Patent Description:
Due to the development of optical technology and image processing technology, capturing devices are utilized in a wide range of fields such as multimedia contents, security, and recognition. For example, a capturing device may be mounted on a mobile device, a camera, a vehicle, or a computer to capture an image, recognize an object, or obtain data for controlling the device. The volume of the capturing device may be determined by the size of a lens, the focal length of the lens, and the size of a sensor. To reduce the volume of the capturing device, multiple lenses including small lenses may be used. Document <CIT> is directed to a device, image processing device and method for optical imaging. An optical device for imaging comprises at least one microlens field having at least two microlenses and an image sensor having at least two image detector matrices. Each microlens forms together with an image detector matrix an optical channel. Document <CIT> describes a monolithic integration of plenoptic lenses on photosensor substrates. Usually, a microlens is placed for each photosensor. Under each plenoptic lens there are a predetermined number of pixels such as <NUM>. Document <CIT> is directed at a camera device, method of manufacturing a camera device, and a wafer scale package. A spacer substrate has through holes coaxially aligned with the optical axes through respective first lenses and second lenses. Document <CIT> describes a camera system and associated methods. An optics stack forms an imaging system and comprises two substrates. Each substrate has two surfaces that are parallel to each other and perpendicular to an optical axis of the imaging system.

The invention is described in the claims. The embodiments which do not fall within the scope of the claims are to be interpreted as examples useful for understanding the invention. The invention provides an imaging device according to claim <NUM>. The invention provides further an image sensing method according to claim <NUM>. One or more embodiments may address at least the above problems and/or disadvantages and other disadvantages not described above. Also, the embodiments are not required to overcome the disadvantages described above, and an embodiment may not overcome any of the problems described above.

According to an aspect of an embodiment, there is provided an imaging device including 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 an outside of the imaging device, and a condensing lens array including a plurality of condensing lenses disposed between the imaging lens array and the sensing array, and configured to transmit the light passing through the imaging lens array to the sensing elements, wherein a number of the plurality of imaging optical lenses is less than a number of the plurality of condensing lenses.

The imaging device may further include an additional optical lens array 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, the additional optical lens array and the sensing array being respectively disposed on opposite sides of the imaging lens array.

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

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

The sensing array may include a sensing region that includes a portion of the sensing elements of the plurality of sensing elements, the sensing region being configured to receive the light from the plurality of imaging optical lenses and being rectangular, and the cross-section of each of the plurality of imaging optical lenses may correspond to a portion of a circular lens having a diameter greater than a length of a short side of the rectangular sensing region.

Each of the plurality of imaging optical lenses may correspond to the circular lens with a portion where the diameter of the circular lens is greater than the length of the short side of the rectangular sensing region is cut off.

Each of the plurality of imaging optical lenses may be configured to intersect with virtual straight lines from edge points of an aperture to a boundary of a sensing region.

At an outer portion of each of the plurality of imaging optical lenses, a first refraction angle of a first ray incident parallel with a virtual straight line from a center of each of the plurality of imaging optical lenses to a boundary of a sensing region may be equal to a second refraction angle of a second ray incident parallel with the principle optical axis of each of the plurality of imaging optical lenses.

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

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

According to another aspect of an embodiment, there is provided an imaging device including an imaging optical lens having a non-circular cross-section perpendicular to an optical axis, the imaging optical lens configured to transmit light received from an outside of the imaging device, and a sensing array including a plurality of sensing elements, the sensing array configured to sense the light passing through the imaging optical lens through a sensing element among the plurality of sensing elements included in a sensing region, wherein the imaging optical lens and the sensing array are disposed in a fractional alignment structure.

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 respectively being disposed on opposite sides of the imaging optical lens.

The imaging optical lens may be closer to an image sensor including a condensing microlens and the sensing array than the additional optical lens.

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

The sensing array may include a sensing region that includes a portion of the sensing elements of the plurality of sensing elements, the sensing region being configured to receive the light from the imaging optical lens and being rectangular, and the cross-section of the imaging optical lens may correspond to a portion of a circular lens with a diameter greater than a length of a short side of the rectangular sensing region.

The imaging optical lens may correspond to the circular lens with a portion where the diameter of circular lens is greater than the length of the short side of the rectangular sensing region is cut off.

The portion may be outside of the rectangular sensing region corresponding to the imaging optical lens.

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.

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.

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

The non-circular cross-section of the imaging optical lens may be quadrangular.

The imaging optical lens may be configured to intersect with virtual lines from edge points of an aperture to a boundary of the sensing region.

At an outer portion of the imaging optical lens, a first refraction angle of a first ray incident parallel with a virtual straight line from a center of the imaging optical lens to a boundary of the sensing region may be equal to a second refraction angle of a second ray incident parallel with the optical axis of the imaging optical lens.

A proportion of a cross-sectional area of the non-circular imaging optical lens to an area of the sensing region may be greater than <NUM> and less than or equal to <NUM>.

A proportion of the non-circular cross-sectional area of the imaging optical lens to an area of the sensing region may be greater than <NUM> and less than or equal to <NUM>.

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

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

The fractional alignment structure may be a structure in which the sensing region includes a non-integer number of sensing elements.

According to another aspect of an embodiment, there is provided an imaging device including 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 outside of the imaging device, and a sensing array including a plurality of sensing regions, each of the plurality of sensing regions configured to sense the light passing through the plurality of imaging optical lenses, the plurality of sensing regions each including a plurality of sensing elements.

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

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

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

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

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.

A proportion of a cross-sectional area of the non-circular imaging optical lens to an area of the sensing elements may range from <NUM> to <NUM>.

The imaging device may further include a condensing lens array including a plurality of condensing lenses disposed between the imaging lens array and the sensing array, and may be configured to transmit the light passing through the imaging lens array to the sensing array.

A number of the plurality of condensing lenses may be greater than a number of the plurality of non-circular imaging optical lenses.

According to an aspect of an embodiment, there is provided a mobile terminal including an image sensing assembly 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.

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 the light passing through the non-circular imaging optical lens to the plurality of sensing elements.

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

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

The non-circular imaging optical lens may correspond to a portion of a circular lens with the diameter greater than the length of the short side of the rectangular sensing region being cut off.

According to an aspect of an embodiment, there is provided an imaging device including a sensing array including a plurality of sensing elements and a sensing region including a portion of the 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 an outside of the imaging device, a condensing lens array including a plurality of condensing lenses disposed between the imaging lens array and the sensing array, and configured to transmit the light passing through the imaging lens array to the sensing elements, an additional optical lens array including a plurality of additional optical lenses and disposed on the imaging lens array opposite to the sensing array, wherein the non-circular cross-section of each of the plurality of imaging optical lenses corresponds to a circular lens with a portion where a diameter of the circular lens is greater than a length of a short side of the rectangular sensing region being cut off.

According to an aspect of an embodiment, there is provided an image sensing method including receiving light passing through an imaging optical lens having a non-circular cross-section perpendicular to a principal axis in a sensing area corresponding to the imaging optical lens in a sensing array, and generating sensing information related to the sensing region by sensing the light passing through the imaging optical lens.

The receiving may include receiving a first ray at a boundary of the sensing region, the first ray incident parallel with a virtual straight line from a center of the imaging optical lens to the boundary of the sensing region and refracted by an outer portion of the imaging optical lens at a first refraction angle, and receiving a second ray at a center of the sensing region, the second ray incident parallel with an optical axis of the imaging optical lens and refracted by the outer portion of the imaging optical lens at a second refraction angle which is similar to the first refraction angle.

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

The receiving may include receiving rays passing through different imaging optical lenses by at least one sensing element of the sensing array.

The generating may include, for sensing regions respectively corresponding to a plurality of imaging optical lenses, sensing intensity values of light reaching sensing elements belonging to the corresponding sensing regions.

The image sensing method may further include reconstructing images respectively corresponding to the plurality of imaging optical lenses based on the sensed intensity values.

The above and/or other aspects will be more apparent by describing embodiments with reference to the accompanying drawings, in which:.

Hereinafter, some embodiments will be described in detail with reference to the accompanying drawings. However, various alterations and modifications may be made to the embodiments.

The terminology used herein is for the purpose of describing particular embodiments only and is not to be limiting of the embodiments.

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

When describing the embodiments with reference to the accompanying drawings, like reference numerals refer to like constituent elements and a repeated description related thereto will be omitted. In the description of embodiments, detailed description of well-known related structures or functions will be omitted when it is deemed that such description will cause ambiguous interpretation of the present disclosure.

<FIG> illustrate a structure of an imaging device according to an embodiment. <FIG> is a perspective view of the imaging device, and <FIG> is a cross-sectional view of the imaging device.

Referring to <FIG>, an imaging device <NUM> includes a lens array <NUM> and an image sensor <NUM>. The lens array <NUM> includes lens elements, and the image sensor <NUM> includes sensing elements. The lens elements may be disposed along a plane of the lens array <NUM>, and the sensing elements may be disposed along a plane of a sensing array <NUM> in the image sensor <NUM>. The plane of the lens array <NUM> may be parallel with the plane of the sensing array <NUM>. The lens array <NUM> may be a micro multi-lens array (MMLA) for imaging and also be an imaging lens array.

The image sensor <NUM> may include the sensing array <NUM>, an optical filter <NUM>, and a condensing lens array <NUM>. According to an embodiment, when the image sensor <NUM> does not include the optical filter <NUM>, an individual condensing microlens 123a of the condensing lens array <NUM> may be configured to have an optical characteristic of transmitting a predetermined wavelength band and blocking the remaining wavelength bands other than the predetermined wavelength band.

The condensing lens array <NUM> may include a plurality of condensing microlenses configured to concentrate light passing through the lens array <NUM> on the sensing array <NUM>. For example, the number of condensing microlenses included in the condensing lens array <NUM> may be equal to the number of sensing elements included in the sensing array <NUM>. The plurality of condensing microlenses may be disposed between imaging optical lenses and the sensing array <NUM> to transmit light passing through the imaging optical lenses to the sensing elements 121a corresponding to the respective condensing microlenses 123a by concentrating the light on the sensing elements 121a. For example, as shown in <FIG>, a condensing microlens 123a may be disposed above each sensing element 121a of the sensing array <NUM> to concentrate light on the sensing element 121a disposed thereunder. Further, as shown in <FIG>, a color filter 122a may be disposed between each condensing microlens 123a and each sensing element 121a.

The optical filter <NUM> may be a filter having an optical characteristic of transmitting a predetermined wavelength band and blocking the remaining wavelength bands. For example, the optical filter <NUM> may be implemented as a color filter array (CFA) including a plurality of color filters disposed 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 other than 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 blocks light of the remaining wavelength bands other than the wavelength band corresponding to red. The green-pass filter may transmit light of a wavelength band corresponding to green and blocks light of the remaining wavelength bands other than the wavelength band corresponding to green. The blue-pass filter may transmit light of a wavelength band corresponding to blue and blocks light of the remaining wavelength bands other than the wavelength band corresponding to blue. In the CFA, the color filters that respectively transmit color lights may be disposed in a Bayer pattern or another pattern. The optical filter <NUM> may also be an infrared cut-off filter that transmits a visible light band and blocks an infrared band.

The quality of an image captured and reconstructed by the image sensor <NUM> may be determined by the number of sensing elements included in the sensing array <NUM> and an intensity of light incident to the sensing elements 121a. For example, the resolution of an image may be determined by the number of sensing elements included in the sensing array <NUM>, the sensitivity of the image may be determined by the intensity of light incident on the sensing elements 121a, and the intensity of incident light may be determined by the size of the sensing elements 121a. As the size of the sensing elements 121a increases, the intensity of light may increase, and the dynamic range of the sensing array <NUM> may increase. Thus, as the number of sensing elements included in the sensing array <NUM> increases, the image sensor <NUM> may capture a higher-resolution image, and as the size of the sensing elements 121a increases, the image sensor <NUM> may operate more advantageously in capturing a high-sensitivity image in a low luminance environment.

The volume of the imaging device <NUM> may be determined by a focal length of a lens element <NUM>. In detail, the volume of the imaging device <NUM> may be determined by a gap between the lens element <NUM> and the sensing array <NUM>. That is because the image sensor <NUM> needs to be spaced apart from the lens element <NUM> by a distance corresponding to the focal length of the lens element <NUM> to collect light refracted by the lens element <NUM>. Thus, the plane of the lens array <NUM> may be spaced apart from the image sensor <NUM> by the distance corresponding to the focal length of the lens element <NUM> included in the lens array <NUM>. The focal length of the lens element <NUM> is determined by a field of view (FoV) of the imaging device <NUM> and the size of the lens element <NUM>. If the FoV is fixed, the focal length increases in proportion to the size of the lens element <NUM>. To capture an image of a predetermined range of FoV, the size of the lens element <NUM> needs to be increased as the size of the sensing array <NUM> increases.

According to the above description, in order to increase the sensitivity of an image while maintaining the FoV and the resolution of the image, the volume of the image sensor <NUM> increases. For example, to increase the sensitivity of an image while maintaining the resolution of the image, the size of each sensing element needs to be increased while maintaining the number of sensing elements included in the sensing array <NUM>, and thus the size of the sensing array <NUM> increases. In this example, to maintain the FoV, the size of the lens element <NUM> increases and the focal length of the lens element <NUM> increases as the size of the sensing array <NUM> increases, and thus the volume of the image sensor <NUM> increases.

According to the embodiment, as the size of each lens element included in the lens array <NUM> decreases, that is, as the number of lenses included in the same area on the lens array <NUM> increases, the focal length of the lens element <NUM> may decrease, and the thickness of the imaging device <NUM> may decrease. Thus, a relatively thin camera may be implemented. In this example, the imaging device <NUM> may reconstruct a high-resolution output image by rearranging and combining low-resolution images captured by each lens element <NUM>.

An individual lens element <NUM> of the lens array <NUM> may cover a predetermined sensing region <NUM> of the sensing array <NUM> corresponding to its lens size. In the sensing array <NUM>, the sensing region <NUM> covered by the lens element <NUM> may be determined according to the lens size of the corresponding lens element <NUM>. The sensing region <NUM> may be a region on the sensing array <NUM>, and rays of a predetermined range of FoV may reach the sensing region <NUM> after passing through the lens element <NUM>. The size of the sensing region <NUM> may be expressed by a distance from the center of the sensing region <NUM> to an outermost point or a diagonal length. The light passing through the imaging optical lens may be received in the sensing region <NUM> corresponding to the imaging optical lens in the sensing array <NUM>. That is, light passing through an individual lens element <NUM> may be incident to a corresponding individual sensing element of the sensing array <NUM> included in the sensing region <NUM>.

Each of the sensing elements of the sensing array <NUM> may generate sensing information based on rays passing through lenses of the lens array <NUM>. For example, the sensing element 121a may sense an intensity value of light received through the lens element <NUM> as the sensing information. The imaging device <NUM> may determine intensity information corresponding to an original signal related to points included in the FoV of the imaging device <NUM> based on the sensing information output from the sensing array <NUM>, and reconstruct the captured image based on the determined intensity information. For example, an individual sensing element 121a of the sensing array <NUM> may be an optical sensing element configured with a complementary metal-oxide-semiconductor (CMOS) or a charge-coupled device (CCD).

Further, the sensing element 121a may generate a color intensity value corresponding to a desired color as the sensing information by sensing light passing through the color filter 122a. Each of the plurality of sensing elements constituting the sensing array <NUM> may be disposed to sense a color different from that sensed by a neighboring sensing element that is spatially adjacent thereto.

When the diversity of sensing information is sufficiently secured, and a full-rank relationship is formed between the original signal information corresponding to the points included in the FoV of the imaging device <NUM> and the sensing information, a captured image corresponding to the maximum resolution of the sensing array <NUM> may be derived. The diversity of sensing information may be secured based on parameters of the imaging device <NUM>, such as the number of lenses included in the lens array <NUM> and the number of sensing elements included in the sensing array <NUM>.

In a multi-lens array structure for imaging, the imaging optical lenses and the sensing array <NUM> may be disposed in a fractional alignment structure. For example, the fractional alignment structure may be a structure in which a sensing region <NUM> covered by an individual lens element <NUM> includes a non-integer number of sensing elements. Each sensing region <NUM> of the sensing array <NUM> may include, for example, four or more sensing elements. In another example, each sensing region <NUM> may include nine or more sensing elements.

If the lens elements included in the lens array <NUM> have the same lens size, the number of lens elements included in the lens array <NUM> and the number of sensing elements included in the sensing array <NUM> may be relatively prime. A proportion P/L of the number L of lens elements corresponding to one axis of the lens array <NUM> and the number P of sensing elements corresponding to one axis of the sensing array <NUM> may be determined to be a real number. The number of sensing elements covered by each of the lens elements may be equal to the number of pixel offsets corresponding to P/L. For example, the sensing region <NUM> of <FIG> may include <NUM>/<NUM>=<NUM> sensing elements along a horizontal axis and <NUM>/<NUM>=<NUM> sensing elements along a vertical axis. Furthermore, the lens element <NUM> may cover a plurality of, for example, a non-integer number of, condensing microlenses 123a. Thus, the number of condensing microlenses 123a in the image sensor <NUM> may be equal to the number of sensing elements 121a of the sensing array <NUM>, and the number of lens elements <NUM>, for example, imaging optical lenses of the lens array <NUM> may be less than the number of condensing microlenses.

Through the fractional alignment structure as described above, the imaging device <NUM> may have a slightly different arrangement of an optical center axis (OCA) of each lens element <NUM> with respect to the sensing array <NUM>. That is, the lens element <NUM> may be eccentric with respect to the sensing element 121a. For example, at least one sensing element of the sensing array <NUM> may receive rays passing through different imaging optical lenses. Referring to the example of <FIG>, the fourth sensing element from the left may receive rays passing through the left lens element <NUM> and the middle lens element. Thus, each lens element <NUM> of the lens array <NUM> may receive different light field information. A light field (LF) may be emitted from a predetermined target point, and may be a field indicating directions and intensities of rays reflected at a predetermined point on a subject. The light field information may be information in which a plurality of light fields are combined. Since the direction of a chief ray of each lens element <NUM> also changes, each sensing region <NUM> receives different light field information. Thus, the imaging device <NUM> may optically obtain more sensing information. For sensing regions respectively corresponding to a plurality of imaging optical lenses, the image sensor <NUM> may sense intensity values of light reaching sensing elements belonging to the corresponding sensing regions. A processor of the image sensor <NUM> may reconstruct images (for example, a plurality of low-resolution images) respectively corresponding to the plurality of imaging optical lenses based on the sensed intensity values. Accordingly, the imaging device <NUM> may acquire a plurality of low-resolution input images through a variety of sensing information obtained as described above, and reconstruct a higher-resolution output image from the low-resolution input images.

<FIG> illustrates a structure of an imaging device according to an embodiment.

Referring to <FIG>, an imaging device <NUM> may include an imaging lens array <NUM>, a sensing array <NUM>, an additional lens array <NUM>, and an opening <NUM>. <FIG> illustrates only the sensing array <NUM>, but embodiments are not limited thereto, and the other sensing elements of <FIG> may be included. For example, the optical filter <NUM> and the condensing lens array <NUM> may further be disposed between the sensing array <NUM> and the imaging lens array <NUM>.

The imaging lens array <NUM> may include optical lens elements for imaging. A lens element <NUM> may also be referred to as an imaging optical lens, and the f-number of the imaging device <NUM> may be set by a focal length f of the imaging optical lens <NUM>. The imaging lens array <NUM>, the imaging optical lens <NUM>, the sensing array <NUM>, and a sensing region <NUM> are respectively the same as and/or similar to the lens array <NUM>, the lens element <NUM>, the sensing array <NUM>, and the sensing region <NUM> of <FIG>.

The opening <NUM> may include a plurality of apertures. An aperture <NUM> may be, for example, in a circular shape and transmit light. For example, the plurality of apertures may be formed along a plane corresponding to the opening <NUM>. The plurality of apertures may be formed to have a circular cross-section perpendicular to an optical axis by being filled with a transparent material. However, embodiments are not limited thereto. Rays passing through the plurality of apertures may be transmitted to subsequent optical elements corresponding to the apertures <NUM>. In <FIG>, a ray passing through the aperture <NUM> of the opening <NUM> may be transmitted to an additional lens <NUM> of the additional lens array <NUM>.

The additional lens array <NUM> may include a plurality of additional lenses <NUM>. The plurality of additional lenses <NUM> may be disposed along a virtual plane corresponding to the additional lens array <NUM>. Each of the plurality of additional lenses231 included in the additional lens array <NUM> may transmit a ray received from a previous layer, for example, the opening <NUM> of <FIG> to a subsequent layer, for example, the imaging lens array <NUM> of <FIG>.

For reference, <FIG> illustrates each of the imaging lens array <NUM> and the additional lens array <NUM>, respectively, as a single layer. However, embodiments are not limited thereto. The imaging device <NUM> may also include a plurality of imaging lens arrays <NUM> and a plurality of additional lens arrays <NUM>. Here, the imaging lens array <NUM> may be a lens array configured to finally form an image and be provided closer to the sensing array <NUM> than the additional lens array <NUM>, among the lens arrays, and the imaging lens array <NUM> and the sensing array <NUM> may face each other. If the condensing lens array <NUM> of <FIG> is disposed on the sensing array <NUM>, the condensing lens array <NUM> may be closest to the sensing array <NUM>, and the imaging lens array <NUM> may be next, for example, second) closest to the sensing array <NUM>.

Herein, the imaging lens array <NUM> and the additional lens array <NUM> may be referred to as optical lens arrays. One of the imaging lens array <NUM> may be closer to the condensing lens array <NUM> than all the other optical lens arrays. An area proportion of the non-circular imaging optical lens <NUM> to the sensing region <NUM> of the imaging lens array <NUM> closest to the image sensor <NUM> may be greater than an area proportion of a circular lens to the sensing region <NUM>. Thus, an optical power required for a ray passing through an outer portion of the non-circular imaging optical lens <NUM> to reach an outer portion of the sensing region <NUM> may decrease. That is, an optical error at the outer portion of the non-circular imaging optical lens <NUM> may decrease.

Hereinafter, a description will be provided based on optical elements through which a predetermined ray passes, on an optical path along which the ray reaches a sensing array from the aperture <NUM>. For example, the structure and arrangement of the aperture <NUM>, the additional optical lens <NUM>, the imaging optical lens <NUM>, and the sensing region <NUM> will be described, and the description may also apply to the remaining optical elements of each array similarly.

<FIG> illustrates an example of shapes of lenses included in an imaging device according to an embodiment.

Referring to <FIG>, in an imaging device, optical elements may be disposed in an order of an aperture <NUM>, an additional optical lens <NUM>, and an imaging optical lens <NUM>. As shown in <FIG>, there may be provided a plurality of additional optical lenses <NUM> and a plurality of imaging optical lenses <NUM>.

The aperture <NUM> may transmit light. The aperture <NUM> and a sensing array <NUM> may be disposed on opposite sides with respect to the imaging optical lens <NUM>.

The imaging optical lens <NUM> may have a non-circular cross-section perpendicular to a principal axis of the imaging device and transmit light received from the outside to the sensing array <NUM>. The imaging optical lens <NUM> may have a non-circular cross-section, thereby covering a larger sensing region. The imaging optical lens <NUM> may form an image on a plane of the sensing array <NUM> by refracting light received from a subject. The cross-section of the imaging optical lens <NUM> will be described below with reference to <FIG>.

The additional optical lens <NUM> may have one of a circular cross-section and a non-circular cross-section perpendicular to the principal axis, and may be disposed between the aperture <NUM> and the imaging optical lens <NUM> such that the additional optical lens <NUM> and the sensing array <NUM> may be disposed on opposite sides with respect to the imaging optical lens <NUM>. <FIG> illustrates the additional optical lens <NUM> being a circular lens. However, embodiments are not limited thereto. For example, if there are a plurality of additional optical lenses <NUM>, a portion of the plurality of additional optical lenses <NUM> may be circular lenses, and the remaining portion thereof may be non-circular lenses.

As described above, the sensing array <NUM> may include a plurality of sensing elements, and sense light passing through the imaging optical lens <NUM> using sensing elements in a sensing region.

The imaging device may further include an optical filter <NUM>. The optical filter <NUM> may be disposed between the imaging optical lens <NUM> and the sensing array <NUM> and filter out a portion of wavelengths of the light passing through the imaging optical lens <NUM>. For example, the optical filter <NUM> of <FIG> may be an infrared filter that blocks light having a wavelength of an infrared band and transmits light of a visible light band. The optical filter <NUM> of <FIG> may be different from the optical filter <NUM> in the image sensor <NUM> of <FIG>.

According to an embodiment, another imaging lens may not be disposed between the imaging optical lens <NUM> and an image sensor including the sensing array <NUM>. For example, if the imaging device includes a plurality of lenses such as the additional optical lens <NUM> and the imaging optical lens <NUM>, the imaging optical lens <NUM> facing the sensing array <NUM> may be a lens closer to the sensing array <NUM> than the additional optical lens <NUM> is.

<FIG> illustrates a non-circular imaging optical lens included in an imaging device according to an embodiment.

In <FIG>, front views of a single imaging optical lens <NUM> of a lens array and a sensing region <NUM> corresponding to the imaging optical lens <NUM> in a sensing array are illustrated.

The sensing region <NUM> may be rectangular. For example, in <FIG> illustrates the length a of a short side of the rectangular sensing region <NUM>, and the length b of a long side of the rectangular sensing region <NUM>, and the length h from the center of the rectangular sensing region <NUM> to a vertex of the rectangular sensing region <NUM>, for example, the diagonal half-length, and the diagonal length <NUM> of the sensing region <NUM>. Each of a, b, h, and <NUM> may be expressed in units of length, for example, millimeter (mm), micrometer (µm), and nanometer (nm).

A circular lens <NUM> configured to be smaller than the sensing region <NUM> covers only a portion of the sensing region <NUM>, and thus light received from the outside may not reach the remaining portion of the sensing region <NUM> not covered by the circular lens <NUM>. Further, if the circular lens <NUM> is configured to transmit light to the remaining portion of the sensing region <NUM> not covered by the circular lens <NUM>, optical aberration may occur due to excessive refraction at the outer portion of the circular lens <NUM>.

The imaging optical lens <NUM> according to an embodiment may be a lens left after cutting off a portion of a circular lens <NUM> with a diameter greater than the length a of a short side of the rectangular sensing region <NUM>. For example, the imaging optical lens <NUM> may be a lens left after cutting off a portion <NUM> of the circular lens <NUM> with a diameter greater than the length a of the short side of the rectangular sensing region <NUM>, the portion being outside of the sensing region <NUM> corresponding to the imaging optical lens <NUM>. Thus, the cross-section of the imaging optical lens <NUM> may correspond to a portion of a circle with a diameter greater than the length a of the short side of the rectangular sensing region <NUM>. Hereinafter, various shapes of the imaging optical lens <NUM> will be described with reference to <FIG>.

<FIG> illustrate examples of shapes of a non-circular imaging optical lens according to an embodiment.

Herein, an imaging optical lens <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be a lens left after cutting off a portion of a circular lens as described in <FIG>, and may be a non-circular lens. The cross-section of the imaging optical lens <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be determined according to the shape of a sensing region <NUM>. The diameter of the imaging optical lens <NUM>, <NUM>, <NUM>, <NUM>, <NUM> may be the diameter of the circular lens before the cutoff. The radius of the circular lens may be denoted by Lh. The length from the center of the imaging optical lens <NUM>, <NUM>, <NUM>, <NUM>, <NUM> to a long side of the sensing region <NUM> may be denoted by Lh'.

<FIG> illustrates an example in which the diameter of the imaging optical lens <NUM> is longer than the length a of the short side of the sensing region <NUM> and shorter than the length b of the long side of the sensing region <NUM>. The cross-section of the imaging optical lens <NUM> may include two facing arcs <NUM> and <NUM> and straight lines <NUM> and <NUM> respectively connecting ends of one arc to ends of the other arc. In the cross-section, the first straight line <NUM> may connect a first end of the first arc <NUM> to a first end of the second arc <NUM>. The second straight line <NUM> may connect a second end of the first arc <NUM> to a second end of the second arc <NUM>.

<FIG> illustrates an example in which the diameter of the imaging optical lens <NUM> is longer than the length b of the long side of the sensing region <NUM> and shorter than the diagonal length <NUM>. In addition to the upper end and the lower end of the circular lens, both side portions of the circular lens are outside of the sensing region <NUM> and thus, may be cut off. The imaging optical lens <NUM> may include four arcs <NUM>, <NUM>, <NUM>, and <NUM> and straight lines <NUM>, <NUM>, <NUM>, and <NUM> connecting the four arcs. The first arc 561and the third arc <NUM> may face each other, and the second arc <NUM> and the fourth arc <NUM> may face each other. The first straight line <NUM> may connect the first arc <NUM> to the second arc <NUM>. The second straight line <NUM> may connect the second arc <NUM> to the third arc <NUM>. The third straight line <NUM> may connect the third arc <NUM> to the fourth arc <NUM>. The fourth straight line <NUM> may connect the fourth arc <NUM> to the first arc <NUM>. The first straight line <NUM> and the third straight line <NUM> may be parallel with each other, and the second straight line <NUM> and the fourth straight line <NUM> may be parallel with each other. The first straight line <NUM> and the third straight line <NUM> may be perpendicular to the second straight line <NUM> and the fourth straight line <NUM>.

<FIG> illustrates an example in which the diameter of the imaging optical lens <NUM> is greater than or equal to the diagonal length <NUM> of the sensing region <NUM>. The cross-section of the imaging optical lens <NUM> may correspond to a portion of a circle with a diameter greater than or equal to the diagonal length <NUM> of the sensing region <NUM>. The cross-section of the imaging optical lens <NUM> left after cutting off a portion of the circular lens described above may be quadrangular. In the cross-section of the imaging optical lens <NUM>, a first straight line <NUM> and a third straight line <NUM> may be parallel with each other, and a second straight line <NUM> and a fourth straight line <NUM> may be parallel with each other. Further, the first straight line <NUM> and the third straight line <NUM> may be orthogonal to the second straight line <NUM> and the fourth straight line <NUM>.

The non-circular optical lens may have a predetermined cross-sectional area greater than or equal to that of the sensing region <NUM> facing the non-circular optical lens. <FIG> illustrates an example in which the area proportion of the non-circular optical lens <NUM> to the sensing region <NUM> is <NUM> as the maximum, and <FIG> illustrates an example in which the area proportion of the non-circular optical lens <NUM> to the sensing region <NUM> is the minimum.

<FIG> illustrates a lens <NUM> with a diameter less than the minimum diameter of the non-circular the imaging optical lens <NUM> of <FIG> before the cutoff. That is, the diameter of the non-circular the imaging optical lens <NUM> needs to be greater than the diameter of the circular optical lens <NUM>, that is, 2Lh (=a), and the area proportion of the non-circular optical lens to the sensing region needs to exceed the proportion calculated based on the circular optical lens <NUM>. In the example of <FIG>, the ratio of the cross-sectional area of the optical lens to the sensing region <NUM> that it is facing, that is, the area proportion of the circular optical lens <NUM> to the area Ssensor of the sensing region <NUM> may be expressed by Equation <NUM>.

According to Equation <NUM>, if the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the minimum area proportion may be <MAT>. That is, according to <FIG>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than <NUM> and less than or equal to <NUM>. However, the area proportion described above may vary depending on the proportion of the long side to the short side of the sensing region <NUM>. For example, if the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than <NUM> and less than or equal to <NUM>. If the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than <NUM> and less than or equal to <NUM>. If the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than <NUM> and less than or equal to <NUM>. If the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than <NUM> and less than or equal to <NUM>.

<FIG> illustrates a structure in which the diameter 2Lh of the imaging optical lens <NUM> is the same as the length of the long side b of the sensing region <NUM> in the range of size of the imaging optical lenses <NUM>, <NUM>, <NUM>, and <NUM> described with reference to <FIG>. The imaging optical lens <NUM> of <FIG> may cover all the sensing elements on one axis, for example, a horizontal axis passing through the center of the sensing region <NUM>. In the structure of <FIG>, the proportion of the area SLens,med of the imaging optical lens <NUM> to the area Ssensor of the sensing region <NUM> may be expressed by Equation <NUM>.

According to Equation <NUM>, if the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM> to the area of the sensing region <NUM> may be about <NUM>. Thus, the proportion of the cross-sectional area of the imaging optical lenses <NUM>, <NUM>, and <NUM> of <FIG>, <FIG>, and <FIG> to the area of the sensing region <NUM> may be greater than or equal to <NUM> and less than or equal to <NUM>. Similarly, if the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than or equal to <NUM> and less than or equal to <NUM>. If the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than or equal to <NUM> and less than or equal to <NUM>. If the proportion of the long side to the short side of the sensing region <NUM> is b:a=<NUM>:<NUM>, the proportion of the cross-sectional area of the non-circular imaging optical lens <NUM>, <NUM>, <NUM> to the area of the sensing region <NUM> may be greater than or equal to <NUM> and less than or equal to <NUM>.

<FIG> illustrates a relationship between a vertical length of a non-circular imaging optical lens and a diagonal length of a sensing region according to an embodiment.

As shown in <FIG>, a ray passing through an aperture of an opening <NUM> may be incident on a sensing array via an additional optical lens <NUM> and an imaging optical lens <NUM>. The imaging optical lens <NUM> may intersect with virtual straight lines <NUM> from edge points of the aperture to a boundary of a sensing region <NUM>. In a circular lens, portions not intersecting with the virtual straight lines <NUM> may be cut off. A vertical length Lh' which is based on an optical axis <NUM> in the imaging optical lens <NUM> may be less than the radius Lh of the circular lens by a cutoff length Cut-h. For example, the vertical length Lh' of the imaging optical lens <NUM> may be less than a diagonal half-length h based on the optical axis <NUM>.

The cross-section of the imaging optical lens <NUM> left after cutting off a portion of the circular lens may be in the shapes as described in <FIG>. However, embodiments are not limited thereto.

The imaging optical lens <NUM> left after cutting off a portion of the circular lens by the cutoff length Cut-h as described above may be disposed not to overlap another imaging optical lens corresponding to another sensing region in the sensing array. Further, since the imaging optical lens <NUM> intersects with a straight path from the aperture to the boundary of the sensing region <NUM>, optical aberration and distortion may be minimized until a ray passing through the aperture passes through the imaging optical lens <NUM> and reaches the sensing region <NUM>.

For reference, <FIG> only illustrates the vertical length Lh' of the non-circular imaging optical lens <NUM> and the diagonal half-length h of the sensing region on the same 2D plane to describe the length comparison. The real arrangement of the non-circular imaging optical lens <NUM> and the sensing array is not limited to the example of <FIG>. For example, the imaging optical lens <NUM> and the sensing array may be disposed as shown in <FIG>.

<FIG> illustrates optical paths of an imaging device according to an embodiment. <FIG> is a schematic top view of imaging of a chief ray and a marginal ray of an imaging optical lens <NUM>.

The imaging optical lens <NUM> may be a lens left after cutting off a portion of a circular lens with a diameter LD' to the shapes shown in <FIG>, and the diameter LD' of the circular lens may be the same as or similar to the diagonal length SD' of a sensing region.

Here, at an outer portion <NUM> of the imaging optical lens <NUM>, a first refraction angle θ' of a first ray <NUM> incident along a path parallel with a virtual straight line from a center of the imaging optical lens <NUM> to a boundary of a sensing region <NUM> may be similar to a second refraction angle Φ' of a second ray <NUM> incident parallel with an optical axis of the imaging optical lens <NUM>. The outer portion <NUM> may include, for example, points spaced apart from the center of the imaging optical lens <NUM> by the diagonal half-length h of the sensing region <NUM> and neighboring points thereof. The first ray <NUM> may be refracted by the outer portion <NUM> of the imaging optical lens <NUM> and reach the boundary of the sensing region <NUM>. The second ray <NUM> may be refracted by the same outer portion <NUM> and reach the center of the sensing region <NUM>, for example, a focal point. The image sensor may receive the first ray <NUM> at the boundary of the sensing region <NUM>, the first ray <NUM> incident parallel with the virtual straight line from the center of the imaging optical lens <NUM> to the boundary of the sensing region <NUM> and refracted by the outer portion of the imaging optical lens <NUM> at the first refraction angle θ'. Further, the image sensor may receive the second ray <NUM> at the center of the sensing region <NUM>, the second ray <NUM> incident parallel with the optical axis of the imaging optical lens <NUM> and refracted by the outer portion of the imaging optical lens <NUM> at the second refraction angle Φ'. As a difference between the first refraction angle θ' and the second refraction angle Φ' decreases, an imaging device may acquire an image of a subject with reduced optical aberration and distortion.

Further, a difference between a first light path along which the first ray <NUM> reaches the sensing array and a second light path along which the second ray <NUM> reaches the sensing array may be less than a threshold path difference. That is, in the imaging optical lens, a difference in optical path length (OPD) between light passing through a <NUM> field of the lens, for example, light toward the center of the sensing region and light passing through a <NUM> filed of the lens, for example, light toward the boundary of the sensing region may decrease. As the difference in OPD decreases, optical aberration and distortion may be reduced. For example, in a camera lens implemented on a smart phone, the maximum size of a half size of the lens in a <NUM> field and a <NUM> field may be <NUM>. Further, a difference in OPD between light passing through the <NUM> field and reaching a sensor and light passing through the <NUM> field and reaching the sensor may be within <NUM>.

<FIG> and <FIG> illustrate modulation transfer functions (MTFs) according to an embodiment.

<FIG> illustrates a side view of a structure of the imaging device of <FIG> and an MTF of the imaging device. <FIG> illustrates a side view of a structure of another imaging device including circular lenses <NUM> that is different from <FIG>, and an MTF of the device. An MTF may be a type of index indicating an optical performance. In MTF graphs <NUM> and <NUM>, a vertical axis may indicate an MTF value, and a horizontal axis may indicate a spatial frequency. In the MTF graphs <NUM> and <NUM>, individual lines may indicate the transition of MTF values of rays incident to an aperture at a predetermined angle of incidence. The transition of the MTF values may be represented depending on a spatial frequency. The angle of incidence may be an angle about a vertical normal of a boundary surface of incidence.

In the structure of the imaging device of <FIG>, rays passing through the center of the aperture of the opening <NUM> and the boundary may pass through the additional optical lens <NUM>, the imaging optical lens <NUM>, and the optical filter <NUM> and reach the sensing region <NUM>. In the structure of the device of <FIG>, rays passing through the aperture of the opening <NUM> may pass through the circular lenses <NUM> and the optical filter <NUM> and reach the sensing region <NUM>. A ray vertically incident to the aperture may pass through a central portion of the imaging optical lens <NUM> at the rearmost end in the structure of the imaging device of <FIG>, and may pass through a central portion of the circular lens <NUM> at the rearmost end in the structure of the device of <FIG>. As the angle of incidence formed by the aperture and the ray increases, the ray may pass through a portion, for example, an outer portion farther away from the central portion of the imaging optical lens <NUM> at the rearmost end and a portion, for example, an outer portion farther away from the central portion of the circular lens <NUM> at the rearmost end.

The MTF does not greatly decrease even with respect to light passing through the outer portion of the imaging optical lens <NUM> as a ray with a great angle of incidence. Conversely, in the MTF graph <NUM> of the device of <FIG>, an MTF value <NUM> of light passing through the outer portion of the circular lens <NUM> as a ray with a great angle of incidence with respect to the aperture may be attenuated drastically as the spatial frequency increases. Thus, in the MTF graph <NUM> of the imaging device of <FIG>, an MTF with a stable value for each angle of incidence of a ray and for each spatial frequency may be represented.

<FIG> illustrates a lens array including non-circular lenses in an imaging device according to an embodiment.

An imaging device may include, as an imaging array, a lens array <NUM> in which a plurality of non-circular imaging optical lenses are arranged. For example, the lens array <NUM> may include an imaging optical lens <NUM> and an additional imaging optical lens provided in the same shape and the same size as the imaging optical lens <NUM>. The imaging optical lens <NUM> and the additional imaging optical lens may be disposed along the same plane. A sensing region <NUM> covered by the imaging optical lens <NUM> and a sensing region covered by the additional imaging optical lens may be the same in size and shape.

In <FIG>, a structure in which the size of the sensing array is M×N (mm) and the lens array <NUM> includes <NUM>×<NUM> imaging optical lenses is illustrated. A sensing region occupied by each imaging optical lens <NUM> in the sensing array may be in the size of M/<NUM>×N/<NUM>.

<FIG> illustrates a valid sensing region by a quadrangular lens in an imaging device according to an embodiment.

A different valid sensing region may be available depending on the size of a lens in a sensing region of the same size. For example, if a circular imaging lens <NUM> is used in a lens array, the lens may not protrude out of a sensing region <NUM> allocated to each circular imaging lens <NUM>. Thus, the diameter of the circular imaging lens <NUM> may be limited to the length of a short side of the sensing region or below. In this example, a valid sensing region <NUM> of the circular imaging lens <NUM> may be limited to a portion of the sensing region <NUM>, as shown in <FIG>. For example, if the sensing array includes sensing elements supporting a resolution of up to <NUM> (<NUM>,<NUM>×<NUM>), the resolution of the valid sensing region <NUM> of the circular imaging lens <NUM> may be limited to <NUM>.

On the contrary, if a non-circular imaging lens is used as described with reference to <FIG>, a valid sensing region <NUM> of the non-circular imaging lens <NUM> may be substantially the same or similar to the sensing region <NUM>, and thus the resolution of the valid sensing region <NUM> may be around <NUM>. When the non-circular imaging lens <NUM> is disposed, the imaging device may use a full region of the sensing region <NUM>. Thus, the imaging device including the non-circular imaging lens <NUM> may capture an image of an increased resolution with respect to the same sensing region <NUM>, when compared to the circular imaging lens <NUM>.

<FIG> illustrates a quadrangular lens as the non-circular imaging lens <NUM>, but embodiments are not limited thereto. The non-circular imaging lens <NUM> may have a cross-section of a modified quadrangular shape, in addition to a rectangular cross-section and a square cross-section.

<FIG> illustrates a lens array including quadrangular lenses in an imaging device according to an embodiment.

In a lens array in which lens elements are disposed along a plane in a grid pattern, if the diameter LD' of each circular lens <NUM> is greater than or equal to the diagonal length SD' of an individual sensing region <NUM>, each circular lens <NUM> may include regions overlapping other circular lenses <NUM>. Since lenses cannot overlap physically, a non-circular imaging optical lens <NUM> may be provided in a shape left after cutting off a portion of the circular lens <NUM> with the diameter LD' greater than or equal to the diagonal length SD' of the sensing region <NUM>. For example, portions of the circular lens <NUM> overlapping other circular lenses <NUM> may be cut off. As shown in <FIG>, the non-circular imaging optical lens <NUM> left after cutting off a portion of the circular lens <NUM> with the diameter LD' greater than or equal to the diagonal length SD' of the sensing region <NUM> may have a quadrangular cross-section. For reference, although <FIG> illustrates the lens array including non-circular imaging optical lenses <NUM> each having a quadrangular cross-section perpendicular to an optical axis of the same shape, embodiments are not limited thereto. The shape of at least one imaging lens may be different from the shape of another imaging lens in the lens array.

As described above, since a full region of each sensing region <NUM> may be covered by an imaging optical lens having a quadrangular cross-section, the lens performance may be maximized, and optical aberration may be reduced. Thus, the imaging device may acquire an image of a subject with a more improved resolution.

<FIG> is a block diagram illustrating a configuration of an imaging device according to an embodiment. <FIG> illustrates a mobile terminal according to an embodiment.

Referring to <FIG>, an imaging device <NUM> may include an opening <NUM>, an additional optical lens <NUM>, an imaging optical lens <NUM>, a sensing array <NUM>, and a processor <NUM>. There may be provided N additional optical lenses <NUM> and N imaging optical lens <NUM>. Here, N may be an integer greater than or equal to <NUM>. The additional optical lens <NUM> may be provided as at least one layer, and the imaging optical lens <NUM> may be provided as at least one layer. The sensing array <NUM> may include sensing elements configured to generate electrical signals by sensing light. The opening <NUM>, the additional optical lens <NUM>, the imaging optical lens <NUM>, and the sensing array <NUM> are as described above with reference to <FIG>. An assembly including the imaging optical lens <NUM> and the sensing array <NUM> may be an image sensing assembly. The image sensing assembly may further include one of an opening <NUM>, an additional optical lens <NUM>, the optical filter <NUM> as illustrated in <FIG>, and the condensing lens array <NUM> as illustrated in <FIG>, or a combination of two or more thereof, depending on the design, in addition to the imaging optical lens <NUM> and the sensing array <NUM>.

The processor <NUM> may obtain information related to a subject through the opening <NUM>, the additional optical lens <NUM>, and the imaging optical lens <NUM> and reconstruct an image of the subject. For example, the processor <NUM> may generate the image based on sensing information sensed by the sensing array <NUM>. The processor <NUM> may acquire an image corresponding to an individual sensing region from sensing information sensed in the corresponding sensing region. The processor <NUM> may acquire images as many as sensing regions constituting the sensing array <NUM>. The processor <NUM> 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 <NUM> is not limited thereto.

The imaging device <NUM> may be implemented as a mobile terminal <NUM> shown in <FIG>.

An image sensing assembly <NUM> of the mobile terminal <NUM> may be implemented in an ultra-thin structure through an image lens array <NUM> including non-circular imaging optical lenses, for example, lenses having quadrangular cross-sections. The image sensing assembly <NUM> may receive external light through the non-circular imaging optical lenses and generate sensing information by sensing the external light using a plurality of sensing elements. For example, the image sensing assembly <NUM> may include a sensing array <NUM>, an optical filter <NUM>, a condensing lens array <NUM>, an imaging lens array <NUM>, an additional lens array <NUM>, and an opening <NUM>. The elements of the image sensing assembly <NUM> are as described above with reference to <FIG>, and thus a detailed description will be omitted for conciseness.

The image sensing assembly <NUM> may be implemented as a smart phone camera, a DSLR camera, or a camera module for vision for vehicular/drone/CCTV recognition. For example, at least one of a rear camera <NUM> and a front camera <NUM> of the mobile terminal <NUM> may be the image sensing assembly <NUM>. The rear camera <NUM> may include a plurality of rear camera modules, and at least one of the plurality of rear camera modules may be the image sensing assembly <NUM>. Further, the front camera <NUM> may include one or more front camera modules, and at least one of the one or more front camera modules may be the image sensing assembly <NUM>.

The rear camera <NUM> and a display <NUM> may be disposed on different sides, for example, on opposite sides, in a housing of the mobile terminal <NUM>. A rear side may be a side opposite the side on which the display <NUM> is disposed in the mobile terminal <NUM>. The front camera <NUM> and the display <NUM> may be disposed on the same side in the housing of the mobile terminal <NUM>. A front side may be the side on which the display <NUM> is disposed in the mobile terminal <NUM>.

The image sensing assembly <NUM> of an ultra-thin structure may transmit light to the sensing array <NUM> through the imaging lens array <NUM>, and the processor <NUM> of the mobile terminal <NUM> may acquire an image of a subject through the sensing array <NUM>. The processor <NUM> may reconstruct an output image based on sensing information generated by the image sensing assembly <NUM>. For example, the processor <NUM> may acquire as many images as a number of sensing regions constituting the sensing array <NUM>, as described with reference to <FIG>. An input image acquired for each sensing region may be a relatively low-resolution image. The processor <NUM> may reconstruct a single high-resolution output image with respect to the image sensing assembly <NUM> by rearranging and/or reconfiguring images generated based on the sensing information. For reference, although <FIG> illustrates a single processor <NUM>, embodiments are not limited thereto. The mobile terminal <NUM> may include a plurality of processors, and at least one processor <NUM> among the plurality of processors may perform image processing with respect to the sensing information sensed by the image sensing assembly <NUM>.

The memory <NUM> may store at least one of the sensing information and the output image. For example, the memory <NUM> may temporarily or permanently store data required or computed by the processor <NUM> during a process of reconstructing the high-resolution output image from the sensing information.

<FIG> is a flowchart illustrating an image sensing method according to an embodiment.

First, in operation <NUM>, 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 principal axis of the imaging device.

In operation <NUM>, the imaging device may sense the light passing through the imaging optical lens using sensing elements in a sensing region of a sensing array.

However, the image sensing method is not limited to the above description, and may be performed concurrently in parallel and/or sequentially with at least one of the operations described above with reference to <FIG>.

The units described herein may be implemented using a hardware component, a software component and/or a combination thereof. A processing device may be implemented using one or more general-purpose or special purpose computers, such as, for example, a processor, a controller and an arithmetic logic unit (ALU), a digital signal processor (DSP), a microcomputer, an field-programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor or any other device capable of responding to and executing instructions in a defined manner. The processing device may run an operating system (OS) and one or more software applications that run on the OS. The processing device also may access, store, manipulate, process, and create data in response to execution of the software. For purpose of simplicity, the description of a processing device is used as singular, however, one skilled in the art will appreciate that a processing device may include multiple processing elements and multiple types of processing elements. For example, a processing device may include multiple processors or a processor and a controller. In addition, different processing configurations are possible, such a parallel processors.

The software may include a computer program, a piece of code, an instruction, or some combination thereof, to independently or collectively instruct or configure the processing device to operate as desired.

The methods according to the above-described embodiments may be recorded in non-transitory computer-readable media including program instructions to implement various operations of the above-described embodiments. The program instructions recorded on the media may be those specially designed and constructed for the purposes of embodiments, or they may be of the kind well-known and available to those having skill in the computer software arts. The above-described devices may be configured to act as one or more software modules in order to perform the operations of the above-described embodiments, or vice versa.

Claim 1:
An imaging device (<NUM>, <NUM>, <NUM>) comprising:
a sensing array (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising a plurality of sensing elements (121a);
an imaging lens array (<NUM>, <NUM>, <NUM>) comprising a plurality of imaging optical lenses (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>-<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), each of the plurality of imaging optical lenses (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>-<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) having a non-circular cross-section perpendicular to an optical axis (<NUM>), and configured to transmit light received from an outside of the imaging device (<NUM>, <NUM>, <NUM>); and
a condensing lens array (<NUM>, <NUM>) comprising a plurality of condensing lenses (123a) disposed between the imaging lens array (<NUM>, <NUM>, <NUM>) and the sensing array (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>), and configured to transmit the light passing through the imaging lens array (<NUM>, <NUM>, <NUM>) to the sensing elements (121a),
wherein a number of the plurality of imaging optical lenses (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>-<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is less than a number of the plurality of condensing lenses (123a),
each of the plurality of imaging optical lenses (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>-<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) covers a non-integer number of sensing elements (121a) included in a sensing region (<NUM>) of the sensing array (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>).