Large-area scanning hologram camera system utilizing a combined light-gathering unit

Abstract

The present invention relates to a large-area scanning hologram camera system utilizing a combined light-gathering unit. According to the present invention, a large-area scanning hologram camera system is provided that includes: a scan beam generation unit which modulates the phase of a first beam split from a light source and converts it into a first curvature beam through a first beam curvature generation unit, converts the second beam into a second curvature beam through a second beam curvature generation unit, and then interferes the first and second curvature beams to form a scan beam; a scan unit which receives the scan beam as an injector and projects it onto an object, controlling the scanning position of the scan beam relative to the object in the horizontal and vertical directions and transmitting it to the object; a projection unit which includes a scan lens and an imaging lens system and projects the scan beam transmitted from the scan unit onto the object surface where the object is located; and a light-gathering unit which detects the beam after it has been reflected or fluoresced from the object and has passed through the imaging lens system again. According to the present invention, a large-area scanning hologram camera with high resolution can be realized.

Description

Technical Field

[0001] The present invention relates to a large-area scanning hologram camera system using a combined condenser, and more particularly, to a large-area scanning hologram camera system using a combined condenser capable of capturing a scanning hologram with high resolution over a large area.

Background Art

[0002] Conventional optical scanning hologram cameras form a beam pattern having a spatial distribution of a Fresnel zone plate using an interferometer, project the formed beam pattern onto an object through a scan mirror, and collect the beam reflected from the object to obtain a hologram of the object.

[0003] However, in such a conventional method, the size of the Fresnel zone plate must be smaller than the size of the reflecting surface of the scan mirror, and the imaging target area is determined by the scan angle range of the scan mirror and the distance to the object, making it difficult to capture a hologram with high resolution over a large area.

[0004] The technology that is the background of the present invention is disclosed in Patent Document 1.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The purpose of this invention is to provide a large-area scanning hologram camera system that utilizes a combined light-gathering unit, which can realize a high-resolution scanning hologram camera for a large area. [Means for solving the problem]

[0007] The present invention provides a large-area scanning hologram camera system comprising: a scan beam generation unit that modulates the phase of a first beam split from a light source and converts it into a first curvature beam through a first beam curvature generation unit, converts a second beam into a second curvature beam through a second beam curvature generation unit, and then interferes the first and second curvature beams to form a scan beam; a scan unit that receives the scan beam as an injector and projects it onto an object, and controls the scanning position of the scan beam relative to the object in the horizontal and vertical directions to transmit it to the object; a projection unit that includes a scan lens and an imaging lens system and projects the scan beam transmitted from the scan unit onto the object plane on which the object is located; and a focusing unit that detects the beam after it has been reflected or fluoresced from the object and has passed through the imaging lens system again.

[0008] Furthermore, the focusing unit may include an optical divider disposed between the scanning lens and the imaging lens system, which transmits the beam that has passed through the scanning lens to the imaging lens system and reflects the beam that has been reflected from the object and passed through the imaging lens system again; a focusing lens system into which the beam reflected by the optical divider is incident; and a photodetector for detecting the beam that has passed through the focusing lens system.

[0009] Furthermore, the imaging lens system can image the scan beam pattern that reaches the imaging surface of the imaging lens system onto the object surface where the object is located.

[0010] Furthermore, the scanning unit can transmit the scan beam, which has an optical axis that forms a slope with respect to the optical axis of the scan lens, to the field surface of the scan lens, by the scan angle of the x-scan unit and y-scan unit that control the scanning position in the horizontal and vertical directions.

[0011] Furthermore, if the field plane of the scan lens and the imaging plane of the imaging lens system are in the same position, the following formula can be satisfied.

[0012] JPEG2026522259000002.jpg1289

[0013] JPEG2026522259000003.jpg33166

[0014] Furthermore, if the field plane of the scan lens and the imaging plane of the imaging lens system are at different positions and separated by a set distance, the following formula can be satisfied.

[0015] JPEG2026522259000004.jpg11166

[0016] JPEG2026522259000005.jpg42166

[0017] Furthermore, the field size of the scanning lens's field plane is determined by the front focal length of the scanning lens and the scanning angle through the following formula.

[0018] JPEG2026522259000006.jpg14166

[0019] JPEG2026522259000007.jpg37166

[0020] Further, the projection unit may be disposed between the scanning lens and the imaging lens system, and may further include an optical axis conversion lens that aligns the centers of the optical axes of the scanning lens and the imaging lens system.

[0021] Further, the projection unit includes a first structure including a telecentric type scanning lens with a ray angle of 0° on the field plane, the optical axis conversion lens, and an imaging lens system with a chief ray angle of 0° or more on the imaging plane, a second structure including the telecentric type scanning lens, the optical axis conversion lens, and an imaging lens system with a chief ray angle of 0° or less on the imaging plane, a third structure including a scanning lens with a ray angle of 0° or more on the field plane, the optical axis conversion lens, and an imaging lens system with a chief ray angle of 0° or more on the imaging plane, a fourth structure including a scanning lens with a ray angle of 0° or more on the field plane, the optical axis conversion lens, and an imaging lens system with a chief ray angle of 0° or less on the imaging plane, a fifth structure including a scanning lens with a ray angle of 0° or less on the field plane, the optical axis conversion lens, and an imaging lens system with a chief ray angle of 0° or more on the imaging plane, and a sixth structure including a scanning lens with a ray angle of 0° or less on the field plane, the optical axis conversion lens, and an imaging lens system with a chief ray angle of 0° or less on the imaging plane, and may be embodied in a structure selected from these.

[0022] Further, when the positions of the field plane of the scanning lens and the object plane of the optical axis conversion lens are the same, the following formula can be satisfied.

[0023] JPEG2026522259000008.jpg1077

[0024] JPEG2026522259000009.jpg31166

[0025] Further, when the positions of the field plane of the scanning lens and the object plane of the optical axis conversion lens are different from each other and are separated by a set distance, the following formula can be satisfied.

[0026] JPEG2026522259000010.jpg11166

[0027] JPEG2026522259000011.jpg42166

[0028] Further, when the imaging surface of the optical axis conversion lens and the imaging surface of the imaging lens system are in the same position, the following formula can be satisfied.

[0029] JPEG2026522259000012.jpg1089

[0030] JPEG2026522259000013.jpg34166

[0031] Further, when the imaging surface of the optical axis conversion lens and the imaging surface of the imaging lens system are different from each other and are separated by a set distance, the following formula can be satisfied.

[0032] JPEG2026522259000014.jpg11166

[0033] JPEG2026522259000015.jpg41166

Advantages of the Invention

[0034] According to the present invention, a high-resolution scanning hologram camera for a large area can be realized.

Brief Description of the Drawings

[0035] [Figure 1] The drawing shows the configuration of a large-area scanning hologram camera system according to the first embodiment of the present invention. [Figure 2] The drawing more specifically explains the configuration of the projection unit shown in FIG. 1. [Figure 3]This is a drawing showing the configuration of a large-area scanning hologram camera system according to a second embodiment of the present invention. [Figure 4] This diagram provides a more detailed explanation of the configuration of the projection unit shown in Figure 3. [Figure 5] This is a diagram illustrating the ray angle of light rays in an optical system. [Modes for carrying out the invention]

[0036] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement them. However, the present invention can be embodied in various different forms and is not limited to the embodiments described herein. Furthermore, in order to clearly illustrate the present invention with reference to the drawings, parts that are not relevant to the description have been omitted, and similar parts throughout the specification are denoted by similar reference numerals.

[0037] Throughout the specification, when a part is described as being "connected" to another part, this includes not only cases where they are "directly connected," but also cases where they are "electrically connected" with other elements in between. Furthermore, when a part is described as "containing" a certain component, this means, unless otherwise stated, that it does not exclude other components, but rather that it may contain other components.

[0038] The present invention relates to a large-area scanning hologram camera system utilizing a combined light-gathering unit, and proposes a scanning hologram camera system having a structure in which a projection unit and a light-gathering unit are combined, thereby realizing a high-resolution scanning hologram camera for large areas.

[0039] The large-area scanning hologram camera system utilizing a combined light-gathering unit according to an embodiment of the present invention will be described in more detail below with reference to the drawings.

[0040] Figure 1 is a diagram showing the configuration of a large-area scanning hologram camera system according to a first embodiment of the present invention.

[0041] As shown in Figure 1, the large-area scanning hologram camera system 100 according to the first embodiment of the present invention includes a scan beam generation unit 110, a scanning unit 120, a projection unit 130, and a light-gathering unit 140. This basic structure is also applied in the second embodiment.

[0042] First, the scan beam generation unit 110 takes the first beam, which is divided from the light source, and converts it into a first curvature beam through the first lens 115 by frequency transitioning the first beam, and converts the second beam into a second curvature beam through the second lens 116. Then, it interferes the first and second curvature beams to form a scan beam.

[0043] The scan beam generation unit 110 uses the structure of a Mach-Zehnder interferometer, which divides the light source into a first and second beam to generate first and second curvature beams, and then recombines the two generated beams.

[0044] The scan beam generation unit 110 includes a first mirror (M1), an optical divider 111, a frequency transition means 112, second and third mirrors (M2, M3), first and second beam curvature generation units (N1, N2), and interference means 117, and may further include a light source.

[0045] The light source is the part that generates electromagnetic waves. Light sources can include a variety of means, such as laser generators capable of generating electromagnetic waves, LEDs (light-emitting diodes), and low-coherence beams like halogen light with short coherence lengths. Below, a representative example will be one where the light source is a laser generator.

[0046] The beam emitted from the light source is transmitted to the first mirror (M1), then reflected and input to the optical divider 111.

[0047] The optical splitter 111 separates the incident beam into a first beam and a second beam, transmits the first beam to the phase modulation means 112 (acoustic-optical modulator), and transmits the second beam to the third mirror (M3). In other words, the beam along the path of the first beam is transmitted to the phase modulation means 112 by the optical splitter 111, and the beam along the path of the second beam is transmitted to the third mirror (M3).

[0048] Here, the optical splitter 111 is composed of an optical fiber coupler, a beam splitter, a geometric phase lens, a diffraction optical element, etc., and can be implemented in a way that guides the beam through free space to transmit it to the outside. Here, if a means that can split the beam coaxially (in-line), such as a geometric phase lens, is used, the beam can be split coaxially into a first beam and a second beam. Below, we assume that each optical splitter is implemented as a beam splitter.

[0049] The phase modulation means 112 modulates the frequency of the first beam and then transmits it to the second mirror (M2). The frequency transition means, i.e., the phase modulation means, can use a frequency generated from a function generator (not shown) to shift the frequency of the first beam by about Ω and transmit it to the second mirror (M2). Here, the phase modulation means can be implemented as various modulators that modulate the phase of light using electrical signals, including acousto-optic modulators and electro-optic modulators.

[0050] The first beam reflected from the second mirror (M2) is transmitted to the first beam curvature generator (N1). The second beam reflected from the third mirror (M3) is transmitted to the second beam curvature generator (N2). The beam expander can be implemented as a collimator.

[0051] The first and second beam curvature generation units (N1 and N2) generate expanded beams having curvature between negative and positive curvature, which include the beams that have been incident on and collimated.

[0052] A specific example of the first beam curvature generation unit (N1) is a beam expander having a first lens 113 that converts the first beam reflected from a second mirror (M2) into a spherical wave, and a second lens 115 that generates a curved beam (first curvature beam) when the spherical wave is incident on it, and the curvature of the beam can be adjusted by adjusting the distance between the first lens 113 and the second lens 115. A specific example of the second beam curvature generation unit (N2) is a beam expander having a third lens 114 that converts the second beam reflected from a third mirror (M3) into a spherical wave, and a fourth lens 116 that generates a curved beam (second curvature beam) when the spherical wave is incident on it, and the curvature of the beam can be adjusted by adjusting the distance between the third lens 114 and the fourth lens 116.

[0053] The first beam curvature generation unit (N1) converts the first beam into a first curvature beam and transmits it to the interference means 117. That is, the first beam curvature generation unit (N1) modulates the spatial distribution of the first beam to generate a second curvature beam.

[0054] The second beam curvature generation unit (N2) converts the second beam into a first curvature beam and transmits it to the interference means 117. That is, the second beam curvature generation unit (N2) modulates the spatial distribution of the second beam to generate a second curvature beam.

[0055] The generated first and second curvature beams are transmitted to the scanning unit 130 after interfering with each other as they pass through the interference means 117. The interference means 117 can be implemented as a beam splitter.

[0056] The interference means 117 superimposes and interferes with the first beam (first curvature beam) that has passed through the first beam curvature generation unit (N1) and the second beam (second curvature beam) that has passed through the second beam curvature generation unit (N2) to form a scan beam having a Fresnel zone pattern interference pattern. Here, it is desirable to align the optical axes of the first curvature beam and the second curvature beam.

[0057] In this manner, the scan beam generation unit 110 converts the first beam and the second beam separated from the light source into first and second curvature beams, then superimposes them on each other through the interference means 117 to form a scan beam, and transmits the formed scan beam to the scan unit 120.

[0058] The beam incident on the scanning unit 120 can be transmitted to the projection unit 130 via the x-scanning unit (e.g., horizontal scan mirror) and the y-scanning unit (e.g., vertical scan mirror).

[0059] The scanning unit 120 may include a horizontal scan mirror 121 (hereinafter referred to as the x-scan mirror) and a vertical scan mirror 122 (hereinafter referred to as the y-scan mirror) to control the scanning position of the scan beam relative to an object in the horizontal and vertical directions. The scanning unit 120 uses these scan mirrors to control the incident scan beam in the horizontal (x-direction) and vertical (y-direction) directions and transmits it to the projection unit.

[0060] In embodiments of the present invention, the scanning unit 120 uses a mirror scanner. The mirror scanner is an xy scanner having an x-scan mirror 121 that scans an object (transparent object) in the x direction (left-right direction) about the y axis and a y-scan mirror 122 that scans an object (transparent object) in the y direction (up-down direction) about the x axis. Of course, in the present invention, the scanning unit is not limited to a mirror scanner, and similar means or other known scanning means can be used. For example, instead of the x-scan mirror and y-scan mirror, an x-spatial modulation scanner and a y-spatial modulation scanner can be substituted.

[0061] In this way, the scanning unit 120 controls the incident scan beam in the horizontal (x direction) and vertical (y direction) directions to form the optical axis of the superimposed beam of the first curvature beam and the second curvature beam at an angle to the optical axis of the scan lens 131 of the projection unit 130, and transmits it to the projection unit 130.

[0062] Here, the scanning unit 120 can transmit a scan beam having an optical axis inclined with respect to the optical axis of the scan lens 131 to the field plane of the scan lens 131 by the scan angles of the x-scan mirror and y-scan mirror, which control the scanning position in the horizontal and vertical directions.

[0063] The projection unit 130 includes a scan lens 131 and an imaging lens system 132 arranged sequentially between the scan unit 120 and the object. The projection unit 130 can project the scan beam transmitted from the scan unit 120 onto the object surface of the imaging lens system 132 where the object is located.

[0064] The projection unit 130 is implemented as a 4-f relay lens system afocally coupled between the x-scan mirror 121 and the y-scan mirror 122, allowing the rotation axes of the x-scan mirror 121 and the y-scan mirror 122 to be positioned at the entrance pupil of the scan lens. When the 4-f relay system is not used, it is desirable that the entrance pupil of the scan lens be positioned between the x-scan mirror and the y-scan mirror. Here, the rotation axis of the scan mirror is positioned at the entrance pupil of the scan lens, but it is desirable that it be positioned perpendicular to the optical axis of the scan lens.

[0065] The scan lens 131 can, by the angle of the scan mirror, form an inclination with respect to the optical axis of the scan lens 131, and the optical axis of the superimposed beam (scan beam) of the first and second curvature beams transmitted to the entrance pupil of the scan lens 131 can be positioned away from the optical axis of the scan lens 131 on the field plane of the scan lens 131. Here, the scan lens 131 can be embodied as a lens capable of performing the aforementioned role, such as an f-theta scan lens or a telecentric f-theta lens.

[0066] Figure 2 is a diagram that provides a more detailed explanation of the configuration of the projection unit shown in Figure 1.

[0067] As shown in Figure 2, the optical axis of the scan beam located in the field plane of the scan lens 131 can have a ray angle between -90° and 90° with respect to the optical axis of the scan lens 131.

[0068] JPEG2026522259000016.jpg24166

[0069] JPEG2026522259000017.jpg45166

[0070] JPEG2026522259000018.jpg28166

[0071] JPEG2026522259000019.jpg27166

[0072] The superimposed beam of the first curvature beam and the second curvature beam, i.e., the scan beam, is transmitted to the field plane of the scan lens 131 and then to the upper surface (image plane; hereinafter referred to as the imaging plane) of the imaging lens system 132. Here, it is desirable to position the optical axis of the scan lens 131 and the optical axis of the imaging lens system 132 to coincide. The imaging lens system 132 transmits the scan beam that has reached the imaging plane to the object plane of the imaging lens system 132. Here, an object is positioned in the region where the imaged scan beam was located.

[0073] JPEG2026522259000020.jpg27166

[0074] JPEG2026522259000021.jpg35166

[0075] JPEG2026522259000022.jpg36166

[0076] JPEG2026522259000023.jpg21166

[0077] In the first embodiment of the present invention, it is desirable that the ray angle of the optical axis of the scan beam transmitted to the imaging surface of the imaging lens system 132 from the field surface of the scan lens 131 coincides with the optical axis light of the principal ray of the imaging lens system 132.

[0078] As shown in Figure 2, when the field plane of the scan lens 131 and the imaging plane of the imaging lens system 132 are located at the same position, it is desirable that the following equation 1 be satisfied.

[0079] JPEG2026522259000024.jpg19166

[0080] JPEG2026522259000025.jpg31166

[0081] JPEG2026522259000026.jpg28166

[0082] When the position of the field plane of the scan lens 131 and the position of the imaging plane of the imaging lens system 132 are different, and the two planes are separated by a set distance, it is desirable that equation 2 be satisfied.

[0083] JPEG2026522259000027.jpg19166

[0084] JPEG2026522259000028.jpg49166

[0085] In this way, the imaging lens system 132 images the scan beam pattern that reaches the imaging surface of the imaging lens system 132 onto the object surface where the object is located.

[0086] Here, an object located on the object surface is scanned in such a way that the optical axis of the scan beam, which is imaged onto the object surface of the imaging lens system 132, moves to a position that is horizontally shifted (shifted) on the object surface by the scanning unit 120.

[0087] In this case, if the scan beam satisfies Equation 1 or Equation 2 between the field plane of the scan lens 131 and the imaging plane of the imaging lens system 132, the ray angle of the optical axis of the scan beam at the scan position where the scan beam reaches the object surface coincides with the ray angle of the principal ray of the imaging lens system 132 at that position, and distortion of the scan beam due to mismatch in ray angles is eliminated. In this case, it is desirable that the ray angle of the principal ray on the object surface of the imaging lens system 132 be 0° or greater in the direction of divergence along the optical axis in order to scan a Fresnel zone plate on an object that is the same size as or larger than the pupil size of the imaging lens system 132.

[0088] JPEG2026522259000029.jpg26166

[0089] JPEG2026522259000030.jpg17166

[0090] Here, the scan angle of the scan lens 131 represents the maximum scan half-angle. The field size of the scan lens 131 must be the same as, or smaller than, the field size of the imaging surface of the imaging lens system 132; it is preferable that they be the same. If the field size of the scan lens 131 is large, vignetting will occur in the imaging lens system 132, causing image distortion in the peripheral areas, and the field size plays an important role in resolving this.

[0091] The focusing unit 140 detects the beam after it has been reflected or fluoresced from the object to which the scan beam was irradiated, and then passed through the imaging lens system 132 again.

[0092] Such a light-gathering unit 140 may include a light-gathering optical system and a photodetector. The structure of the light-gathering unit 140 can have a variety of embodiments.

[0093] Specifically, the light-gathering unit 140 may include a second light splitter 141, a light-gathering lens system (light-gathering optical system) 142, and a photodetector 144, as shown in Figure 1.

[0094] The second optical splitter 141 is positioned between the scan lens 131 and the imaging lens system 132, and transmits the beam that has passed through the scan lens 131 to the imaging lens system 132, and reflects the beam that has been reflected from the object and passed through the imaging lens system 132 again to the focusing lens system 142.

[0095] In this process, the beam reflected or fluoresced from the object flows into the second optical splitter 141 through the imaging lens system 132, and this beam can be reflected again through the second optical splitter 141 and transmitted to the upper-end focusing lens system 142 and photodetector 144.

[0096] The second optical splitter 141 can be implemented as a polarization beam splitter or a non-polarization beam splitter. Additionally, a wave plate is added between the second optical splitter 141 and the image lens system 132.

[0097] The focusing lens system 142 can receive the beam reflected by the second optical splitter 141, focus the beam, and transmit it to the photodetector 144. Such a focusing lens system 142 can use a transmissive or reflective optical system and can be located at the same point as the optical axis of the image lens system 132. Here, the transmissive optical system consists of optical glass or plastic material that can transmit the wavelength of the laser light source and plays the role of refracting the light and focusing it to the photodetector 144. The reflective optical system has glass or metal material that is coated with a reflective coating so that the wavelength of the laser can be reflected, and can be embodied as an OFF-AXIS Parabolic Mirror, Spherical Mirror, Parabolic Mirror, etc. Furthermore, the focusing lens system 142 can also be embodied as a combination of a reflective optical system and a transmissive optical system.

[0098] Here, a bandpass filter (BPF) 143 is used between the focusing lens system 142 and the photodetector 144 to block light with a different wavelength from the laser light source used from entering the focusing unit 140.

[0099] The photodetector 144 detects the beam that has passed through the focusing lens system 142 and can be implemented as a photodiode, Avalanche photodiode, silicon photomultiplier, phototomultiplier tube, etc.

[0100] In this way, the light-gathering unit 140 images the beam reflected or fluoresced from the object through the imaging lens system 132 onto the detection surface of the photodetector 144 to form an image of the object, and spatially accumulates and focuses the luminosity of the image imaged onto the detection surface. It goes without saying that the detection surface may be located not only at the focal plane of the imaged image, but also at the defocused plane of the imaged image.

[0101] The light-gathering unit 140 can focus and detect the luminosity of an image on the detection surface of the photodetector 144 in a manner that generates an electrical signal proportional to the sum of the light.

[0102] In a scanning lens using a typical optical design methodology, the ray angle of the scan optical axis at the field plane of the scanning lens is equal to or greater than 0°, while the ray angle of the principal ray at the top plane of the imaging lens system is equal to or less than 0°.

[0103] Therefore, except in the case of a telecentric scan lens where the ray angle of the optical axis is 0° at the field plane of the scan lens and a telecentric imaging lens system where the ray angle of the principal ray is 0° at the top plane, when a commercially available scan lens and a commercially available imaging lens system designed by a general optical design methodology are combined to generate a projection unit, the mismatch between the scan optical axis of the scan lens and the optical axis of the principal ray of the imaging lens system results in distortion and scan field limitations on the object plane of the scan beam pattern, which is a superimposed beam of the first curvature beam and the second curvature beam.

[0104] To resolve this issue, the projection unit 230 of the second embodiment shown in Figure 3 has a structure in which an optical axis conversion lens 133 is further added between the scan lens 131 and the imaging lens system 132. The above configuration will be described below in six cases (Case 1, 2, 3, 4, 5, 6).

[0105] Figure 3 is a diagram showing the configuration of a large-area scanning hologram camera system according to a second embodiment of the present invention.

[0106] As shown in Figure 3, the large-area scanning hologram camera system 100 according to the second embodiment includes a scan beam generation unit 110, a scanning unit 120, a projection unit 230, and a light-gathering unit 140. Duplication of explanations for components having the same reference numerals as in Figure 1 is omitted.

[0107] As described above, in the second embodiment, the projection unit 230 has a structure that includes a scan lens 131, an optical axis conversion lens 133, and an imaging lens system 132. Here, the optical axis conversion lens 133 is positioned between the scan lens 131 and the imaging lens system 132 to align the centers of the optical axes of the scan lens 131 and the imaging lens system 132.

[0108] In this second embodiment, the scan lens 131 can be implemented as a telecentric type scan lens with a ray angle of 0° in the field plane, as a non-telecentric general scan lens with a ray angle of 0° or more in the field plane, or as a general scan lens with a ray angle of 0° or less in the field plane. Here, 0° or more means an angle greater than 0°, and less than 0° means an angle smaller than 0°.

[0109] Furthermore, the imaging lens system 132 can be realized as an imaging lens system in which the ray angle of the principal ray is 0° or greater on the imaging plane, or as an imaging lens system in which the ray angle of the principal ray is 0° or less on the imaging plane. Here, 0° or greater means an angle greater than 0°, and less than 0° means an angle smaller than 0°.

[0110] Here, the projection unit 230 is classified into a total of six types based on the concrete examples of the combination of the scan lens 131 and the imaging lens system 132 described above, as follows.

[0111] Case 1: Telecentric scan lens, optical axis conversion lens, and imaging lens system (first structure) in which the ray angle of the principal ray is 0° or greater during imaging.

[0112] Case 2: An imaging lens system (second structure) consisting of a telecentric scan lens, an optical axis conversion lens, and a principal ray ray angle of 0° or less on the imaging plane.

[0113] Case 3: A scanning lens, an optical axis conversion lens, and an imaging lens system (third structure) where the ray angle of the principal ray is 0° or greater on the field plane.

[0114] Case 4: A scanning lens, an optical axis conversion lens, and an imaging lens system (fourth structure) where the ray angle of the principal ray is 0° or less on the field plane.

[0115] Case 5: A scanning lens, an optical axis conversion lens, and an imaging lens system (fifth structure) where the ray angle of the principal ray is 0° or greater on the field plane.

[0116] Case 6: A scanning lens, an optical axis conversion lens, and an imaging lens system (sixth structure) where the ray angle of the principal ray is 0° or less on the field plane.

[0117] In other words, the projection unit 230 can be implemented using a structure selected from the first to sixth structures described above.

[0118] Figure 4 is a diagram that provides a more detailed explanation of the configuration of the projection unit shown in Figure 3.

[0119] As shown in Figure 4, the optical axis of the scan beam located in the field plane of the scan lens 131 can have a ray angle between -90° and 90° with respect to the optical axis of the scan lens 131.

[0120] JPEG2026522259000031.jpg27166

[0121] JPEG2026522259000032.jpg43166

[0122] JPEG2026522259000033.jpg28162

[0123] JPEG2026522259000034.jpg29166

[0124] In the structure of the second embodiment, the superimposed beam of the first curvature beam and the second curvature beam, i.e., the scan beam, is transmitted to the field plane of the scan lens 131 and then to the image plane of the optical axis conversion lens 133. Here, it is desirable to position the optical axis of the scan lens 131 and the optical axis of the optical axis conversion lens 133 so that they coincide.

[0125] JPEG2026522259000035.jpg22166

[0126] JPEG2026522259000036.jpg30166

[0127] JPEG2026522259000037.jpg31166

[0128] JPEG2026522259000038.jpg25166

[0129] In this second embodiment of the present invention, it is desirable that the ray angle of the optical axis of the scan beam transmitted to the object plane of the optical axis conversion lens 133 from the field plane of the scan lens 131 coincides with the optical axis light of the principal ray of the optical axis conversion lens 133.

[0130] As shown in Figure 4, when the field plane of the scan lens 131 and the object plane of the optical axis conversion lens 133 are located at the same position, it is desirable that the following equation 4 be satisfied.

[0131] JPEG2026522259000039.jpg15166

[0132] JPEG2026522259000040.jpg34166

[0133] JPEG2026522259000041.jpg38166

[0134] When the position of the field plane of the scan lens 131 and the position of the object plane of the optical axis conversion lens 133 are different, and the two planes are separated by a set distance, it is desirable that the following equation 5 be satisfied.

[0135] JPEG2026522259000042.jpg20166

[0136] Here, JPEG2026522259000043.jpg65 shows the distance between the field plane of the scan lens 131 and the object plane of the optical axis conversion lens 133.

[0137] JPEG2026522259000044.jpg46166

[0138] The scan beam that reaches the imaging plane of the optical axis conversion lens 133 is transmitted to the imaging plane of the imaging lens system 132. Here, it is desirable to position the optical axis of the scan lens 131 and the optical axis of the imaging lens system 132 to coincide.

[0139] The imaging lens system 132 images the scan beam that has reached the imaging surface and transmits it to the object surface of the imaging lens system 132. Here, the object is positioned in the region where the imaged scan beam was located.

[0140] JPEG2026522259000045.jpg28166

[0141] JPEG2026522259000046.jpg42166

[0142] JPEG2026522259000047.jpg34166

[0143] JPEG2026522259000048.jpg33166

[0144] In a second embodiment of the present invention, it is desirable that the ray angle of the optical axis of the scan beam transmitted to the imaging surface of the imaging lens system 132 from the field surface of the scan lens 131 coincides with the optical axis light of the principal ray of the imaging lens system 132.

[0145] As shown in Figure 4, when the imaging surface of the optical axis conversion lens 133 and the imaging surface of the imaging lens system 132 are located at the same position, it is desirable that the following equation 6 be satisfied.

[0146] JPEG2026522259000049.jpg20127

[0147] JPEG2026522259000050.jpg32166

[0148] JPEG2026522259000051.jpg29164

[0149] When the imaging surface of the optical axis conversion lens 133 and the imaging surface of the imaging lens system 132 are in different positions and the two surfaces are separated by a set distance, it is desirable that the following equation 7 be satisfied.

[0150] JPEG2026522259000052.jpg20166

[0151] JPEG2026522259000053.jpg55166

[0152] The imaging lens system 132 images the scan beam that has reached its imaging surface onto the object surface of the imaging lens system 132.

[0153] In this process, as equations 4 or 5 and 6 or 7 are satisfied, the ray angle of the optical axis of the scan beam at the scan position where the scan beam reaches the object surface coincides with the ray angle of the principal ray of the imaging lens system 132 at that position, thereby eliminating distortion of the scan beam due to the mismatch in ray angles. Similarly, it is desirable that the ray angle of the principal ray on the object surface of the imaging lens system 132 be 0° or greater in the direction of divergence along the optical axis for scanning a Fresnel zone plate on an object that is the same size as or larger than the pupil size of the imaging lens system 132.

[0154] Figure 5 is a diagram illustrating the ray angle of a light ray in an optical system. As shown in Figure 5, in the embodiments of the present invention, the ray angle refers to the angle of inclination of a guided light ray with respect to the optical axis, which has an inclination angle with respect to the optical axis of the optical system. Figure 5 illustrates the ray angle (θ1) of the incident beam and the ray angle (θ2) of the exit beam with respect to the lens system.

[0155] According to the present invention as described above, a high-resolution scanning hologram camera for large areas can be realized using a scanning hologram camera system in which a projection unit and a light-gathering unit are combined.

[0156] Although the present invention has been described with reference to the embodiments shown in the drawings, these are merely illustrative, and those skilled in the art will understand that a wider variety of modifications and equivalent other embodiments are possible. Therefore, the true scope of technical protection of the present invention must be determined by the technical idea of ​​the claims.

Claims

1. A scan beam generation unit modulates the phase of the first beam separated from the light source and converts it into a first curvature beam through a first beam curvature generation unit, converts the second beam into a second curvature beam through a second beam curvature generation unit, and then interferes the first and second curvature beams to form a scan beam. A scanning unit for receiving the scan beam and projecting it onto an object, and for controlling the scanning position of the scan beam relative to the object in the horizontal and vertical directions and transmitting it to the object, A projection unit that includes a scanning lens and an imaging lens system, and projects the scan beam transmitted from the scanning unit onto the object surface on which the object is located, A focusing unit for detecting the beam that has been reflected or fluoresced from the aforementioned object and then passed through the imaging lens system again, A large-area scanning hologram camera system, including [specific feature / feature].

2. The aforementioned light-gathering unit is An optical splitter is disposed between the scanning lens and the imaging lens system, which transmits the beam that has passed through the scanning lens to the imaging lens system, and reflects the beam that has been reflected from the object and passed through the imaging lens system again to the outside. A focusing lens system into which the beam reflected by the aforementioned optical splitter is incident, A photodetector that detects the beam that has passed through the aforementioned focusing lens system, The large-area scanning hologram camera system according to claim 1, including the following:

3. The aforementioned imaging lens system is The large-area scanning hologram camera system according to claim 1, wherein the scan beam pattern that has reached the imaging surface of the imaging lens system is imaged onto the surface of an object where the object is located.

4. The scanning unit is The large-area scanning hologram camera system according to claim 1, wherein the scan beam having an optical axis inclined with respect to the optical axis of the scan lens is transmitted to the field surface of the scan lens by the scan angle of the x-scan unit and y-scan unit that control the scanning position in the horizontal and vertical directions.

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8. The projection unit is, The large-area scanning hologram camera system according to claim 1, further comprising an optical axis conversion lens disposed between the scanning lens and the imaging lens system to align the optical axes of the scanning lens and the imaging lens system.

9. The projection unit is, A first structure comprising a telecentric type scan lens having a ray angle of 0° in the field plane, an optical axis conversion lens, and an imaging lens system having a ray angle of 0° or more for the principal ray in the imaging plane. A second structure comprising the telecentric type scan lens, the optical axis conversion lens, and an imaging lens system in which the ray angle of the principal ray is 0° or less on the imaging plane. A third structure comprising a scan lens having a ray angle of 0° or more on the field plane, the optical axis conversion lens, and an imaging lens system having a ray angle of 0° or more for the principal ray on the imaging plane. A fourth structure comprising a scan lens having a ray angle of 0° or more on the field plane, the optical axis conversion lens, and an imaging lens system having a ray angle of 0° or less on the imaging plane for the principal ray, A fifth structure comprising a scan lens with a ray angle of 0° or less on the field plane, the optical axis conversion lens, and an imaging lens system with a ray angle of 0° or more on the imaging plane for the principal ray, and The large-area scanning hologram camera system according to claim 8, which is embodied in a structure selected from a sixth structure including a scanning lens having a ray angle of 0° or less on the field plane, an optical axis conversion lens, and an imaging lens system having a ray angle of 0° or less on the imaging plane.

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