Imaging device, mobile terminal and image sensing method

Abstract

An imaging device, a mobile terminal and an image sensing method are provided. The imaging device comprises: a sensing array comprising a plurality of sensing elements; an imaging lens array comprising a plurality of imaging optical lenses, each of the plurality of imaging optical lenses having a non-circular cross-section perpendicular to an optical axis and configured to transmit light received from the outside of the imaging device; and a condenser lens array comprising a plurality of condenser lenses, the plurality of condenser lenses being arranged between the imaging lens array and the sensing array and configured to transmit light passing through the imaging lens array to the sensing elements, wherein the number of the plurality of imaging optical lenses is less than the number of the plurality of condenser lenses.

Description

[0001] This application claims the priority benefit of Korean Patent Application No. 10-2019-0174035 filed on December 24, 2019, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0002] Methods and apparatuses consistent with exemplary embodiments relate to technologies related to imaging devices. Background Art

[0003] Due to the development of optical technology and image processing technology, capture devices are used in a wide range of fields such as multimedia content, security and identification. For example, a capture device can be installed on a mobile device, a camera, a vehicle or a computer to capture an image, identify an object or obtain data for controlling the device. The volume of the capture device can be determined by the size of the lens, the focal length of the lens and the size of the sensor. In order to reduce the volume of the capture device, multiple lenses including small lenses can be used. Summary of the invention

[0004] One or more exemplary embodiments may address at least the above problems and / or disadvantages and other disadvantages not described above. In addition, exemplary embodiments are not required to overcome the disadvantages described above, and exemplary embodiments may not overcome any of the problems described above.

[0005] According to one aspect of an example embodiment, there is provided an imaging device, comprising: a sensing array including a plurality of sensing elements; an imaging lens array including a plurality of imaging optical lenses, each of the plurality of imaging optical lenses having a non-circular cross-section perpendicular to an optical axis and configured to transmit light received from outside the imaging device; and a condensing lens array including a plurality of condensing lenses, the plurality of condensing lenses being disposed between the imaging lens array and the sensing array and configured to transmit light passing through the imaging lens array to the sensing elements, wherein the number of the plurality of imaging optical lenses is less than the number of the plurality of condensing lenses.

[0006] The imaging device may also include an additional optical lens array, the additional optical lens including a plurality of additional optical lenses, each of the plurality of additional optical lenses having one of a circular cross-section and a non-circular cross-section perpendicular to the optical axis, and the additional optical lens array and the sensing array are respectively arranged on the back side of the imaging lens array.

[0007] The imaging lens array may be disposed closer to the condensing lens array than the additional optical lens array.

[0008] The imaging device may further include an aperture configured to transmit light, wherein the aperture and the sensing array are respectively disposed on opposite sides of the imaging optical array.

[0009] The sensing array may include a sensing area including some of the multiple sensing elements, the sensing area is configured to receive light from the multiple imaging optical lenses and is rectangular, and a cross-section of each of the multiple imaging optical lenses may correspond to a portion of a circular lens having a diameter greater than the length of a short side of the rectangular sensing area.

[0010] Each of the plurality of imaging optical lenses may correspond to a circular lens in which a portion of the circular lens having a diameter greater than a length of a short side of the rectangular sensing area is cut off.

[0011] Each of the plurality of imaging optical lenses may be configured to intersect a virtual straight line from an edge point of the aperture to a boundary of the sensing area.

[0012] In the peripheral portion of the multiple imaging optical lenses, a first refraction angle of a first light ray incident parallel to a virtual straight line from the center of each of the multiple imaging optical lenses to a boundary of the sensing area may be equal to a second refraction angle of a second light ray incident parallel to the main optical axis of each of the multiple imaging optical lenses.

[0013] A difference between a first optical path along which the first light ray reaches the sensing array and a second optical path along which the second light ray reaches the sensing array may be less than a threshold path difference.

[0014] The imaging device may further include: a processor configured to generate an image based on sensing information sensed by the sensing array.

[0015] According to another aspect of an example embodiment, an imaging device is provided, comprising: an imaging optical lens having a non-circular cross-section perpendicular to an optical axis, the imaging optical lens being configured to transmit light received from outside the imaging device; and a sensing array comprising a plurality of sensing elements, the sensing array being configured to sense light passing through the imaging optical lens through sensing elements among the plurality of sensing elements included in a sensing area, wherein the imaging optical lens and the sensing array are arranged in a fractional alignment structure.

[0016] The imaging device may further include: an additional optical lens having one of a circular cross section and a non-circular cross section perpendicular to the optical axis, the additional optical lens and the sensing array being respectively disposed on opposite sides of the imaging optical lens.

[0017] The imaging optical lens may be closer to the image sensor including the light-collecting microlenses and the sensing array than the additional optical lens.

[0018] The imaging device may further include: an aperture configured to transmit light, the aperture and the sensing array being respectively disposed on opposite sides of the imaging optical lens.

[0019] The sensing array may include a sensing area including some of the plurality of sensing elements, the sensing area being configured to receive light from an imaging optical lens and being rectangular, and a cross-section of the imaging optical lens may correspond to a portion of a circular lens having a diameter greater than a length of a short side of the rectangular sensing area.

[0020] The imaging optical lens may correspond to a circular lens in which a portion of the circular lens having a diameter greater than a length of a short side of the rectangular sensing area is cut off.

[0021] The portion is outside a sensing region corresponding to the imaging optical lens.

[0022] The non-circular cross-section of the imaging optical lens may include two arcs and two straight lines respectively connecting ends of the two arcs.

[0023] The non-circular cross-section of the imaging optical lens may include four arcs and four straight lines respectively connecting ends of the four arcs.

[0024] The non-circular cross-section of the imaging optical lens may correspond to a portion of a circle having a diameter greater than or equal to the diagonal length of the sensing region.

[0025] The non-circular cross-section of the imaging optical lens may be a quadrilateral.

[0026] The imaging optical lens may be configured to intersect a virtual line from an edge point of the aperture to a boundary of the sensing region.

[0027] In the peripheral portion of the imaging optical lens, a first refraction angle of a first light ray incident parallel to a virtual straight line from the center of the imaging optical lens to a boundary of the sensing area may be equal to a second refraction angle of a second light ray incident parallel to the optical axis of the imaging optical lens.

[0028] A difference between a first optical path along which the first light ray reaches the sensing array and a second optical path along which the second light ray reaches the sensing array may be less than a threshold path difference.

[0029] The ratio of the cross-sectional area of ​​the non-circular imaging optical lens to the area of ​​the sensing region may be greater than 0.78 and less than or equal to 1.

[0030] The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region may be greater than 0.58 and less than or equal to 1.

[0031] The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region may be greater than 0.44 and less than or equal to 1.

[0032] The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region may be greater than 0.39 and less than or equal to 1.

[0033] The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region may be greater than 0.89 and less than or equal to 1.

[0034] The imaging device may further include: a lens array including a plurality of non-circular imaging optical lenses.

[0035] The imaging device may further include: a processor configured to generate an image based on sensing information sensed by the sensing array.

[0036] The imaging device may further include: a lens array including an additional imaging optical lens having the same shape and the same size as the imaging optical lens, wherein the imaging optical lens and the additional imaging optical lens may be arranged along the same plane.

[0037] A fractional alignment structure may be a structure in which the sensing region includes a non-integer number of sensing elements.

[0038] According to another aspect of the example embodiment, an imaging device is provided, comprising: an imaging lens array including a plurality of non-circular imaging optical lenses, each of the plurality of non-circular imaging optical lenses being configured to transmit light received from outside the imaging device; and a sensing array including a plurality of sensing areas, each of the plurality of sensing areas being configured to sense light passing through the plurality of imaging optical lenses, the plurality of sensing areas each comprising a plurality of sensing elements.

[0039] Each of the plurality of sensing regions may include four or more sensing elements.

[0040] Each of the plurality of sensing regions may include nine or more sensing elements.

[0041] The imaging device may further include an aperture configured to transmit light, the aperture and the sensing array being respectively disposed on opposite sides of the imaging lens array.

[0042] The imaging device may further include: a filter disposed between the imaging lens array and the sensing array and configured to block light of a portion of wavelengths passing through the filter.

[0043] The imaging device may further include an additional optical lens having one of a circular cross section and a non-circular cross section perpendicular to the optical axis of the imaging device, the additional optical lens and the sensing array being respectively disposed on opposite sides of the imaging lens array.

[0044] The imaging device may further include a processor configured to generate an image based on sensing information sensed by the sensing array.

[0045] The ratio of the cross-sectional area of ​​the non-circular imaging optical lens to the area of ​​the sensing element may range from 0.78 to 1.0.

[0046] The imaging device may further include a condenser lens array including a plurality of condenser lenses disposed between the imaging lens array and the sensing array and configured to transmit light passing through the imaging lens array to the sensing array.

[0047] The number of the plurality of condensing lenses may be greater than the number of the plurality of non-circular imaging optical lenses.

[0048] According to one aspect of an example embodiment, there is provided a mobile terminal comprising: an image sensing component configured to receive external light through a non-circular imaging optical lens and generate sensing information based on sensing the external light through a plurality of sensing elements; a processor configured to reconstruct an output image based on the sensing information; and a memory configured to store at least one of the sensing information and the output image.

[0049] The image sensing assembly may further include: a plurality of condensing lenses disposed between the non-circular imaging optical lens and the plurality of sensing elements and configured to transmit light passing through the non-circular imaging optical lens to the plurality of sensing elements.

[0050] The non-circular imaging optical lens may be disposed closest to the plurality of condensing lenses.

[0051] The mobile terminal may also include a sensing area that may include a plurality of sensing elements, the sensing area being configured to receive light from a non-circular imaging optical lens and the sensing area being rectangular, and a cross-section of the non-circular imaging optical lens may correspond to a portion of a circle having a diameter greater than the length of a short side of the rectangular sensing area.

[0052] The non-circular imaging optical lens may correspond to a partially cut-off circular lens having a diameter greater than the length of a short side of the rectangular sensing area.

[0053] According to one aspect of an example embodiment, an imaging device is provided, the imaging device comprising: a sensing array comprising a plurality of sensing elements and a sensing area comprising a portion of the plurality of sensing elements; an imaging lens array comprising a plurality of imaging optical lenses, each of the plurality of imaging optical lenses having a non-circular cross-section perpendicular to an optical axis and configured to transmit light received from outside the imaging device; a condensing lens array comprising a plurality of condensing lenses, the plurality of condensing lenses being arranged between the imaging lens array and the sensing array and configured to transmit light passing through the imaging lens array to the sensing elements; an additional optical lens array comprising a plurality of additional optical lenses and being arranged on the imaging lens array opposite to the sensing array, wherein the non-circular cross-section in each of the plurality of imaging optical lenses corresponds to a circular lens whose diameter is greater than a portion of a length of a short side of a rectangular sensing area being cut off.

[0054] According to one aspect of an example embodiment, an image sensing method is provided, the image sensing method comprising: receiving, in a sensing area corresponding to an imaging optical lens in a sensing array, light passing through an imaging optical lens having a non-circular cross-section perpendicular to a main axis; and generating sensing information related to the sensing area by sensing the light passing through the imaging optical lens.

[0055] The receiving step may include: receiving a first light ray at a boundary of the sensing area, the first light ray being incident parallel to a virtual straight line from the center of the imaging optical lens to the boundary of the sensing area and being refracted at a first refraction angle by a peripheral portion of the imaging optical lens, and receiving a second light ray at the center of the sensing area, the second light ray being incident parallel to the optical axis of the imaging optical lens and being refracted at a second refraction angle similar to the first refraction angle by a peripheral portion of the imaging optical lens.

[0056] A difference between a first light path along which the first light reaches a boundary of the sensing region and a second light path along which the second light reaches a center of the sensing region may be less than a threshold path difference.

[0057] The step of receiving may include: receiving light rays passing through different imaging optical lenses by at least one sensing element in a sensing array.

[0058] The generating step may include: for sensing regions respectively corresponding to the plurality of imaging optical lenses, sensing intensity values ​​of light reaching sensing elements belonging to the corresponding sensing regions.

[0059] The image sensing method may further include reconstructing images respectively corresponding to the plurality of imaging optical lenses based on the sensed intensity values. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] The above and / or other aspects will become more apparent by describing exemplary embodiments with reference to the accompanying drawings, in which:

[0061] Figure 1A and Figure 1B shows a structure of an imaging device according to an exemplary embodiment;

[0062] Figure 2 shows a structure of an imaging device according to an exemplary embodiment;

[0063] Figure 3 illustrates an example of a shape of a lens included in an imaging device according to an exemplary embodiment;

[0064] Figure 4 A non-circular imaging optical lens included in an imaging device according to an exemplary embodiment is shown;

[0065] FIG. 5A to FIG. 5E shows an example of the shape of a non-circular imaging optical lens according to an exemplary embodiment;

[0066] Figure 6 illustrates the relationship between the vertical length of a non-circular imaging optical lens and the diagonal length of a sensing area according to an exemplary embodiment;

[0067] Figure 7 illustrates an optical path of an imaging device according to an exemplary embodiment;

[0068] Fig. 8A and Figure 8B shows a modulation transfer function (MTF) according to an exemplary embodiment;

[0069] Fig. 9 shows a lens array including non-circular lenses in an imaging device according to an exemplary embodiment;

[0070] Fig.10 illustrates an effective sensing area through a rectangular lens in an imaging device according to an exemplary embodiment;

[0071] Fig.11 shows a lens array including quadrilateral lenses in an imaging device according to an exemplary embodiment;

[0072] Fig.12 is a block diagram showing a configuration of an imaging device according to an exemplary embodiment;

[0073] Fig.13 A mobile terminal according to an exemplary embodiment is shown; and

[0074] Fig.14 is a flowchart illustrating an image sensing method according to an exemplary embodiment. DETAILED DESCRIPTION

[0075] Hereinafter, some exemplary embodiments will be described in detail with reference to the accompanying drawings. However, various changes and modifications may be made to the exemplary embodiments. Here, the exemplary embodiments are not to be interpreted as being limited to the disclosure, but should be understood to include all changes, equivalents and substitutes within the scope of the disclosed ideas and technologies.

[0076] The terms used herein are only for the purpose of describing specific exemplary embodiments, and will not limit exemplary embodiments. Unless the context clearly indicates otherwise, as used herein, the singular form is also intended to include the plural form. It will also be understood that the terms "comprising" and / or "including" when used herein, illustrate the existence of narrated features, wholes, steps, operations, elements and / or components, but do not exclude the existence or addition of one or more other features, wholes, steps, operations, elements, components and / or their groups. When a statement such as "at least one of" is after a column of elements, the entire column of elements is modified without modifying the individual elements in the column. For example, "at least one of a, b and c" should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b and c.

[0077] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the exemplary embodiments belong. It will also be understood that, unless expressly defined as such herein, terms (such as those defined in general dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and will not be interpreted in an idealized or overly formal sense.

[0078] When describing the exemplary embodiments with reference to the accompanying drawings, the same reference numerals represent the same constituent elements, and repeated descriptions related thereto will be omitted. In the description of the exemplary embodiments, when it is considered that a detailed description of a well-known related structure or function will lead to an obscure interpretation of the present disclosure, such description will be omitted.

[0079] Figure 1A and Figure 1B A structure of an imaging device according to an exemplary embodiment is shown. Figure 1A is a stereogram of the imaging device, and Figure 1B is a cross-sectional view of an imaging device.

[0080] Reference Figure 1A and Figure 1B , the imaging device 100 includes a lens array 110 and an image sensor 120. The lens array 110 includes lens elements, and the image sensor 120 includes sensing elements. The lens elements may be arranged along the plane of the lens array 110, and the sensing elements may be arranged along the plane of a sensing array 121 in the image sensor 120. The plane of the lens array 110 may be parallel to the plane of the sensing array 121. The lens array 110 may be a micro multi-lens array (MMLA) for imaging, and may also be an imaging lens array.

[0081] The image sensor 120 may include a sensing array 121, an optical filter 122, and a condensing lens array 123. According to an exemplary embodiment, when the image sensor 120 does not include the optical filter 122, the individual condensing microlenses 123a of the condensing lens array 123 may be configured to have optical characteristics of transmitting a predetermined wavelength band and blocking the remaining wavelength bands except the predetermined wavelength band.

[0082] The condenser lens array 123 may include a plurality of condenser micro lenses configured to condense light passing through the lens array 110 on the sensing array 121. For example, the number of condenser micro lenses included in the condenser lens array 123 may be equal to the number of sensing elements included in the sensing array 121. The plurality of condenser micro lenses may be disposed between the imaging optical lens and the sensing array 121 to transmit light passing through the imaging optical lens to the sensing element 121a corresponding to each condenser micro lens 123a by condensing the light on the sensing element 121a. For example, Figure 1B As shown in , the focusing microlens 123a may be disposed above each sensing element 121a of the sensing array 121 to focus light on the sensing element 121a disposed therebelow. Figure 1B As shown in FIG. 1 , the color filter 122 a may be disposed between each light-condensing microlens 123 a and each sensing element 121 a .

[0083] The optical filter 122 may be a filter having an optical property of transmitting a predetermined wavelength band and blocking the remaining wavelength bands. For example, the optical filter 122 may be implemented as a color filter array (CFA) including a plurality of color filters arranged along a filter plane. Each color filter 122a may be a filter that transmits light of a wavelength band corresponding to a predetermined color and blocks light of the remaining wavelength bands except the predetermined color. For example, the color filter 122a may include a red pass filter, a green pass filter, and a blue pass filter. The red pass filter may transmit light of a wavelength band corresponding to red, and block light of the remaining wavelength bands except the wavelength band corresponding to red. The green pass filter may transmit light of a wavelength band corresponding to green and block light of the remaining wavelength bands except the wavelength band corresponding to green. The blue pass filter may transmit light of a wavelength band corresponding to blue and block light of the remaining wavelength bands except the wavelength band corresponding to blue. In the CFA, the color filters that transmit color light respectively may be arranged in a Bayer pattern or another pattern. The optical filter 122 may also be an infrared cut filter that transmits the visible light band and blocks the infrared band.

[0084] The quality of the image captured and reconstructed by the image sensor 120 may be determined by the number of sensing elements included in the sensing array 121 and the intensity of light incident on the sensing element 121a. For example, the resolution of the image may be determined by the number of sensing elements included in the sensing array 121, the sensitivity of the image may be determined by the intensity of light incident on the sensing element 121a, and the intensity of the incident light may be determined by the size of the sensing element 121a. When the size of the sensing element 121a increases, the intensity of light may increase, and the dynamic range of the sensing array 121 may increase. Therefore, when the number of sensing elements included in the sensing array 121 increases, the image sensor 120 may capture a higher resolution image, and when the size of the sensing element 121a increases, the image sensor 120 may operate more advantageously when capturing a high-sensitivity image in a low-brightness environment.

[0085] The volume of the imaging device 100 may be determined by the focal length of the lens element 111. Specifically, the volume of the imaging device 100 may be determined by the spacing between the lens element 111 and the sensing array 121. This is because the image sensor 120 needs to be spaced apart from the lens element 111 by a distance corresponding to the focal length of the lens element 111 to collect light refracted by the lens element 111. Therefore, the plane of the lens array 110 may be spaced apart from the image sensor 120 by a distance corresponding to the focal length of the lens element 111 included in the lens array 110. The focal length of the lens element 111 is determined by the field of view (FoV) of the imaging device 100 and the size of the lens element 111. If the FoV is fixed, the focal length increases in proportion to the size of the lens element 111. In order to capture an image of a predetermined FoV range, the size of the lens element 111 needs to increase as the size of the sensing array 121 increases.

[0086] According to the above description, in order to increase the sensitivity of the image while maintaining the FoV and resolution of the image, the volume of the image sensor 120 increases. For example, in order to increase the sensitivity of the image while maintaining the resolution of the image, it is necessary to increase the size of each sensing element while maintaining the number of sensing elements included in the sensing array 121, and thus the size of the sensing array 121 increases. In this example, in order to maintain the FoV, as the size of the sensing array 121 increases, the size of the lens element 111 increases, and the focal length of the lens element 111 increases, and thus the volume of the image sensor 120 increases.

[0087] According to an exemplary embodiment, as the size of each lens element included in the lens array 110 is reduced (that is, as the number of lenses included in the same area on the lens array 110 is increased), the focal length of the lens element 111 can be reduced, and the thickness of the imaging device 100 can be reduced. Therefore, a relatively thin camera can be implemented. In this example, the imaging device 100 can reconstruct a high-resolution output image by rearranging and combining low-resolution images captured by each lens element 111.

[0088] A single lens element 111 of the lens array 110 may cover a predetermined sensing area 129 of the sensing array 121 corresponding to its lens size. In the sensing array 121, the sensing area 129 covered by the lens element 111 may be determined according to the lens size of the corresponding lens element 111. The sensing area 129 may be an area on the sensing array 121, and light of a predetermined FoV range may reach the sensing area 129 after passing through the lens element 111. The size of the sensing area 129 may be represented by a distance from the center to the outermost point of the sensing area 129 or a diagonal length. Light passing through the imaging optical lens may be received in the sensing area 129 corresponding to the imaging optical lens in the sensing array 121. That is, light passing through a single lens element 111 may be incident on a corresponding single sensing element of the sensing array 121 included in the sensing area 129.

[0089] Each of the sensing elements of the sensing array 121 may generate sensing information based on light passing through the lens of the lens array 110. For example, the sensing element 121a may sense an intensity value of light received through the lens element 111 as sensing information. The imaging device 100 may determine intensity information corresponding to an original signal related to a point included in the FoV of the imaging device 100 based on the sensing information output from the sensing array 121, and reconstruct a captured image based on the determined intensity information. For example, a single sensing element 121a of the sensing array 121 may be an optical sensing element configured using a complementary metal oxide semiconductor (CMOS) or a charge coupled device (CCD).

[0090] In addition, the sensing element 121a can generate a color intensity value corresponding to a desired color as sensing information by sensing light passing through the color filter 122a. Each of the plurality of sensing elements constituting the sensing array 121 can be configured to sense a color different from a color sensed by an adjacent sensing element spatially adjacent to the sensing element.

[0091] When the diversity of the sensing information is sufficiently ensured and a full rank relationship is formed between the original signal information corresponding to the point included in the FoV of the imaging device 100 and the sensing information, a captured image corresponding to the maximum resolution of the sensing array 121 can be obtained. The diversity of the sensing information can be ensured based on parameters of the imaging device 100, such as the number of lenses included in the lens array 110 and the number of sensing elements included in the sensing array 121.

[0092] In the multi-lens array structure for imaging, the imaging optical lens and the sensing array 121 may be arranged in a fractional alignment structure. For example, the fractional alignment structure may be a structure in which the sensing area 129 covered by a single lens element 111 includes a non-integer number of sensing elements. Each sensing area 129 of the sensing array 121 may include, for example, four or more sensing elements. In another example, each sensing area 129 may include nine or more sensing elements.

[0093] If the lens elements included in the lens array 110 have the same lens size, the number of lens elements included in the lens array 110 and the number of sensing elements included in the sensing array 121 may be relatively prime. A ratio P / L of the number of lens elements L corresponding to one axis of the lens array 110 and the number of sensing elements P corresponding to one axis of the sensing array 121 may be determined as a real number. The number of sensing elements covered by each of the lens elements may be equal to the number of pixel shifts corresponding to P / L. For example, Figure 1A The sensing area 129 may include 7 / 3=2.3 sensing elements along the horizontal axis and 11 / 3=3.67 sensing elements along the vertical axis. In addition, the lens element 111 may cover a plurality of (e.g., a non-integer number of) light-collecting microlenses 123a. Therefore, the number of light-collecting microlenses 123a in the image sensor 120 may be equal to the number of sensing elements 121a of the sensing array 121, and the number of lens elements 111 (e.g., imaging optical lenses) of the lens array 110 may be less than the number of light-collecting microlenses.

[0094] By using the fractional alignment structure as described above, the imaging device 100 can have a slightly different arrangement of the optical center axis (OCA) of each lens element 111 relative to the sensing array 121. That is, the lens element 111 can be eccentric relative to the sensing element 121a. For example, at least one sensing element of the sensing array 121 can receive light that passes through a different imaging optical lens. Figure 1B, the fourth sensing element from the left side may receive light passing through the lens element 111 on the left and the middle lens element. Therefore, each lens element 111 of the lens array 110 may receive different light field information. The light field (LF) may be emitted from a predetermined target point and may be a field indicating the direction and intensity of light reflected at a predetermined point on the subject. The light field information may be information combining multiple light fields. Since the direction of the main light of each lens element 111 also changes, each sensing area 129 receives different light field information. Therefore, the imaging device 100 may optically obtain more sensing information. For sensing areas corresponding to multiple imaging optical lenses, respectively, the image sensor 120 may sense the intensity values ​​of light reaching the sensing elements belonging to the corresponding sensing areas. The processor of the image sensor 120 may reconstruct images (e.g., multiple low-resolution images) corresponding to the multiple imaging optical lenses, respectively, based on the sensed intensity values. Therefore, the imaging device 100 may obtain multiple low-resolution input images through the various sensing information obtained as described above, and reconstruct a higher-resolution output image from the low-resolution input images.

[0095] Figure 2 A structure of an imaging device according to an exemplary embodiment is shown.

[0096] Reference Figure 2 , the imaging device 200 may include an imaging lens array 210 , a sensing array 220 , an additional lens array 230 , and an opening 240 . Figure 2 Only the sensing array 220 is shown, but example embodiments are not limited thereto, and Figure 1A and Figure 1B Other sensing elements may be included. For example, the filter 122 and the condenser lens array 123 may also be disposed between the sensing array 220 and the imaging lens array 210 .

[0097] The imaging lens array 210 may include optical lens elements for imaging. The lens element 211 may also be referred to as an imaging optical lens, and the f-number of the imaging device 200 may be set by the focal length f of the imaging optical lens 211. The imaging lens array 210, the imaging optical lens 211, the sensing array 220, and the sensing area 229 are respectively Figure 1A and Figure 1B The lens array 110, lens element 111, sensing array 121 and sensing area 129 are the same and / or similar.

[0098] The opening 240 may include a plurality of apertures. The aperture 241 may be, for example, circular in shape and transmit light. For example, the plurality of apertures may be formed along a plane corresponding to the opening 240. The plurality of apertures may be formed to have a circular cross-section perpendicular to the optical axis by being filled with a transparent material. However, exemplary embodiments are not limited thereto. Light passing through the plurality of apertures may be transmitted to a subsequent optical element corresponding to the aperture 241. Figure 2 In the embodiment, light passing through the aperture 241 of the opening 240 may be transmitted to the additional lens 231 of the additional lens array 230 .

[0099] The additional lens array 230 may include a plurality of additional lenses 231. The plurality of additional lenses 231 may be arranged along a virtual plane corresponding to the additional lens array 230. Each of the plurality of additional lenses 231 included in the additional lens array 230 may be configured to receive a light beam from a previous layer (e.g., Figure 2 The light received by the opening 240) is transmitted to the subsequent layer (e.g., Figure 2 Imaging lens array 210).

[0100] For reference, Figure 2 Each of the imaging lens array 210 and the additional lens array 230 is shown as a single layer. However, exemplary embodiments are not limited thereto. The imaging device 200 may also include a plurality of imaging lens arrays 210 and a plurality of additional lens arrays 230. Here, the imaging lens array 210 may be a lens array configured to ultimately form an image, and is disposed closer to the sensing array 220 than the additional lens array 230 among the lens arrays, and the imaging lens array 210 and the sensing array 220 may face each other. If the condenser lens array 123 of FIG. 1 is disposed on the sensing array 220, the condenser lens array 123 may be closest to the sensing array 220, and the imaging lens array 210 may be next (e.g., second) closest to the sensing array 220.

[0101] Here, the imaging lens array 210 and the additional lens array 230 may be referred to as an optical lens array. The imaging lens array 210 may be closer to the condenser lens array 123 than all other optical lens arrays. The area ratio of the non-circular imaging optical lens 211 to the corresponding sensing area 229 may be greater than the area ratio of the circular lens to the sensing area 229. Therefore, the optical power required for the light passing through the peripheral portion of the non-circular imaging optical lens 211 to reach the peripheral portion of the sensing area 229 may be reduced. That is, the optical error at the peripheral portion of the non-circular imaging optical lens 211 may be reduced.

[0102] Hereinafter, a description will be provided based on the optical elements through which a predetermined light ray passes on the optical path along which the light ray reaches the sensing array from the aperture 241. For example, the structure and arrangement of the aperture 241, the additional optical lens 231, the imaging optical lens 211, and the sensing area 229 will be described, and the description can also be similarly applied to the remaining optical elements of each array.

[0103] Figure 3 Illustrated are shapes of lenses included in an imaging device according to an exemplary embodiment.

[0104] Reference Figure 3 In the imaging device, the optical elements may be arranged in the order of an aperture 340, an additional optical lens 330, and an imaging optical lens 310. Figure 3 As shown in , a plurality of additional optical lenses 330 and a plurality of imaging optical lenses 310 may be provided.

[0105] The aperture 340 may transmit light. The aperture 340 and the sensing array 320 may be disposed on opposite sides relative to the imaging optical lens 310 .

[0106] The imaging optical lens 310 may have a non-circular cross-section perpendicular to the main axis of the imaging device, and transmits light received from the outside to the sensing array 320. The imaging optical lens 310 may have a non-circular cross-section to cover a larger sensing area. The imaging optical lens 310 may form an image on the plane of the sensing array 320 by refracting light received from an object. Figures 4 to 5E A cross section of the imaging optical lens 310 is described.

[0107] The additional optical lens 330 may have one of a circular cross-section and a non-circular cross-section perpendicular to the main axis, and may be arranged between the aperture 340 and the imaging optical lens 310, so that the additional optical lens 330 and the sensing array 320 may be arranged on the back side relative to the imaging optical lens 310. Figure 3 The additional optical lens 330 is shown to be a circular lens. However, exemplary embodiments are not limited thereto. For example, if there are a plurality of additional optical lenses 330, a portion of the plurality of additional optical lenses 330 may be circular lenses, and the rest of the plurality of additional optical lenses 330 may be non-circular lenses.

[0108] As described above, the sensing array 320 may include a plurality of sensing elements, and uses the sensing elements in the sensing area to sense the light passing through the imaging optical lens 310.

[0109] The imaging device may further include an optical filter 350. The optical filter 350 may be disposed between the imaging optical lens 310 and the sensing array 320 and filter out light of a portion of wavelengths passing through the imaging optical lens 310. For example, Figure 3 The optical filter 350 may be an infrared filter that blocks light having a wavelength in an infrared band and transmits light in a visible light band. Figure 3 The filter 350 may be different from Figure 1A and Figure 1B The filter 122 in the image sensor 120 is shown in FIG.

[0110] According to an exemplary embodiment, an additional imaging lens may not be provided between the imaging optical lens 310 and the image sensor including the sensing array 320. For example, if the imaging device includes a plurality of lenses such as the additional optical lens 330 and the imaging optical lens 310, the imaging optical lens 310 facing the sensing array 320 may be a lens closer to the sensing array 320 than the additional optical lens 330.

[0111] Figure 4 A non-circular imaging optical lens included in an imaging device according to an exemplary embodiment is illustrated.

[0112] exist Figure 4 , a front view of a single imaging optical lens 410 of the lens array and a sensing area 420 corresponding to the imaging optical lens 410 in the sensing array is shown.

[0113] The sensing area 420 may be rectangular. Figure 4 Shown are a length a of a short side of the rectangular sensing region 420, b length of a long side of the rectangular sensing region 420, h length from the center of the rectangular sensing region 420 to a vertex of the rectangular sensing region 420 (e.g., diagonal half length), and a diagonal length 2h of the sensing region 420. Each of a, b, h, and 2h may be expressed in a length unit (e.g., millimeter (mm), micrometer (μm), and nanometer (nm)).

[0114] The circular lens 401 configured to be smaller than the sensing area 420 covers only a portion of the sensing area 420, and thus light received from the outside may not reach the remaining portion of the sensing area 420 not covered by the circular lens 401. In addition, if the circular lens 401 is configured to transmit light to the remaining portion of the sensing area 420 not covered by the circular lens 401, optical aberration may occur due to excessive refraction at the peripheral portion of the circular lens 401.

[0115] The imaging optical lens 410 according to an exemplary embodiment may be a lens remaining after a portion of a circular lens 411 having a diameter greater than the length a of the short side of the rectangular sensing area 420 is cut off. For example, the imaging optical lens 410 may be a lens remaining after a portion 415 of a circular lens 411 having a diameter greater than the length a of the short side of the rectangular sensing area 420 is cut off, and the portion 415 is outside the sensing area 420 corresponding to the imaging optical lens 410. Therefore, the cross section of the imaging optical lens 410 may correspond to a portion of a circle having a diameter greater than the length a of the short side of the rectangular sensing area 420. Hereinafter, reference will be made to FIG. 5A to FIG. 5E Various shapes of the imaging optical lens 410 are described.

[0116] FIG. 5A to FIG. 5E An example of the shape of a non-circular imaging optical lens according to an exemplary embodiment is shown.

[0117] Here, the imaging optical lenses 511, 512, 513, 514, 515 can be as follows Figure 4 The lens left after the portion of the circular lens is cut off as described in the above description may be a non-circular lens. The cross-section of the imaging optical lenses 511, 512, 513, 514, 515 may be determined according to the shape of the sensing area 520. The diameter of the imaging optical lenses 511, 512, 513, 514, 515 may be the diameter of the circular lens before cutting off. The radius of the circular lens may be represented by Lh. The length from the center of the imaging optical lenses 511, 512, 513, 514, 515 to the long side of the sensing area 520 may be represented by Lh'.

[0118] Figure 5A An example is shown in which the diameter of the imaging optical lens 511 is longer than the length a of the short side of the sensing area 520 and shorter than the length b of the long side of the sensing area 520. The cross section of the imaging optical lens 511 may include two facing arcs 551 and 552 and straight lines 553 and 554 connecting the end of one arc to the end of the other arc, respectively. In the cross section, the first straight line 553 may connect the first end of the first arc 551 to the first end of the second arc 552. The second straight line 554 may connect the second end of the first arc 551 to the second end of the second arc 552.

[0119] Figure 5B An example is shown in which the diameter of the imaging optical lens 512 is longer than the length b of the long side of the sensing area 520 and shorter than the diagonal length 2h. Except for the upper and lower ends of the circular lens, both side portions of the circular lens are outside the sensing area 520 and can therefore be cut off. The imaging optical lens 512 may include four arcs 561, 563, 565, and 567 and straight lines 562, 564, 566, and 568 connecting the four arcs. The first arc 561 and the third arc 565 may face each other, and the second arc 563 and the fourth arc 567 may face each other. The first straight line 562 may connect the first arc 561 to the second arc 563. The second straight line 564 may connect the second arc 563 to the third arc 565. The third straight line 566 may connect the third arc 565 to the fourth arc 567. The fourth straight line 568 may connect the fourth arc 567 to the first arc 561. The first straight line 562 and the third straight line 566 may be parallel to each other, and the second straight line 564 and the fourth straight line 568 may be parallel to each other. The first straight line 562 and the third straight line 566 may be perpendicular to the second straight line 564 and the fourth straight line 568.

[0120] Figure 5CAn example is shown in which the diameter of the imaging optical lens 513 is greater than or equal to the diagonal length 2h of the sensing area 520. The cross section of the imaging optical lens 513 may correspond to a portion of a circle having a diameter greater than or equal to the diagonal length 2h of the sensing area 520. The cross section of the imaging optical lens 513 left after cutting off the portion of the circular lens may be a quadrilateral. In the cross section of the imaging optical lens 513, the first straight line 571 and the third straight line 573 may be parallel to each other, and the second straight line 572 and the fourth straight line 574 may be parallel to each other. In addition, the first straight line 571 and the third straight line 573 may be orthogonal to the second straight line 572 and the fourth straight line 574.

[0121] The non-circular optical lens may have a predetermined cross-sectional area greater than or equal to a predetermined cross-sectional area of ​​the sensing region 520 facing the non-circular optical lens. Figure 5C An example is shown in which the area ratio of the non-circular optical lens 513 to the sensing area 520 is 1 as a maximum value, Figure 5D An example is shown in which the area ratio of the non-circular optical lens 514 to the sensing area 520 is a minimum value.

[0122] Figure 5D Shown with less than Figure 5A The diameter of the non-circular imaging optical lens 511 before the minimum diameter of the lens 514 is equal to that of the circular optical lens 514. That is, the diameter of the non-circular imaging optical lens 511 needs to be larger than the diameter of the circular optical lens 514 (i.e., 2Lh>a), and the area ratio of the non-circular optical lens to the sensing area needs to exceed the ratio calculated based on the circular optical lens 514. Figure 5D In the example of FIG. 5 , the ratio of the cross-sectional area of ​​the optical lens to the area of ​​the sensing area 520 facing the optical lens (ie, the cross-sectional area S of the circular optical lens 514) is Lens,min and the area S of the sensing region 520 sensor The area ratio of ) can be expressed by Equation 1.

[0123] [Equation 1]

[0124]

[0125] According to Equation 1, if the ratio of the long side to the short side of the sensing area 520 is b:a=1:1, the minimum area ratio may be That is to say, according to FIG. 5A to FIG. 5D, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 511, 512, 513, 514 to the area of ​​the sensing area 520 may be greater than 0.78 and less than or equal to 1. However, the above area ratio may be changed according to the ratio of the long side to the short side of the sensing area 520. For example, if the ratio of the long side to the short side of the sensing area 520 is b:a=4:3, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 511, 512, 513, 514 to the area of ​​the sensing area 520 may be greater than 0.58 and less than or equal to 1. If the ratio of the long side to the short side of the sensing area 520 is b:a=16:9, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 511, 512, 513, 514 to the area of ​​the sensing area 520 may be greater than 0.44 and less than or equal to 1. If the ratio of the long side to the short side of the sensing area 520 is b:a=2:1, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 511, 512, 513, 514 to the area of ​​the sensing area 520 may be greater than 0.39 and less than or equal to 1. If the ratio of the long side to the short side of the sensing area 520 is b:a=4:1, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 511, 512, 513, 514 to the area of ​​the sensing area 520 may be greater than 0.19 and less than or equal to 1.

[0126] Figure 5E Shown in reference FIG. 5A to FIG. 5D The described structure is one in which the diameter 2Lh of the imaging optical lens 515 is the same as the length b of the long side of the sensing region 520 in the size range of the imaging optical lenses 511 , 512 , 513 , and 514 . Figure 5E The imaging optical lens 515 may cover all sensing elements on an axis (eg, a horizontal axis) passing through the center of the sensing region 520. Figure 5E In the structure, the area S of the imaging optical lens 515 is Lens,med and the area S of the sensing region 520 sensor The ratio can be expressed by Equation 2.

[0127] [Equation 2]

[0128]

[0129] According to Equation 2, if the ratio of the long side to the short side of the sensing area 520 is b:a=4:3, the ratio of the cross-sectional area of ​​the non-circular imaging optical lens 515 to the area of ​​the sensing area 520 may be approximately 0.8961. Figure 5E , Figure 5B and Figure 5CThe ratio of the cross-sectional area of ​​the imaging optical lenses 515, 512, 513 to the area of ​​the sensing area 520 may be greater than or equal to 0.89 and less than or equal to 1. Similarly, if the ratio of the long side to the short side of the sensing area 520 is b:a=16:9, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 515, 512, 513 to the area of ​​the sensing area 520 may be greater than or equal to 0.94 and less than or equal to 1. If the ratio of the long side to the short side of the sensing area 520 is b:a=2:1, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 515, 512, 513 to the area of ​​the sensing area 520 may be greater than or equal to 0.95 and less than or equal to 1. If the ratio of the long side to the short side of the sensing area 520 is b:a=4:1, the ratio of the cross-sectional area of ​​the non-circular imaging optical lenses 515, 512, 513 to the area of ​​the sensing area 520 may be greater than or equal to 0.98 and less than or equal to 1.

[0130] Figure 6 FIG. 1 shows a relationship between a vertical length of a non-circular imaging optical lens and a diagonal length of a sensing region according to an exemplary embodiment.

[0131] like Figure 6 As shown in , light passing through the aperture of the opening 640 may be incident on the sensing array via the additional optical lens 630 and the imaging optical lens 610. The imaging optical lens 610 may intersect with a virtual straight line 691 from an edge point of the aperture to a boundary of the sensing area 620. In the circular lens, a portion that does not intersect with the virtual straight line 691 may be cut off. A vertical length Lh' based on the optical axis 601 in the imaging optical lens 610 may be smaller than the radius Lh of the circular lens by a cut-off length Cut-h. For example, the vertical length Lh' of the imaging optical lens 610 may be smaller than a diagonal half length h based on the optical axis 601.

[0132] The cross section of the imaging optical lens 610 left after cutting away the portion of the circular lens may be as follows: FIG. 5A to FIG. 5C However, exemplary embodiments are not limited thereto.

[0133] The imaging optical lens 610 remaining after the portion of the circular lens is cut off by the cut-off length Cut-h as described above can be set not to overlap with another imaging optical lens corresponding to another sensing area in the sensing array. In addition, since the imaging optical lens 610 intersects the straight line path from the aperture to the boundary of the sensing area 620, optical aberrations and distortions can be minimized until the light passing through the aperture passes through the imaging optical lens 610 and reaches the sensing area 620.

[0134] For reference, Figure 6Only the vertical length Lh' of the non-circular imaging optical lens 610 and the diagonal half length h of the sensing area on the same 2D plane are shown to describe the length comparison, but the present invention is not limited thereto. The actual arrangement of the non-circular imaging optical lens 610 and the sensing array is not limited to Figure 6 For example, the imaging optical lens 610 and the sensing array may be as shown in FIG. Figure 4 Set up as shown in .

[0135] Figure 7 An optical path of an imaging device according to an exemplary embodiment is shown. Figure 7 It is a schematic top view of the imaging of the main light and the marginal light of the imaging optical lens 710.

[0136] The imaging optical lens 710 may be a portion of a circular lens having a diameter LD' that is left after cutting away the portion of the circular lens having a diameter LD'. FIG. 5A to FIG. 5C The lens may be of the shape shown in , and the diameter LD' of the circular lens may be the same or similar to the diagonal length SD' of the sensing area.

[0137] Here, at the peripheral portion 715 of the imaging optical lens 710, the first refraction angle θ′ of the first light ray 781 incident along a path parallel to a virtual straight line from the center of the imaging optical lens 710 to the boundary of the sensing area 720 may be similar to the second refraction angle Φ′ of the second light ray 782 incident parallel to the optical axis of the imaging optical lens 710. The peripheral portion 715 may include, for example, a point spaced apart from the center of the imaging optical lens 710 by a half length h of the diagonal of the sensing area 720 and its adjacent points. The first light ray 781 may be refracted by the peripheral portion 715 of the imaging optical lens 710 and reach the boundary of the sensing area 720. The second light ray 782 may be refracted by the same peripheral portion 715 and reach the center (e.g., focus) of the sensing area 720. The image sensor may receive the first light ray 781 at the boundary of the sensing area 720, the first light ray 781 being incident parallel to the virtual straight line from the center of the imaging optical lens 710 to the boundary of the sensing area 720 and being refracted by the peripheral portion of the imaging optical lens 710 at the first refraction angle θ′. In addition, the image sensor may receive a second light ray 782 at the center of the sensing area 720, the second light ray 782 being incident parallel to the optical axis of the imaging optical lens 710 and being refracted at a second refraction angle Φ′ by a peripheral portion of the imaging optical lens 710. As the difference between the first refraction angle θ′ and the second refraction angle Φ′ decreases, the imaging device may acquire an image of the subject with reduced optical aberration and distortion.

[0138] In addition, the difference between the first optical path along which the first light ray 781 reaches the sensing array and the second optical path along which the second light ray 782 reaches the sensing array may be less than the threshold path difference. That is, in the imaging optical lens, the difference in optical path length (OPD) between the light passing through the 0.0 field of the lens (e.g., light toward the center of the sensing area) and the light passing through the 1.0 field of the lens (e.g., light toward the boundary of the sensing area) may be reduced. As the difference in OPD decreases, optical aberrations and distortions may be reduced. For example, in a camera lens implemented on a smartphone, the maximum size of half the size of the lens in the 1.0 field and the 0.0 field may be 10 mm. In addition, the difference in OPD between the light passing through the 0.0 field and reaching the sensor and the light passing through the 1.0 field and reaching the sensor may be within 10 mm.

[0139] Fig. 8A and Figure 8B A modulation transfer function (MTF) according to an exemplary embodiment is shown.

[0140] Fig. 8A Show Figure 3 A side view of the structure of the imaging device and the MTF of the imaging device. Figure 8B Shows different from Figure 3 A side view of the structure of another imaging device including a circular lens 830 and the MTF of the device. MTF may be a type of indicator indicating optical performance. In MTF graphs 891 and 892, the vertical axis may indicate the MTF value, and the horizontal axis may indicate the spatial frequency. In MTF graphs 891 and 892, each line may indicate a transition in the MTF value of light incident on the aperture at a predetermined incident angle. The transition in the MTF value may be represented according to the spatial frequency. The incident angle may be an angle with respect to a perpendicular normal to the incident boundary surface.

[0141] exist Fig. 8A In the structure of the imaging device of FIG. 3 , light passing through the center and the boundary of the aperture of the opening 340 may pass through the additional optical lens 330 , the imaging optical lens 310 , and the filter 350 and reach the sensing area 320 . Figure 8B In the structure of the device, the light passing through the aperture of the opening 340 can pass through the circular lens 830 and the filter 350 and reach the sensing area 320. The light perpendicularly incident to the aperture can pass through Fig. 8A The imaging device has a structure in which the imaging optical lens 310 is located at the rear end of the central portion of the imaging optical lens 310 and can pass through Figure 8B As the incident angle formed by the aperture and the light increases, the light may pass through a portion farther from the central portion of the imaging optical lens 310 at the rear end (e.g., a peripheral portion) and a portion farther from the central portion of the circular lens 830 at the rear end (e.g., a peripheral portion).

[0142] Even for light that passes through the peripheral portion of the imaging optical lens 310 as light with a large incident angle, the MTF does not decrease significantly. Figure 8B In the MTF curve graph 892 of the device of FIG. 890 , the MTF value 899 of the light passing through the outer portion of the circular lens 830 as a light having a large incident angle relative to the aperture may be sharply attenuated as the spatial frequency increases. Fig. 8A The MTF curve diagram 891 of the imaging device may represent an MTF having a stable value for each incident angle of light and for each spatial frequency.

[0143] Fig. 9 A lens array including non-circular lenses in an imaging device according to an exemplary embodiment is illustrated.

[0144] The imaging device may include a lens array 900 in which a plurality of non-circular imaging optical lenses are arranged as an imaging array. For example, the lens array 900 may include an imaging optical lens 910 and an additional imaging optical lens arranged in the same shape and the same size as the imaging optical lens 910. The imaging optical lens 910 and the additional imaging optical lens may be arranged along the same plane. The sensing area 920 covered by the imaging optical lens 910 and the sensing area covered by the additional imaging optical lens may be the same in size and shape.

[0145] exist Fig. 9 , the size of the sensing array is shown to be M×N (mm) and the lens array 900 includes 2×2 imaging optical lenses. The sensing area occupied by each imaging optical lens 910 in the sensing array may be M / 2×N / 2 in size.

[0146] Fig.10 An effective sensing area through a quadrilateral lens in an imaging device according to an exemplary embodiment is illustrated.

[0147] Depending on the size of the lens in the sensing area of ​​the same size, different effective sensing areas may be available. For example, if circular imaging lenses 1001 are used in the lens array, the lenses cannot protrude outside the sensing area 1002 assigned to each circular imaging lens 1001. Therefore, the diameter of the circular imaging lens 1001 may be limited to the length of the short side of the sensing area or less. In this example, Fig.10 As shown in , the effective sensing area 1009 of the circular imaging lens 1001 can be limited to a portion of the sensing area 1002. For example, if the sensing array includes sensing elements that support a resolution of up to 108.6M (12032×9024), the resolution of the effective sensing area 1009 of the circular imaging lens 1001 can be limited to 81M.

[0148] On the contrary, if as shown in Figures 1 to Fig. 9When a non-circular imaging lens is used, the effective sensing area 1090 of the non-circular imaging lens 1010 may be substantially the same as or similar to the sensing area 1020, and thus the resolution of the effective sensing area 1090 may be approximately 108M. When the non-circular imaging lens 1010 is provided, the imaging device may use the entire area of ​​the sensing area 1020. Therefore, when compared to the circular imaging lens 1001, the imaging device including the non-circular imaging lens 1010 may capture an image with increased resolution for the same sensing area 1020.

[0149] Fig.10 A quadrilateral lens is shown as the non-circular imaging lens 1010, but exemplary embodiments are not limited thereto. The non-circular imaging lens 1010 may have a modified quadrilateral shape cross section in addition to a rectangular cross section and a square cross section.

[0150] Fig.11 A lens array including quadrilateral lenses in an imaging device according to an exemplary embodiment is illustrated.

[0151] In a lens array having lens elements arranged along a plane in a grid pattern, if the diameter LD' of each circular lens 1101 is greater than or equal to the diagonal length SD' of a single sensing area 1120, each circular lens 1101 may include an area overlapping with other circular lenses 1101. Since lenses cannot physically overlap, the non-circular imaging optical lens 1110 may be configured to be a shape remaining after cutting off a portion of the circular lens 1101 having a diameter LD' greater than or equal to the diagonal length SD' of the sensing area 1120. For example, a portion of the circular lens 1101 overlapping with other circular lenses 1101 may be cut off. Fig.11 As shown in , the non-circular imaging optical lens 1110 remaining after cutting off the portion of the circular lens 1101 having a diameter LD' greater than or equal to the diagonal length SD' of the sensing area 1120 may have a quadrilateral cross-section. For reference, although Fig.11 A lens array including non-circular imaging optical lenses 1110 is shown, each of which has a quadrilateral cross section of the same shape perpendicular to the optical axis, but exemplary embodiments are not limited thereto. The shape of at least one imaging lens may be different from the shapes of other imaging lenses in the lens array.

[0152] As described above, since the entire area of ​​each sensing region 1120 can be covered by the imaging optical lens having a quadrilateral cross section, the lens performance can be maximized and the optical aberration can be reduced. Therefore, the imaging device can acquire an image of the subject with a more improved resolution.

[0153] Fig.12 is a block diagram illustrating a configuration of an imaging device according to an exemplary embodiment. Fig.13A mobile terminal according to an exemplary embodiment is shown.

[0154] Reference Fig.12 , the imaging device 1200 may include an opening 1240, an additional optical lens 1230, an imaging optical lens 1210, a sensing array 1220, and a processor 1260. N additional optical lenses 1230 and N imaging optical lenses 1210 may be provided. Here, N may be an integer greater than or equal to 2. The additional optical lens 1230 may be provided as at least one layer, and the imaging optical lens 1210 may be provided as at least one layer. The sensing array 1220 may include a sensing element configured to generate an electrical signal by sensing light. The opening 1240, the additional optical lens 1230, the imaging optical lens 1210, and the sensing array 1220 are described above with reference to FIGS. 1 to 13 . Fig.12 The component including the imaging optical lens 1210 and the sensing array 1220 may be an image sensing component. In addition to the imaging optical lens 1210 and the sensing array 1220, the image sensing component may further include an opening 1240, an additional optical lens 1230, a filter 122 (such as Figure 1A and Figure 1B ) and the focusing lens array 123 (as shown in Figure 1A and Figure 1B ) or a combination of two or more of the opening 1240, the additional optical lens 1230, the filter 122 and the condenser lens array 123.

[0155] The processor 1260 may obtain information related to the subject through the opening 1240, the additional optical lens 1230, and the imaging optical lens 1210 and reconstruct an image of the subject. For example, the processor 1260 may generate an image based on the sensing information sensed by the sensing array 1220. The processor 1260 may acquire an image corresponding to a corresponding sensing area from the sensing information sensed in a single sensing area. The processor 1260 may acquire as many images as the sensing areas constituting the sensing array 1220. The processor 1260 may reconstruct a single high-resolution image by rearranging and / or reconfiguring the images generated based on the sensing information. However, the operation of the processor 1260 is not limited thereto.

[0156] The imaging device 1200 may be implemented as Fig.13 The mobile terminal 1300 is shown in FIG.

[0157] The image sensing component 1390 of the mobile terminal 1300 may be implemented in an ultra-thin structure by an imaging lens array 1394 including a non-circular imaging optical lens (e.g., a lens having a quadrilateral cross-section). The image sensing component 1390 may receive external light through the non-circular imaging optical lens and generate sensing information by sensing the external light using a plurality of sensing elements. For example, the image sensing component 1390 may include a sensing array 1391, a filter 1392, a condensing lens array 1393, an imaging lens array 1394, an additional lens array 1395, and an opening 1396. The elements of the image sensing component 1390 are as described above with reference to Fig.12 Therefore, the detailed description will be omitted for the sake of brevity.

[0158] The image sensing component 1390 may be implemented as a camera module for vision of a smart phone camera, a DSLR camera, or a vehicle / drone / CCTV recognition. For example, at least one of the rear camera 1311 and the front camera 1312 of the mobile terminal 1300 may be an image sensing component 1390. The rear camera 1311 may include a plurality of rear camera modules, and at least one of the plurality of rear camera modules may be an image sensing component 1390. In addition, the front camera 1312 may include one or more front camera modules, and at least one of the one or more front camera modules may be an image sensing component 1390.

[0159] The rear camera 1311 and the display 1340 may be provided on different sides (e.g., on opposite sides) in the housing of the mobile terminal 1300. The rear side may be a side opposite to the side on which the display 1340 is provided in the mobile terminal 1300. The front camera 1312 and the display 1340 may be provided on the same side in the housing of the mobile terminal 1300. The front side may be a side on which the display 1340 is provided in the mobile terminal 1300.

[0160] The image sensing component 1390 of the ultra-thin structure can transmit light to the sensing array 1391 through the imaging lens array 1394, and the processor 1320 of the mobile terminal 1300 can obtain the image of the subject through the sensing array 1391. The processor 1320 can reconstruct the output image based on the sensing information generated by the image sensing component 1390. For example, as shown in FIG. Fig.12 As described above, the processor 1320 may acquire as many images as the number of sensing regions constituting the sensing array 1391. The input image acquired for each sensing region may be a relatively low-resolution image. The processor 1320 may reconstruct a single high-resolution output image for the image sensing component 1390 by rearranging and / or reconfiguring the images generated based on the sensing information. For reference, although Fig.13A single processor 1320 is shown, but exemplary embodiments are not limited thereto. The mobile terminal 1300 may include a plurality of processors, and at least one processor 1320 among the plurality of processors may perform image processing with respect to sensing information sensed by the image sensing component 1390 .

[0161] The memory 1330 may store at least one of the sensing information and the output image. For example, the memory 1330 may temporarily or permanently store data required or calculated by the processor 1320 during a process of reconstructing a high-resolution output image from the sensing information.

[0162] Fig.14 is a flowchart illustrating an image sensing method according to an exemplary embodiment.

[0163] First, in operation 1410, an imaging device may transmit light received from the outside to a sensing array through an imaging optical lens having a non-circular cross-section perpendicular to a main axis of the imaging device.

[0164] In operation 1420 , the imaging device may sense light passing through the imaging optical lens using sensing elements in a sensing region of the sensing array.

[0165] However, the image sensing method is not limited to the above description, and may be the same as described above with reference to FIGS. 1 to 5. Fig.12 At least one of the described operations is performed simultaneously, in parallel and / or sequentially.

[0166] The units described herein can be implemented using hardware components, software components and / or their combinations. The processing device can be implemented using one or more general or special computers (such as, for example, a processor, a controller and an arithmetic logic unit (ALU), a digital signal processor (DSP), a microcomputer, a field programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor or any other device that can respond and execute instructions in a limited manner). The processing device can run an operating system (OS) and one or more software applications running on the OS. The processing device can also access, store, manipulate, process and create data in response to the execution of the software. For simple purposes, the description of the processing device is used as a singular, however, those skilled in the art will understand that the processing device may include multiple processing elements and multiple types of processing elements. For example, the processing device may include multiple processors or a processor and a controller. In addition, different processing configurations (such as parallel processors) are feasible.

[0167] Software may include computer programs, code segments, instructions, or some combination thereof, to independently or collectively instruct or configure a processing device to operate as desired. Software and data may be implemented permanently or temporarily in any type of machine, component, physical or virtual device, computer storage medium or device, or in a propagating signal wave capable of providing instructions or data to or interpreted by a processing device. Software may also be distributed on networked computer systems so that the software is stored and executed in a distributed manner. Software and data may be stored by one or more non-transitory computer-readable recording media.

[0168] The method according to the above exemplary embodiment may be recorded in a non-transitory computer-readable medium including program instructions to perform various operations of the above exemplary embodiments. The medium may also include program instructions, data files, data structures, etc., either individually or in combination. The program instructions recorded on the medium may be program instructions specially designed and constructed for the purpose of the exemplary embodiment, or they may be types known and available to technicians in the field of computer software. Examples of non-transitory computer-readable media include: magnetic media (such as hard disks, floppy disks, and tapes); optical media (such as CD-ROM disks, DVDs, and / or Blu-ray disks); magneto-optical media (such as optical disks); and hardware devices (such as read-only memory (ROM), random access memory (RAM), flash memory (e.g., USB flash drive, memory card, memory stick, etc.)) specially configured to store and execute program instructions. Examples of program instructions include both machine codes such as those generated by a compiler and files containing high-level codes that can be executed by a computer using an interpreter. The above-mentioned devices may be configured to act as one or more software modules to perform the operations of the above-mentioned exemplary embodiments, or vice versa.

[0169] Exemplary embodiments have been described above. However, it should be understood that various modifications may be made to these exemplary embodiments. For example, suitable results may be achieved if the described techniques are performed in a different order, and / or if the components in the described systems, architectures, devices, or circuits are combined in a different manner and / or replaced or supplemented by other components or their equivalents.

[0170] Although exemplary embodiments have been described with reference to the accompanying drawings, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the claims.

Claims

1. An imaging device, comprising: A sensing array including a plurality of sensing elements; an imaging lens array including a plurality of imaging optical lenses, each of the plurality of imaging optical lenses having a non-circular cross-section perpendicular to the optical axis and configured to transmit light received from outside the imaging device; as well as a condenser lens array, comprising a plurality of condenser lenses, the plurality of condenser lenses being disposed between the imaging lens array and the sensing array and configured to transmit light passing through the imaging lens array to the plurality of sensing elements, The number of the plurality of imaging optical lenses is less than the number of the plurality of focusing lenses. Wherein, in the outer portion of each of the plurality of imaging optical lenses, a first refraction angle of a first light ray incident parallel to a virtual straight line from the center of each of the plurality of imaging optical lenses to a boundary of a corresponding sensing area in the sensing array is equal to a second refraction angle of a second light ray incident parallel to an optical axis of each of the plurality of imaging optical lenses.

2. The imaging device according to claim 1, further comprising: The additional optical lens array comprises a plurality of additional optical lenses, each of which has one of a circular cross section and a non-circular cross section perpendicular to the optical axis. The additional optical lens array and the sensing array are respectively arranged on the opposite sides of the imaging lens array.

3. The imaging device according to claim 2, wherein: The imaging lens array is disposed closer to the condensing lens array than the additional optical lens array.

4. The imaging device according to claim 1, further comprising: The aperture is configured to transmit light, and the aperture and the sensing array are respectively arranged on the back-to-back sides of the imaging lens array.

5. The imaging device according to claim 1, wherein: The sensing array includes a sensing area including some of the plurality of sensing elements, the sensing area being configured to receive light from the plurality of imaging optical lenses and being a rectangular sensing area, and The cross section of each of the plurality of imaging optical lenses corresponds to a portion of a circular lens having a diameter greater than a length of a short side of the rectangular sensing area.

6. The imaging device according to claim 5, wherein: Each of the plurality of imaging optical lenses corresponds to a partially cut-off circular lens, wherein a diameter of the circular lens is greater than a length of a short side of the rectangular sensing area.

7. The imaging device according to claim 1, wherein: Each of the plurality of imaging optical lenses is configured to intersect a virtual straight line from an edge point of an aperture in the imaging device to a boundary of a sensing area.

8. The imaging device according to claim 1, wherein: A difference between a first optical path along which the first light reaches the sensing array and a second optical path along which the second light reaches the sensing array is less than a threshold path difference.

9. The imaging device according to claim 1, further comprising: A processor is configured to generate an image based on sensing information sensed by the sensing array.

10. An imaging device comprising: an imaging optical lens having a non-circular cross-section perpendicular to the optical axis, the imaging optical lens being configured to transmit light received from outside the imaging device; as well as a sensing array including a plurality of sensing elements, the sensing array being configured to sense light passing through the imaging optical lens through sensing elements included in the sensing region among the plurality of sensing elements, The imaging optical lens and the sensing array are arranged in a fractional alignment structure. Wherein, in the peripheral portion of the imaging optical lens, a first refraction angle of a first light ray incident parallel to a virtual straight line from the center of the imaging optical lens to a boundary of a corresponding sensing area in the sensing array is equal to a second refraction angle of a second light ray incident parallel to the optical axis of the imaging optical lens, The fractional alignment structure is a structure in which the sensing region includes a non-integer number of sensing elements.

11. The imaging device according to claim 10, further comprising: The additional optical lens has one of a circular cross section and a non-circular cross section perpendicular to the optical axis. The additional optical lens and the sensing array are respectively arranged on the opposite sides of the imaging optical lens.

12. The imaging device according to claim 11, wherein: The imaging optical lens is closer to the image sensor including the light-collecting microlens and the sensing array than the additional optical lens.

13. The imaging device according to claim 10, further comprising: The aperture is configured to transmit light, and the aperture and the sensing array are respectively arranged on opposite sides of the imaging optical lens.

14. The imaging device according to claim 10, wherein: The sensing area is configured to receive light from the imaging optical lens and is a rectangular sensing area, and Therein, the cross section of the imaging optical lens corresponds to a portion of a circular lens having a diameter greater than the length of a short side of the rectangular sensing area.

15. The imaging device according to claim 14, wherein: The imaging optical lens corresponds to a partially cut-off circular lens, wherein a diameter of the circular lens is greater than a length of a short side of the rectangular sensing area.

16. The imaging device according to claim 15, wherein: The portion is outside a rectangular sensing area corresponding to the imaging optical lens.

17. The imaging device according to claim 10, wherein: The non-circular cross-section of the imaging optical lens includes two arcs and two straight lines respectively connecting the ends of the two arcs.

18. The imaging device according to claim 10, wherein: The non-circular cross-section of the imaging optical lens includes four arcs and four straight lines respectively connecting ends of the four arcs.

19. The imaging device according to claim 10, wherein: The non-circular cross-section of the imaging optical lens corresponds to a portion of a circle having a diameter greater than or equal to the diagonal length of the sensing area.

20. The imaging device according to claim 19, wherein The non-circular cross-section of the imaging optical lens is a quadrilateral.

21. The imaging device according to claim 10, wherein: The imaging optical lens is configured to intersect a virtual straight line from an edge point of an aperture in the imaging device to a boundary of a sensing area.

22. The imaging device according to claim 10, wherein: A difference between a first optical path along which the first light reaches the sensing array and a second optical path along which the second light reaches the sensing array is less than a threshold path difference.

23. The imaging device according to claim 10, wherein: The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region is greater than 0.78 and less than or equal to 1.

24. The imaging device according to claim 10, wherein: The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region is greater than 0.58 and less than or equal to 1.

25. The imaging device according to claim 10, wherein: The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region is greater than 0.44 and less than or equal to 1.

26. The imaging device according to claim 10, wherein: The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region is greater than 0.39 and less than or equal to 1.

27. The imaging device according to claim 10, wherein: The ratio of the non-circular cross-sectional area of ​​the imaging optical lens to the area of ​​the sensing region is greater than 0.89 and less than or equal to 1.

28. The imaging device according to claim 10, wherein: The imaging optical lens includes a plurality of non-circular imaging optical lenses, and the plurality of non-circular imaging optical lenses are arranged in a lens array.

29. The imaging device according to claim 10, further comprising: A processor is configured to generate an image based on sensing information sensed by the sensing array.

30. The imaging device according to claim 10, further comprising: a lens array comprising an additional imaging optical lens having the same shape and the same size as the imaging optical lens, The imaging optical lens and the additional imaging optical lens are arranged along the same plane.

31. An imaging device comprising: an imaging lens array including a plurality of non-circular imaging optical lenses, each of the plurality of non-circular imaging optical lenses being configured to transmit light received from an exterior of the imaging device; as well as a sensing array comprising a plurality of sensing regions, each of the plurality of sensing regions being configured to sense light passing through the plurality of non-circular imaging optical lenses, the plurality of sensing regions each comprising a plurality of sensing elements, Wherein, in the outer portion of each of the multiple non-circular imaging optical lenses, a first refraction angle of a first light ray incident parallel to a virtual straight line from the center of each of the multiple non-circular imaging optical lenses to a boundary of a sensing area among the multiple sensing areas corresponding to each of the multiple non-circular imaging optical lenses is equal to a second refraction angle of a second light ray incident parallel to the optical axis of each of the multiple non-circular imaging optical lenses.

32. The imaging device according to claim 31, wherein Each of the plurality of sensing regions includes four or more sensing elements.

33. The imaging device according to claim 31, wherein Each of the plurality of sensing regions includes nine or more sensing elements.

34. The imaging device according to claim 31, further comprising: The aperture is configured to transmit light, and the aperture and the sensing array are respectively arranged on the back-to-back sides of the imaging lens array.

35. The imaging device according to claim 31, further comprising: The filter is disposed between the imaging lens array and the sensing array and is configured to block light of a portion of wavelengths passing through the filter.

36. The imaging device of claim 31 , further comprising: The additional optical lens has one of a circular cross section and a non-circular cross section perpendicular to the optical axis of the imaging device. The additional optical lens and the sensing array are respectively arranged on the opposite sides of the imaging lens array.

37. The imaging device according to claim 31, further comprising: A processor is configured to generate an image based on sensing information sensed by the sensing array.

38. The imaging device according to claim 31, wherein A ratio of a cross-sectional area of ​​a single non-circular imaging optical lens among the plurality of non-circular imaging optical lenses to an area of ​​a sensing element in a sensing region corresponding to the single non-circular imaging optical lens ranges from 0.78 to 1.

0.

39. The imaging device according to claim 31, further comprising: The condenser lens array includes a plurality of condenser lenses, which are disposed between the imaging lens array and the sensing array and are configured to transmit light passing through the imaging lens array to the sensing array.

40. The imaging device according to claim 39, wherein The number of the plurality of condensing lenses is greater than the number of the plurality of non-circular imaging optical lenses.

41. A mobile terminal, comprising: an image sensing component configured to receive external light through a non-circular imaging optical lens and generate sensing information based on sensing the external light through a plurality of sensing elements included in a sensing array; a processor configured to reconstruct an output image based on the sensed information; as well as a memory configured to store at least one of the sensing information and the output image, In which, in the outer portion of the non-circular imaging optical lens, a first refraction angle of a first light ray incident parallel to a virtual straight line from the center of the non-circular imaging optical lens to a boundary of a corresponding sensing area in the sensing array is equal to a second refraction angle of a second light ray incident parallel to the optical axis of the non-circular imaging optical lens.

42. The mobile terminal according to claim 41, wherein: Image sensing components include: A plurality of condensing lenses are disposed between the non-circular imaging optical lens and the plurality of sensing elements and are configured to transmit the light passing through the non-circular imaging optical lens to the plurality of sensing elements.

43. The mobile terminal according to claim 42, wherein: The non-circular imaging optical lens is disposed closest to the plurality of condensing lenses.

44. The mobile terminal according to claim 41, wherein: Some of the plurality of sensing elements are included in a sensing region, the sensing region is configured to receive light from a non-circular imaging optical lens and the sensing region is a rectangular sensing region, and Therein, the cross section of the non-circular imaging optical lens corresponds to a portion of a circle having a diameter greater than the length of a short side of the rectangular sensing area.

45. The mobile terminal according to claim 44, wherein: The non-circular imaging optical lens corresponds to a partially cut-off circular lens, wherein a diameter of the circular lens is greater than a length of a short side of the rectangular sensing area.

46. ​​An imaging device comprising: a sensing array comprising a plurality of sensing elements, wherein portions of the plurality of sensing elements are included in a rectangular sensing region; an imaging lens array including a plurality of imaging optical lenses, each of the plurality of imaging optical lenses having a non-circular cross-section perpendicular to the optical axis and configured to transmit light received from outside the imaging device; A condenser lens array, comprising a plurality of condenser lenses, the plurality of condenser lenses being disposed between the imaging lens array and the sensing array and configured to transmit light passing through the imaging lens array to the plurality of sensing elements; The additional optical lens array includes a plurality of additional optical lenses and is arranged on the imaging lens array opposite to the sensing array. wherein the non-circular cross-section in each of the plurality of imaging optical lenses corresponds to a partially cut-off circular lens, wherein a diameter of the circular lens is greater than a length of a short side of the rectangular sensing area, Wherein, in the outer portion of each of the plurality of imaging optical lenses, a first refraction angle of a first light ray incident parallel to a virtual straight line from the center of each of the plurality of imaging optical lenses to a boundary of a corresponding sensing area in the sensing array is equal to a second refraction angle of a second light ray incident parallel to an optical axis of each of the plurality of imaging optical lenses.

47. An image sensing method, comprising: receiving, in a sensing area corresponding to the imaging optical lens in the sensing array, light passing through the imaging optical lens having a non-circular cross section perpendicular to the main axis; as well as generating sensing information related to the sensing area by sensing light passing through the imaging optical lens, The receiving step includes: receiving a first light ray at the boundary of the sensing area, the first light ray is incident parallel to a virtual straight line from the center of the imaging optical lens to the boundary of the sensing area and is refracted at a first refraction angle by the outer portion of the imaging optical lens; and receiving a second light ray at the center of the sensing area, the second light ray is incident parallel to the optical axis of the imaging optical lens and is refracted at a second refraction angle similar to the first refraction angle by the outer portion of the imaging optical lens.

48. The image sensing method according to claim 47, wherein: A difference between a first light path along which the first light reaches a boundary of the sensing region and a second light path along which the second light reaches a center of the sensing region is less than a threshold path difference.

49. The image sensing method according to claim 47, wherein: The receiving steps include: Light passing through different imaging optical lenses is received by at least one sensing element in the sensing array.

50. The image sensing method according to claim 47, wherein: The generating step includes: for the sensing areas respectively corresponding to the plurality of imaging optical lenses, sensing the intensity values ​​of the light reaching the sensing elements belonging to the corresponding sensing areas.

51. The image sensing method according to claim 50, further comprising: Images respectively corresponding to the plurality of imaging optical lenses are reconstructed based on the sensed intensity values.

Images