicts the system 100 and is similar to the system 100 of FIG. 1 except that the lenticular sheet 150 is installed in an upright position and the plurality of longitudinal lenticular lenses 155 are oriented vertically. When the laser source 110 projects the incident laser beam 120 onto one or more vertically oriented longitudinal lenticular lenses 155 of the lenticular sheet 150, the light rays of the incident laser beam 120 are refracted by the lenticular lenses 155 to produce redirected light rays 126 in the form of a triangular plane 129. When projected onto a plane, the light rays 126 form a horizontal line pattern 135 behind the smooth side of the lenticular sheet 150. The lenticular sheet 150 used in FIG. 2 has a low lens density, and thus the line pattern 135 is illustrated as a single line. However, similar to the line pattern 130, the line pattern 135 is composed of a plurality of closely spaced dots.

[0046] In both FIG. 1 and FIG. 2, the laser beam 120 is perpendicular to the lenticular sheet. Therefore, the effect of the lenticular lens 155 on the laser beam 120 is symmetric. FIG. 3 depicts a system 100 for turning the laser beam 120, similar to that of FIG. 1, except that the laser beam 120 is directed at a horizontal incident angle θ with respect to the vertical direction to the lens side 151 drawn by the line 184. The incident angle θ is such that the overwhelming majority of the rays of the incident laser beam 120 are refracted by one or more longitudinal lenticular lenses 155 in the form of the turned rays 135. Only a small number of the rays of the incident laser beam 120 are reflected by one or more longitudinal lenticular lenses 155 in the form of the reflected rays 137. The incident laser beam 120 is maintained in a horizontal plane passing through the lenticular lens 155 it is directed at. The angled orientation of the laser beam 120 with respect to the lenticular lens 155 causes the individual rays of the laser beam 120 passing through the lenticular lens 155 to be refracted in two different general directions. Due to the curved (convex) shape of the lenticular lens 155, the rays of the laser beam 120 tend to be turned (refracted) vertically as seen in FIG. 1. Moreover, due to the incident angle θ at which the laser beam 120 is oriented with respect to the direction perpendicular to the lenticular lens 155, the individual rays of the laser beam 120 tend to be additionally refracted horizontally. Since the rays of the incident laser beam 120 hit different regions of the lenticular lens 155 each having a slightly different thickness (due to the curvature of the lenticular lens surface), each of the rays of the laser beam 120 is thus refracted by a different angle horizontally. As a result, the turned rays 135 emerging from the smooth side of the lenticular lens 155 will ultimately take the shape of a curved surface 138 (in the form of a partial cone) that projects an arc pattern 140 when hitting a plane. A small portion of the rays of the incident laser beam 120 is reflected from the lens side surface of the lenticular lens 155. The reflected rays 137 form a curved surface on the same side as the laser source 110 of the lenticular sheet 150. When projected onto a plane, the reflected rays 137 project a small arc 142.

[0047] Figure 4 depicts a system 100 similar to the system of FIG. 3, except that the angle of incidence θ of the beam 120 on the lenticular sheet 150 is greater than that of FIG. 3 with respect to the perpendicular 184. As the angle of incidence θ is increased, the majority of the rays of the incident laser beam 120 are reflected from the lens side of the lenticular lens 155 surface and are illustrated as the reflected rays 137. The reflected rays 137 form a curved surface that projects as an arc 162 in the shape of a partial ellipse. The curved surface formed by the reflected rays 137 and the corresponding projected arc 162 are on the same side of the lenticular sheet 150 as the laser source 110 in front of the sheet 150. Depending on the angle of incidence θ of the incident laser beam 120 with respect to the perpendicular 184, a smaller number of rays pass through the lenticular lens 155, are refracted curvilinearly as described above, and project an arc 160 behind the lenticular sheet 150. The resulting projected pattern is an ellipse 165 composed of the arcs 160 and 162 that complement each other. The ellipse 165 is the projection of an elliptical cone formed by the reflected rays 137 and the refracted rays. When the lenticular sheet is perpendicular to the surface (e.g., a wall) onto which the laser pattern is projected, the ellipse 165 projects close to a perfect circle, and thus, as illustrated in FIG. 5A, it has been observed that the reflected rays 137 and the refracted rays 135 together form a complete cone.

[0048] FIG. 5A illustrates a variation of the system 100 of FIG. 4. The incident laser beam 120 has an incident angle of θ with respect to the vertical direction 184 to the lenticular lens 155 of the lenticular sheet 150. Additionally, the incident laser beam 120 is angled by an angle β with respect to the horizontal plane passing through the lenticular lens 155, depicted as the plane passing through lines 184 and 185. The surface onto which the resulting refracted ray 135 and reflected ray 137 are projected is perpendicular to the lenticular sheet 150. Thus, the refracted and reflected rays form a shape close to a true circular cone 180 that projects as a circle composed of arcs 160 and 162. Due to the angle β, as shown, the circle is shifted upward with respect to the lenticular sheet 150. The rays 135 and 137 are shaped together like the cone 180 that projects a circle, however, the cone is partially projected in front of and partially behind the lenticular sheet 150 due to the fact that it is formed partially from the reflected ray and partially from the refracted ray. Thus, a laser cone can be formed by using the laser source 110 and the lenticular sheet 150. The cone can be directed up and down by varying the angle β with respect to the horizontal plane as described.

[0049] FIG. 5B is an upper perspective view illustrating the laser beam 120 being directed at a wide angle towards the lens side of the lenticular sheet 150, where the lenticular lens 155 is parallel to the horizontal plane passing through the laser beam 120. The left arc 162 is generated by the beam 120 reflected from the lenticular lens 155 on the left (lens) side of the sheet 150 in the form of the reflected ray 127 that projects as the arc 162. Conversely, the right refracted arc 160 is generated by the beam 120 that refracts through the lenticular lens 155 and exits from the smooth side of the lenticular sheet 150 as the ray 125 that projects as the arc 160.

[0050] From the above results, it becomes clear that as the beam diffuses from the lenticular material into shapes such as lines 130 and 135, arcs 140 and 142, and arcs 160 and 162, a laser surface or cone can be generated. Unlike some prior art methods where an incident laser beam is utilized to generate a shape by rotating a mirror, the system 100 presented herein has no moving parts. By simply varying the angle of the laser beam with respect to the lenticular sheet, various line, arc, and cone shapes can be generated.

[0051] Whereas the previous figure illustrated the laser beam being directed towards the lens side of the lenticular sheet, it should be noted that the present system was operated while projecting the laser beam towards the smooth side of the lenticular sheet instead. For example, referring to FIG. 6, the beam 120 is directed towards the smooth side 152 of the single-sided lenticular sheet 150. In this case, the left arc 160 formed is refracted through the sheet and is due to the beam emerging from the lenticular lens 155 on the lens side of the sheet as the ray 135 forming the arc 160. Conversely, the right arc 162 in the figure is formed by the laser beam 120 reflected from the smooth side of the lenticular sheet 150 as the ray 137 forming the arc 162. Additionally, a bright dot 167 is also formed at the center of the arc 162 by the beam 120 that has undergone specular reflection from the smooth side of the lenticular sheet 150. It has been observed that the refracted arc 160 is brighter than the reflected arc 162. The exception is the bright dot 167 on the reflected arc. This reveals that it is preferred to generate the laser cone using the lens side 151 of the lenticular sheet. It has also been observed that as the beam 120 is angled only slightly with respect to the lenticular sheet 150, the bright dot 167 is movable along the arc 162. Furthermore, as the angle of the beam 120 with respect to the smooth surface of the lenticular sheet 150 approaches being perpendicular to that surface, the intensity of the bright dot 167 increases. The observation made regarding the movable bright dot 167 along the arc 162 is an indication that a small change in the angle of the incident laser beam 120 with respect to the lenticular lens 155 rotates the rays 137 and 135. Essentially, changing the incident angle is sizing the cone, and in this case, all the dots on the arcs 160 and 162 rotate circumferentially as the cone is sized and they expand or contract. For example, by decreasing the incident angle θ by a small amount, a slightly larger cone 180 is generated for the rays 137 and 135. As the individual dots forming the arcs 160 and 162 move towards their new positions, they are also moving circumferentially.When the incident angle θ is increased, the opposite occurs, the cone 180 shrinks, and the individual dots forming the arcs 160 and 162 rotate in the opposite direction as they move to new positions. This has been confirmed to also apply when the incident laser beam is directed towards the lens side 151 of the lenticular lens. The rotation of the dots (and thus the beams projecting the dots) was initially observed with respect to the smooth side 152 due to the presence of the bright dot 167, however it applies to all dots forming the arcs 160 and 162. Thus, fine adjustment of the incident angle θ can be used to move the points circumferentially. This has significant advantages with respect to describing the application of the generated laser cone.

[0052] There is an advantage in diffusing the laser beam and / or projecting various lines, arcs and elliptical shapes having a laser light beam in the form of a laser surface, curved surface or cone. For example, security systems using a narrow, focused laser beam appear to be triggered by any small object that blocks the beam. Thus, many false positive triggers can occur for insects, birds or rodents passing through the beam. However, if the beam is diffused into a surface (projected as a line), a curved surface (projected as an arc) or a cone (projected as a circle), a larger object such as a human, drone or vehicle may be required to block a larger portion of the beam and trigger an alert condition. Since the conditions can vary or change for different areas, the size of the surface and cone can also be changed. Advantageously, changing the dimensions of the laser surface or cone is a simple matter of changing the angle and / or position of the projection of the incident laser beam onto the lenticular lens. Additionally or alternatively, different lenticular sheets with different viewing angles or lens densities (LPI) can be used. For example, for one or more of the same laser beams projected at the same angle, lenticular sheets with different viewing angles can produce projected laser cones or surfaces of different dimensions.

[0053] Referring to FIGS. 7A and 7B, a system 200 for projecting a laser cone 180 is provided. The system 200 is composed of two laser sources 210a and 210b and a double-sided lenticular sheet 170. The double-sided lenticular sheet 170 has a plurality of longitudinal lenticular lenses 175 on both of its sides. The laser source 210a projects an incident laser beam 220a having a first color, and the laser source 210b projects an incident laser beam 220b having a second color different from the first color. For example, the laser beam 220a may be green while the laser beam 220b may be red. Both the incident laser beams 220a and 220b are directed to the opposite side of the double-sided lenticular sheet 170 and at different incident angles. The incident laser beam 220a is reflected from one side of the lenticular lens 175a of the lenticular sheet in the form of a light ray 137. When the light rays 137 hit or contact a plane, they project an arc 180a in front of the lenticular sheet 170. The incident laser beam 220b, on the other hand, is projected to the opposite side of the lenticular lens 175a at a smaller incident angle with respect to the vertical direction of the lenticular sheet 170. Therefore, the beam 220b is projected to the rear side of the lenticular sheet 170 and is reflected from the lenticular lens 175a. The light rays reflected from the lens 175a and reflected as the light rays 135 form a curved surface such as a partial cone and project an arc 180b in front of the lenticular sheet. Advantageously, the two arcs 180a and 180b are complementary as long as the two beams are projected to the opposite sides of the same location of a specific lenticular lens of the double-sided lenticular sheet 170. The resulting light ray configuration composed of the light rays 135 and 137 is in the shape of a cone 180. The incident angle of the incident laser beam 220a is selected such that most of the light rays are reflected as the light ray 137, while the angle of the incident laser beam 220b is selected such that most of the light rays are reflected as the light ray 135 with a higher concentration. If the incident angle of the laser source 210a is large enough, the laser beam 220a will pass through the lenticular sheet 170 and be refracted arcuately to the other side near the arc 180b or onto the arc 180b.

[0054] In FIG. 7B, the incident angles of the incident laser beams 220a and 220b are both large such that both beams are reflected from the respective surfaces of the double-sided lenticular lens 170. The resulting laser cone 180 is thus very thin but is composed entirely of reflected light rays.

[0055] FIG. 8A illustrates a system 300 in which two laser sources 310a and 310b project laser beams 320a and 320b of the same color. Thus, the resulting cone 180 appears to be from the same laser source even though it is a composite of the reflected rays 137 from the incident laser beam 320a and the refracted rays 135 from the incident laser beam 320b. The result is a laser cone 180 composed of two half-laser cones 180a and 180b that are monochromatic. The laser cone 180 has several useful applications as shown below.

[0056] FIG. 8B illustrates that when the laser cone 180 generated, for example, by the system 300 of FIG. 8A is projected onto a surface far from the laser source, it is actually composed of a plurality of rays projected as circumferential dots 182. A typical arc and cone are composed of hundreds of dots. However, as described with respect to FIG. 6, fine adjustment of the incident angle of the incident laser beam rotates the dots 182 in the circumferential direction (clockwise or counterclockwise). Thus, as will be described later, this can be used to detect an object that can normally pass undetected between the rays projecting those dots.

[0057] LiDAR (Light Detection and Ranging) currently utilizes one or more pulsed lasers that reflect signals from the surrounding environment and a sensor to detect the reflected signals. Thus, by measuring the time it takes for the signal to reflect and return to the sensor, a computer can determine the distance to an object and / or create a three-dimensional map of the surrounding area and surface characteristics. Topographic lidar uses near-infrared lasers to create maps of the land, and bathymetric lidar uses green lasers to penetrate water and create maps of the seabed and riverbed. However, the use of lidar in water is often limited to just a few dozen feet. Lidar is a key element in autonomous vehicles, and the more accurate the lidar, the safer the system can be. Lidar is also being tested in aircraft to determine areas of turbulence in front of the aircraft and allow the aircraft to avoid or prepare for those areas. Lidar can be used by civilian organizations or the military to search for targets in shallow water, on the ground, or in the air (clear weather) or in space. Low-observable aircraft, drones, birds, and bats are difficult to detect by radar but can be detected by this type of system.

[0058] Utilizing the above system, instead of laser points, planes, curved surfaces, and / or cones can be created so that more details can be determined by the sensor to achieve results in a shorter period, and a larger angle can be achieved than current lidar systems. In one embodiment, to scan a large empty portion, the laser cone can be variably adjusted from narrow to wide, while the sensor can receive any reflections from other aircraft, aircraft clouds, aircraft turbulence, natural turbulence, drones, missiles, projectiles, rockets, bullets, balloons, birds, bats, or swarms of insects.

[0059] Figure 8C illustrates the use of a laser cone 180, composed of a plurality of light rays 137 generated by an on-board lidar system, to detect ground troops. Figure 8D illustrates a laser cone used by a sniper using a lidar system to detect one or more enemy troops. Figure 8E illustrates a land-based lidar system that utilizes three laser cones 180 each composed of a plurality of light rays 137. The land-based lidar is used to detect missiles. Figure 8F depicts a laser cone generated by an on-board lidar system used to detect enemy aircraft. Figure 8G depicts the land-based lidar system projecting a cone 180 for detecting aircraft. The cones illustrated in Figures 8C through 8G are composed of a plurality of light rays as described above and are projected as circles as illustrated in Figure 8B. Typical arcs and cones are composed of hundreds of dots. To ensure that an object to be detected does not pass between two circumferentially adjacent light rays, the light rays are moved circumferentially such that each light ray draws an arc between its current location and the location of an adjacent light ray. In one embodiment, this is accomplished by fine adjustment of the laser source that varies the angle of incidence of one or more incident laser beams with respect to a lenticular lens. In another embodiment, a lenticular sheet is slightly moved or rotated to vary the angle of incidence of one or more incident laser beams such that the refracted light rays are slightly rotated circumferentially as described.

[0060] FIG. 9A illustrates a system 200 consisting of a dual-sided lenticular sheet 170 and two laser sources 210a and 210b. Laser source 210a projects an incident laser beam 220a, and laser source 210b projects an incident laser beam 220b. The laser beam 220a generates reflection arcs 270a and refraction arcs 270b, as described previously. Similarly, the laser beam 220b generates reflection arcs 280a and refraction arcs 280b. The laser beam 220b is angled at a greater angle than that of the laser beam 220a in the vertical direction 184 to the lenticular sheet 170. Thus, the arcs 280a and 280b generated by the incident laser beam 220b are larger in dimension than the arcs 270a and 270b generated by the incident laser beam 220a. As a result, the laser cone 280 formed by the reflected and refracted rays from the beam 220b is larger than the laser cone 270 formed by the reflected and refracted rays from the beam 220a. Since the beams 220a and 220b are projected on each side of the same lenticular lens, the two cones are coaxial. In the depicted embodiment, the laser beams are directed at different lateral points of the lenticular lens, which are horizontally separated by a distance (d). The resulting cones are, therefore, nested such that an object traveling inside the cone 280 can be detected by the cone 270. The laser source 210a can be moved in the horizontal plane to change the distance (d). Thus, the size and position of the cone 270 with respect to the cone 280 change. The resulting effect is that the entire volume between the cones 270 and 280 can be swept and covered by the laser rays that can be used to detect any object between the cones.

[0061] In one embodiment, the laser source 210a can be moved back and forth, for example, to sweep the volume between cones 270 and 280. Additionally, the laser source 210a can have its angle of incidence slightly changed to rotate the light rays forming cone 270. For example, referring to FIG. 9B, dot 271 represents the light rays of cone 270 when projected onto a plane. Similarly, dot 281 represents the light rays of cone 280 when projected onto a plane. If the laser source 210a is moved such that the distance (d) in FIG. 9A becomes smaller as cone 270 expands, dot 271 approaches dot 281. Further, if the laser source 210a is slightly angled to rotate each dot 271 to a location previously occupied by an adjacent dot, the volume between cones 270 and 280 is completely covered both radially and circumferentially for object detection. In another embodiment, the laser source 210b is moved such that cone 280 becomes smaller, and the laser source 210a is moved such that cone 270 becomes smaller until it almost disappears. This is done by angling the laser source 210a to a large obtuse angle (close to 180 degrees) from the perpendicular direction to the lenticular sheet 170. Thus, the entire volume encompassed by the laser cone 280 is swept for object detection. For example, cone 270 can be half the size of cone 280, and it can take the same amount of time for cone 280 to decrease in size until it matches the initial size of cone 270 as it takes for cone 270 to almost disappear. During that time, the entire volume of cone 280 is swept radially. Alternatively, a smaller number of additional laser sources can be added, and their respective beams can also be directed to be displaced from each other by a distance such as (d). Thus, several concentric cones can be utilized to cover the volume encompassed by the outermost laser cone 280. In such an embodiment, it may not be necessary to change the size of the laser cones, and it may be sufficient to simply rotate them such that each cone region is swept circumferentially.

[0062] The fixed laser cone can also be rotated, rather than varying the cone angle, as can be done with a radar or lidar. Lidars often use mirrors to rapidly rotate the laser source, but the same can occur with these lines, arcs, or cones. Combinations of cone rotation and variable cone angles from narrow to wide can also be used, and to increase the scanned range, two or more lasers can be used for multiple cones at the same or different angles and can be used with the same lens or other lenses. Two or more lasers can be used for multiple cones with variable angles, and the laser cones can be fixed. In space, this system can be used to detect other space-based objects, whether natural (meteorites, asteroids, comets, etc.) or artificial (satellites, spacecraft, astronauts, space junk, etc.).

[0063] Referring to FIG. 10A, a system 100 similar to that shown in FIGS. 1 - 6 can be used to generate a partial laser cone that projects as arc 140. Laser source 110 projects an incident laser beam 120 that is angled by a large angle θ with respect to a line 184 perpendicular to the surface of the lens side 151 of a single-sided lenticular sheet such as sheet 150. This generates only the reflection of the rays of the incident laser beam 120 in the form of reflected ray 127 that projects as arc 140. As described above, by further increasing the angle θ, the arc will ultimately disappear completely.

[0064] To generate a circular cone generated only by the reflection of the laser beam from the double-sided lenticular sheet 170, it has been observed that the incident angle of the incident laser beam 120 needs to be large with respect to the perpendicular direction to the lenticular sheet. If the angle is not large enough, part of the light ray is refracted and the other part is reflected. The resulting pattern can be two cones instead of one. In the system illustrated in FIG. 10B, the double-sided lenticular sheet 170 is replaced with two back-to-back single-sided lenticular lens sheets 150 and a sheet 160 or mirror of a bright opaque material inserted therebetween. In this configuration, the bright opaque material or mirror prevents the refraction of the laser beam through the lenticular lens sheet and instead reflects the beam. Thus, since the angle can be larger than, for example, the angle used in FIG. 10A, the resulting pattern can be a larger cone.

[0065] FIG. 10C illustrates a system similar to that of FIG. 10B, but uses two back-to-back lenticular sheets 250 each having a highly reflective lens side. For example, the lenticular lenses of the lenticular sheet 250 may be made of a highly reflective material or have a highly reflective coating. The high reflectivity on the lens side prevents the refraction of the laser beam through the lenticular lens sheet and instead reflects the beam. Thus, since the angle can be larger than, for example, the angle used in FIG. 10A, the resulting pattern can be a larger cone.

[0066] The laser source can be moved slightly left or right with respect to the lenticular sheet to move the dots clockwise or counterclockwise. If each projected dot is close to its adjacent ones, only a very slight movement by the laser source may be required to traverse the interval to the next adjacent dot position for each dot. Another possible embodiment is to move the lenticular sheet itself. Only a very slight movement by the sheet is required to move the dots and traverse the interval. In one embodiment, the lenticular sheet may be in the form of a cylinder and be slightly movable. A simple gear and spring mechanism can be utilized to produce a slow and steady movement. For example, a winding mechanism similar to an old wind-up pocket watch can be used. The mechanism may include a reduction gear device to provide a slow but steady turning motion to rotate one of the lenticular materials used to turn the laser source and the laser beam of the laser source. If the same mechanism is applied to the first laser source to move it slightly left or right, when the first laser source reaches the left or right end point while the second laser is in the middle of the sweep, the second laser source may be required to cancel the stop of the dot. By utilizing a rotating mirror, lines, arcs or cones can also be rotated.

[0067] Experimentally, it has been revealed that regardless of the shape, a stealth aircraft cannot effectively scatter the electromagnetic energy existing at the small wavelengths of the light emitted by a lidar. A high-speed jet aircraft or a new hypersonic missile may be able to fly through the interval between the described deflected laser beams. However, it seems less likely to do so if the beams forming the described cones are also achieved by moving the lenticular lens or the laser source and are moving clockwise or counterclockwise. Additionally, the turbulence generated by such a flying object can also be detected by a lidar.

[0068] Figure 11 depicts a method 1100 for detecting an object using a lidar system. At step 1110, a first incident laser beam is projected onto the first lens side of a double-sided lenticular sheet to generate a first half-cone of reflected light rays. At step 1120, a second incident laser beam is projected at a second angle onto the second lens side of the double-sided lenticular sheet to generate a second half-cone of reflected light rays that, together with the first half-cone of reflected light rays, forms a full-cone of reflected light rays. At step 1130, a sensor of the lidar system detects a signal reflected from the object when the object crosses any one of the full-cone of reflected light rays.

[0069] Figure 12 is a top view of the diffractive side of a linear (uniaxial) diffraction grating 1000 having a plurality of lines 1010. The opposite side of the diffraction grating 1000 is a smooth plane. Figure 13 is a top view of the diffractive side of a biaxial diffraction grating 1500 having a plurality of horizontal lines 1010 and a plurality of vertical lines 1020. The opposite side of the biaxial diffraction grating 1500 is a smooth plane.

[0070] Figure 14 illustrates an incident light beam 20 being directed at an angle to the normal towards the smooth surface of the diffraction grating 1000. Rays of light of different colors including the beam 20 are refracted in the same way as they are refracted from a prism and decomposed into different-colored light rays 21, 22, 23, and 24.

[0071] Figure 15 is a side perspective view illustrating an incident laser beam 120 being directed through a uniaxial diffraction grating 1000. The uniaxial diffraction grating 1000 causes the beam 120 to generate a plurality of diffracted laser beams 1024 that, when projected onto a plane such as a wall, generate a plurality of dots 1025 arranged in a row along its surface. It has been observed that three dots were formed using a particular type of laser source and a diffraction grating with 1000 lines per millimeter (l / mm).

[0072] FIG. 16 is a side perspective view illustrating an incident laser beam 120 being directed through a biaxial diffraction grating 1500. The biaxial diffraction grating 1500 causes the beam 120 to generate a plurality of diffracted laser beams 1024 that, when projected onto a plane such as a wall, generate a plurality of dots 1025 arranged in a matrix pattern on its surface.

[0073] Returning to FIG. 1, when an incident laser light beam 120 is directed substantially perpendicular to a linear lenticular sheet 150 in which a lenticular element 155 is horizontally oriented, the resulting pattern is a beam that is formed as a triangle and projected as a perpendicular line 130 to the plane. Each perpendicular line 130 is actually composed of hundreds of dots that are closely spaced. If a plurality of laser beams 1024 from FIG. 15 are passed through a lenticular sheet 150 such as that in FIG. 1, each individual one of the diffracted laser beams 1024 in FIG. 15 will generate a line such as line 130 in FIG. 1. Referring to FIG. 17, a laser source 110 directs an incident laser beam 120 through a linear lenticular sheet 150 that is horizontally oriented and installed adjacent to and behind a diffraction grating 1000, following a linear diffraction grating 1000 that is oriented such that the diffracted lines are perpendicular. The resulting pattern is a plurality of triangular vertical planes projected as perpendicular lines 1080. A precise inspection of the perpendicular lines reveals that each line is formed from hundreds of closely spaced points. The number of perpendicular lines depends on the pattern density of the diffraction grating. Thus, the number of projected perpendicular lines can be increased.

[0074] Regarding FIG. 18, if the lenticular lens sheet 150 is rotated so that it is angled with respect to the diffraction grating 1000, the points projected by the diffraction grating are no longer vertically aligned, and each of them generates a line when passed through the linear lenticular sheet. The resulting pattern is projected as slanted lines 1090 and is the same number of slanted triangular laser planes that are closely spaced. Also, each of the slanted lines 1090 is composed of hundreds of points.

[0075] The diffraction grating used in FIG. 19 is a biaxial diffraction grating 1500 in accordance with an embodiment of the present disclosure. As previously described with respect to FIG. 16, when the incident laser beam 120 is projected through the biaxial diffraction grating 1500, a matrix of laser beams is formed that projects as a matrix of laser dots. For example, if the biaxial diffraction grating has a line pattern density of 13,500 lines per inch, it was observed that a 13×13 dot matrix pattern was projected by the diffracted laser beam. If a lenticular sheet 150 with multiple lenses is placed in the path of the diffracted laser beam 1024, each beam generates a line as previously illustrated. If the lenticular sheet is placed such that the lenticular lenses are oriented horizontally, many of the lines 1080 are aligned and several substantially bright lines are visible.

[0076] In FIG. 20, the lenticular sheet 150 is rotated by an angle with respect to the biaxial diffraction grating 1500. Thus, the matrix of dots generated by the diffraction grating is now oriented obliquely with respect to the lenticular sheet 150. The resulting pattern is a plurality of lines 1090 that are oblique. There are more lines 1090 than lines 1080 and they are more closely spaced. Each of the lines 1090 is composed of hundreds of dots.

[0077] By adding more diffraction grating sheets with different pattern densities to the path of the incident laser beam, it has been observed that more diffracted beams are generated to form dots. By passing the diffracted light through a lenticular sheet, as described, each dot is converted into a line, and each line is composed of hundreds or thousands of dots. An object that enters the paths of multiple beams is in the paths of thousands of laser beams and can be detected with good resolution using a lidar system. Additionally, a lidar system that utilizes thousands of laser beams in matrix form is sensitive even to small objects. The thousands of laser beams are densely spaced even at long distances, avoiding the need for a sweep similar to that performed using a laser cone. The limiting factors for the number of diffraction gratings used are the amount and intensity of the laser light to be passed through. A strong laser can further irradiate sufficient power to be used even with a large number of diffraction gratings, while a weak laser can only be used in combination with a few diffraction gratings. Application examples of the lidar system can specify the intensity of the laser used, and accordingly, the number of diffraction gratings, their pattern densities, as well as their angles relative to each other and to the lenticular lens. Additionally, the distance to the object to be detected can specify the number of gratings to be used. For example, for an object that is not too far away, a small number of gratings can be used because the resulting lines and dots are still densely spaced at close range. However, to detect a distant object, more gratings that generate more beams with a dense spacing using a lenticular sheet would be desirable. Since more gratings reduce the amount of transmitted laser light that affects the ability to detect an object using lidar, a stronger laser is required in that case.

[0078] Figure 21 illustrates a system for redirecting a laser beam by using two back-to-back linear lenticular sheets 150 and 450 with an offset interference pattern therebetween. As shown, the individual lenticular lenses of sheet 150 are horizontally offset laterally from those of sheet 450. An incident laser beam 120 directed towards lenticular sheet 450 is redirected as a turned beam 125 when it exits lenticular sheet 150. The interference pattern, therefore, displaces the laser beam. This is beneficial since laser designators are often used to mark targets in modern warfare. This is done for laser-guided bombs, missiles, and precision artillery munitions. By displacing the laser designator, there is a possibility that the weapon will miss the vulnerable point of a target, such as a tank, which often requires a direct hit at a specific location to disable.

[0079] Lasers are increasingly being used by ground forces to aim their weapons at the enemy. These lasers can operate at frequencies outside the visible spectrum and can be seen through night vision scopes or goggles. The materials used in Figure 21 function to redirect lasers not only in the visible spectrum but also in UV (ultraviolet), NIR (near infrared), and SWIR (shortwave infrared) and potentially those outside this range.

[0080] As a result of displacing the laser's pinpoint accuracy, soldiers may also fail to understand why they always miss the target and cannot hit it by aiming at the wrong location. Due to the disruptive elements of interference that conceal the target's situation, the enemy may not even realize that they have completely missed the target and may be considered to have hit it. This can cause the enemy to change their attack or defense posture or position, place the concealed target behind this material, easily find and identify the combatants, and target that adversary when they are most vulnerable to attack. With the system of Figure 21, when the laser beam is moved to the right, it deflects to the left, and vice versa. This is indicated by the arrows, showing that the deflected laser beam 125 moves in the opposite direction to the incident laser beam 120. An observer aiming at the target may notice that the projected laser dot on the target is moving in the direction opposite to the direction in which the laser source is being moved. Therefore, the observer may suspect that there is some form of camouflage material in front of the target and conclude that even if ammunition is fired towards the target using the observed dot, the target will not be accurately hit.

[0081] Figure 22 depicts an alternative arrangement of two back-to-back linear lenticular sheets 150 and 450. In this arrangement, the individual lenticular lenses of sheet 150 are angled horizontally with respect to those of sheet 450, creating an interference pattern that displaces the passing incident laser beam.

[0082] FIG. 23 illustrates a system for redirecting a laser beam by using two back-to-back linear lenticular sheets 150 and 450, and an additional double-sided lenticular sheet 170, with an offset interference pattern therebetween. As shown, the individual lenticular lenses of sheet 150 are offset horizontally from those of sheet 450. The double-sided lenticular sheet 170 is shown positioned between the laser source and the lenticular sheets 450 and 150, however, the lenticular sheet 170 may be positioned behind the lenticulars 150 and 450. The incident laser beam 120 directed towards the lenticular sheet 450 exits the lenticular sheet 150 as a redirected beam as in the case of FIG. 21, however, the redirected beam here passes through the double-sided lenticular sheet 170. In this case, the beam is redirected when the laser source is moved in a particular direction, and the redirected beam 125 moves in the same direction. Advantageously, the redirected beam does not project onto a set target, however, at the same time, when the laser source is moved, the projected laser dot appears to move in the same direction, so an observer may not suspect that the beam is being redirected. Thus, the observer may be under the impression that the target has been hit when ammunition is fired in the direction of the observed projected dot.

[0083] It will be apparent to those skilled in the art that lenticular sheets with lenticular lenses drawn to substantially the same dimensions, but different angles or different lines per inch (LPI), may be used interchangeably without affecting the way the present invention functions.

[0084] The lenticular sheets used in the illustrative embodiments consisted of longitudinally oriented lenticular sheets, however, other equivalent refractive reflective materials may be used. For example, prism lenses, double prism lenses, and double prism lenses split in the center may be used.

[0085] For all systems described herein that use a lenticular lens and / or a diffraction grating, the surface can be coated or manufactured with a protective element that can address some or all of the following, including but not limited to fog, water, fire, mud, dust, scratches, heat, cold, and ultraviolet radiation.

[0086] Although embodiments of the invention have been described merely as examples, it should be understood that the invention as defined by the appended claims is not limited to the specific details described in the above description of exemplary embodiments, and that many variations and substitutions are possible without departing from the scope of the claims.

Explanation of Reference Numerals

[0087] 20 Incident light beam 21 Light ray 22 Light ray 23 Light ray 24 Light ray 100 System 110 Laser source 120 Incident laser beam, incident laser light beam 125 Deflected light ray, deflected laser beam, deflected beam 126 Deflected light ray 127 Reflected light ray 128 Triangular plane 129 Triangular plane 130 Vertical line pattern, line 132 Small line 135 Horizontal line pattern, deflected light ray, refracted light ray, line 137 Reflected light ray 138 Curved surface 140 Arc pattern, arc 142 Small arc 150 Linear lenticular sheet 151 Lens side 152 Smooth side 155 Lenticular lens, lenticular element 160 Arc, refracted arc, sheet 162 Arc, reflected arc 165 Ellipse 167 dots 170 Double-sided lenticular sheet 175 Lenticular lens 180 Cone, laser cone 180a Arc, half laser cone 180b Arc, half laser cone 182 Circumferential dots 184 Line, perpendicular line, vertical direction 185 Line 200 System 210a Laser source 210b Laser source 220a Incident laser beam 220b Incident laser beam 250 Lenticular sheet 270 Laser cone 270a Reflection arc 270b Refraction arc 271 Dots 280 Laser cone 280a Reflection arc 280b Refraction arc 281 Dots 450 Linear lenticular sheet 1000 Linear (uniaxial) diffraction grating 1010 Line, horizontal line 1020 Vertical line 1024 Diffracted laser beam 1025 Dots 1080 Vertical line 1090 Oblique line 1500 Biaxial diffraction grating β Angle θ Horizontal incident angle, large angle

Claims

【Claim 1】 A system for deflecting a laser beam, the system comprising: a laser source that emits the laser beam; a lenticular sheet having a lens side including a plurality of parallel longitudinal lenticular lenses and a smooth side opposite the lens side; at least one diffraction grating having at least one biaxial diffraction grating oriented such that a first plurality of lines are oriented at a non-zero orientation angle with respect to a second plurality of lines; comprising; the at least one diffraction grating and the plurality of parallel longitudinal lenticular lenses are (a) the at least one diffraction grating is between the laser source and the lenticular sheet, whereby the laser beam first passes through the at least one diffraction grating, or (b) the lenticular sheet is between the laser source and the at least one diffraction grating, whereby the laser beam is positioned to first pass through the lenticular sheet, the laser source is directed toward the lens side of the lenticular sheet such that an incident laser beam is incident on the plurality of parallel longitudinal lenticular lenses from the lens side, a first portion of the incident laser beam is deflected by refraction by at least one of the plurality of parallel longitudinal lenticular lenses to form a refracted beam of a first shape, A second portion of the incident laser beam is reflected by at least one surface of the plurality of parallel longitudinal lenticular lenses to form a reflected beam of a second specific shape.

Images