Patent Description:
A hologram has been known as the principle of the most perfect 3D display having both binocular parallax and monocular parallax effects, that is, elements that a person can feel a three-dimensional (<NUM>-D) effect. Research of a holographic display based on such a principle is actively carried out worldwide. The holographic display reproduces a <NUM>-D image based on the phase and amplitude of input light.

Known in the art is <CIT> which discloses an optical modulating device that includes a permittivity change layer having a variable permittivity, a dielectric layer disposed on the permittivity change layer, a nanoantenna disposed on the dielectric layer, and a light-emitting structure disposed adjacent to the permittivity change layer.

<CIT> discloses various embodiments that may provide a device for controlling an electromagnetic wave. The device may include a first electrode layer. The device may also include a second electrode layer. The device may further include a matrix layer between the first electrode layer and the second electrode layer. The matrix layer may include a liquid crystal layer. The matrix layer may also include at least one resonator element in contact with the liquid crystal layer. The liquid crystal layer may be configured to switch from, at least, a first state to a second state in response to a voltage applied between the first electrode layer and the second electrode layer, thereby changing an optical property of the matrix layer to control the electromagnetic wave received by the matrix layer.

<CIT> discloses an optical modulation device that includes a plasmonic nano-antenna layer, a metal layer that faces the plasmonic nano-antenna layer, and a permittivity variation layer and a dielectric material layer between the plasmonic nano-antenna layer and the metal layer. An active area formed in the permittivity variation layer according to an external signal may function as a gate that controls optical modulation performance.

<CIT> discloses a spectro-sensor which includes a nano antenna array. The nano antenna array includes a plurality of nano antennas which have different resonance wavelength bands and an optical detector array which includes a plurality of optical detectors that respectively detect light from the plurality of nano antennas.

However, a holographic display, such as that described above, displays an image by modulating any one of the phase or amplitude of light. Accordingly, there is a problem in that an image displayed on the holographic display includes noise. In order to solve such a problem, the holographic display may be equipped with a filtering optical system for removing noise. However, if the holographic display includes the filtering optical system, there is a limit in achieving a reduction in the size, a reduction in the weight, light and thinness, and mobility of the holographic display. Accordingly, there is a need for a method for enabling a holographic display to display an image without noise even without including a filtering optical system.

According to the claimed invention, an active complex spatial light modulation apparatus for an ultra-low noise holographic display according to claim <NUM> is provided.

According to various embodiments according to the claimed invention, in the active complex spatial light modulation apparatus, three petal patterns divide a complex plane into three phase sections, and represent the input light amplitude values corresponding to the phase sections. Accordingly, the phase and amplitude of light is modulated at the same time by the petal patterns. Accordingly, a holographic display can display an image without noise. As a result, the holographic display can display an image clearly without noise even without a filtering optical system.

Hereinafter, various embodiments of this document are described in detail with reference to the accompanying drawings.

The embodiments of this document and the terms used in the embodiments are not intended to limit the technology described in this document to a specific embodiment, but should be construed as including various changes, equivalents and/or alternatives of a corresponding embodiment. Regarding the description of the drawings, similar reference numerals may be used in similar elements. An expression of the singular number may include an expression of the plural number unless clearly defined otherwise in the context. In this document, an expression, such as "A or B", "at least one of A or/and B", "A, B or C" or "at least one of A, B and/or C", may include all of possible combinations of listed items together. Expressions, such as "a first," "a second," " the first" and "the second", may modify corresponding elements regardless of the sequence and/or importance, and are used to only distinguish one element from the other element and do not limit corresponding elements. When it is described that one (e.g., first) element is "(operatively or communicatively) connected to" or "coupled with" the other (e.g., second) element, one element may be directly connected to the other element or may be connected to the other element through another element (e.g., third element).

According to various embodiments according to the claimed invention, a holographic display may display an ultra-low noise <NUM>-D image using an active complex spatial light modulation apparatus. The active complex spatial light modulation apparatus is configured to control the phase and amplitude of light related to the image. The active complex spatial light modulation apparatus is configured to modulate the input light into amplitude values of three phases corresponding to three phase sections.

<FIG> is a diagram showing an active complex spatial light modulation apparatus <NUM> not according to the claimed invention. <FIG> is a diagram for illustrating the design principle of the active complex spatial light modulation apparatus <NUM> according to various embodiments according to the claimed invention. <FIG> is a diagram for illustrating an operating method of the active complex spatial light modulation apparatus <NUM> which is useful for understanding but not according to the claimed invention.

The active complex spatial light modulation apparatus <NUM> according to various embodiments according to the claimed invention is implemented in a pixel structure form, and includes a substrate <NUM> and a petal antenna <NUM> having a point symmetry configuration.

The substrate <NUM> may support the petal antenna <NUM>. For example, the substrate <NUM> may be made of a silicon dioxide material. The substrate <NUM> may include a first face, a second face, and a third face connecting the first face and the second face. For example, light related to an image may pass from the first face to the second face.

The petal antenna <NUM> may be positioned in the substrate <NUM>. For example, the petal antenna <NUM> may be positioned in the second face of the substrate <NUM>. Accordingly, light related to an image may be input from the substrate <NUM> to the petal antenna <NUM>. Furthermore, the petal antenna <NUM> modulates the phase and amplitude of the input light at the same time. The petal antenna <NUM> has a point symmetry shape on the basis of the center point C of the petal antenna <NUM>.

Petal patterns <NUM>, <NUM>, and <NUM> divide a complex plane into three phase sections, and represent input light as amplitude values A1, A2, and A3 of three phases corresponding to the phase sections. To this end, the petal antenna <NUM> includes the three petal patterns <NUM>, <NUM>, and <NUM>. Each of the petal patterns <NUM>, <NUM>, and <NUM> has a point symmetry shape on the basis of the center point C. The petal patterns <NUM>, <NUM>, and <NUM> may interact at the center point C. For example, the petal patterns <NUM>, <NUM>, and <NUM> may be tilted mutually by <NUM>°. The amplitude values A1, A2, and A3 are determined based on the sizes of the petal patterns <NUM>, <NUM>, and <NUM>. For example, each of the amplitude values A1, A2, and A3 may be adjusted by at least any one of the width or length of each of the petal patterns <NUM>, <NUM>, and <NUM>.

To perform an active operation, an element (e.g., LCD) for modulating the amplitude of a light wave actively is attached to the petal element (i.e., wing) part of each of the fixed petal patterns <NUM>, <NUM>, and <NUM>, and the amplitude of each of the three petal patterns <NUM>, <NUM>, and <NUM> is adjusted.

The petal patterns <NUM>, <NUM>, and <NUM> include a first petal pattern <NUM>, a second petal pattern <NUM>, and a third petal pattern <NUM> corresponding to the phase sections, respectively. For example, the second petal pattern <NUM> may be tilted clockwise by <NUM>° from the first petal pattern <NUM>. The third petal pattern <NUM> may be tilted clockwise by <NUM>° from the second petal pattern <NUM>. The phase sections include a first phase section, a second phase section and a third phase section. For example, the first phase section may correspond to at least some section of <NUM>° to <NUM>°, the second phase section may correspond to at least some section of <NUM>° to <NUM>°, and the third phase section may correspond to at least some section of <NUM>° to <NUM>°. The amplitude values A1, A2, and A3 include a first amplitude value A1, a second amplitude value A2, and a third amplitude value A3. The petal patterns <NUM>, <NUM>, and <NUM> may be designed to satisfy Equation <NUM> below based on a principle, such as that shown in <FIG>.

The first petal pattern <NUM> may detect the first phase section from input light, and may represent the input light as the first amplitude value A1 corresponding to the first phase section.

To perform an active operation, the amplitude of each of the three petal patterns <NUM>, <NUM>, and <NUM> is adjusted by attaching an element (e.g., LCD) for actively modulating the amplitude of a light wave to the petal element (i.e., wing) part of each of the fixed petal patterns <NUM>, <NUM>, and <NUM>. Each of the petal patterns <NUM>, <NUM>, and <NUM> includes at least two petal elements. In each of the petal patterns <NUM>, <NUM>, and <NUM>, the petal elements are arranged in a point symmetry form on the basis of a center point C. For example, the petal elements may be arranged to be extended in a radial shape from the center point C. The petal antenna <NUM> may be implemented as a hexa petal structure. According to an embodiment, at least any one of the petal patterns <NUM>, <NUM>, and <NUM> may be connected at the center point C. For example, at least any one of the petal patterns <NUM>, <NUM>, and <NUM> may have a rod shape that penetrates the center point C. According to another embodiment, at least any one of the petal patterns <NUM>, <NUM>, and <NUM> may be spaced apart from each other with the center point C interposed therebetween. For example, at least any one of the petal patterns <NUM>, <NUM>, and <NUM> may be positioned on the side opposite the other petal pattern with the center point C interposed therebetween. According to various embodiments of the claimed invention, the active complex spatial light modulation apparatus <NUM> represents input light as three-phase amplitude values A1, A2, and A3 based on three phase sections divided from a complex plane, and may then combine the three-phase amplitude values A1, A2, and A3 into a single complex value. In this case, the input light may be generated in a right circular polarization (RCP) or left circular polarization (LCP) form as a phase difference between an x-axis component and y-axis component of coherent light occurs. As shown in <FIG>, when the petal antenna <NUM> detects input light, the petal antenna <NUM> may modulate the input light as three-phase amplitude values A1, A2, and A3, corresponding to three phase sections divided from a complex plane, through the petal patterns <NUM>, <NUM>, and <NUM>. In this case, the petal antenna <NUM> may modulate the phase difference between the x-axis component and y-axis component of the coherent light, passing through the petal antenna <NUM>, in a cross polarization component contrary to the input light.

Each of the petal patterns <NUM>, <NUM> and <NUM> performs a passive operation, such that each petal pattern generates a fixed <NUM>-D image. A first amplitude value A1 is determined based on the size of the first petal pattern <NUM>. For example, the first amplitude value A1 may be adjusted by at least any one of the width or length of the first petal pattern <NUM>. The second petal pattern <NUM> may detect a second phase section from input light, and may represent the input light as a second amplitude value A2 corresponding to the second phase section. The second amplitude value A2 is determined based on the size of the second petal pattern <NUM>. For example, the second amplitude value A2 may be adjusted by at least any one of the width or length of the second petal pattern <NUM>. The third petal pattern <NUM> may detect a third phase section from the input light, and may represent the input light as a third amplitude value A3 corresponding to the third phase section. The third amplitude value A3 is determined based on the size of the third petal pattern <NUM>. For example, the third amplitude value A3 may be adjusted by at least any one of the width or length of the third petal pattern <NUM>.

<FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG> and <FIG> are diagrams for illustrating the valid width sections and valid length sections of the petal patterns <NUM>, <NUM>, and <NUM> in the visible ray passive complex spatial light modulation apparatus <NUM> according to various embodiments, whereby <FIG>, <FIG>, <FIG>, <FIG> and <FIG> are according to and <FIG> and <FIG> are not according to the claimed invention. <FIG> illustrates the valid width sections and valid length sections of the petal patterns <NUM>, <NUM>, and <NUM>. In this case, <FIG> may illustrate the valid width sections and valid length sections of the petal patterns <NUM>, <NUM>, and <NUM> if a total pixel cycle is <NUM>. <FIG> and <FIG> are diagrams illustrating the verification results of the valid width sections and valid length sections of <FIG>. <FIG>, <FIG>, <FIG> and <FIG> are diagrams illustrating the modulation results of the petal patterns <NUM>, <NUM>, and <NUM> based on the valid width sections and valid length sections of <FIG>.

Referring to <FIG>, the valid width section and valid length section of each of the petal patterns <NUM>, <NUM>, and <NUM> may be defined. The amplitude values A1, A2, and A3 of the petal patterns <NUM>, <NUM>, and <NUM> are determined based on the size of the petal patterns <NUM>, <NUM>, and <NUM>. In this case, each of the amplitude values A1, A2, and A3 may be adjusted by at least any one of the width or length of the petal patterns <NUM>, <NUM>, and <NUM>. The valid width sections of all the petal patterns <NUM>, <NUM>, and <NUM> may be the same as those shown in <FIG>, and the valid length sections of all the petal patterns <NUM>, <NUM>, and <NUM> may be the same as those shown in <FIG>. In this case, in the valid width sections of the petal patterns <NUM>, <NUM>, and <NUM>, a phase difference between cross polarization components passing through the respective petal patterns <NUM>, <NUM>, and <NUM> is <NUM>° as shown in <FIG>. In the valid length sections of the petal patterns <NUM>, <NUM>, and <NUM>, a phase difference between the cross polarization components passing through the respective petal patterns <NUM>, <NUM>, and <NUM> is <NUM>° as shown in <FIG>. For example, the width of each of the petal patterns <NUM>, <NUM>, and <NUM> may be adjusted to any one value of approximately <NUM> to <NUM>. The length of each of the petal patterns <NUM>, <NUM>, and <NUM> may be adjusted to any one value of approximately <NUM> to <NUM>.

For example, in the valid width sections of the petal patterns <NUM>, <NUM>, and <NUM>, each of the widths W1, W2, and W3 of the petal patterns <NUM>, <NUM>, and <NUM> for representing each of the amplitude values A1, A2, and A3 as <NUM> may be determined as in Table <NUM> based on a phase interval of <NUM>°. According to a first embodiment not according to the claimed invention, as shown in <FIG>, each of the petal patterns <NUM>, <NUM>, and <NUM> may include two petal elements, and the petal elements of the petal patterns <NUM>, <NUM>, and <NUM> may be interconnected at the center point C. In this case, each of the widths W1, W2, and W3 of the petal patterns <NUM>, <NUM>, and <NUM> may be determined based on Table <NUM>. According to the first embodiment, the modulation results of the petal patterns <NUM>, <NUM>, and <NUM> may show continuity in the phase sections, as shown in <FIG>. According to a second embodiment according to the claimed invention, as shown in <FIG>, each of the petal patterns <NUM>, <NUM>, and <NUM> may include two petal elements, and at least two petal elements of the petal patterns <NUM>, <NUM>, and <NUM> are spaced apart from each other with the center point C interposed therebetween. In this case, each of the widths W1, W2, and W3 of the petal patterns <NUM>, <NUM>, and <NUM> may be determined based on Table <NUM>. According to the second embodiment, the modulation results of the petal patterns <NUM>, <NUM>, and <NUM> may show further improved continuity in the phase sections, as shown in <FIG>.

For example, in the valid length sections of the petal patterns <NUM>, <NUM>, and <NUM>, each of the lengths L1, L2, and L3 of the petal patterns <NUM>, <NUM>, and <NUM> for representing each of the amplitude values A1, A2, and A3 as <NUM> may be determined as in Table <NUM> based on a phase interval of <NUM>°. According to a first embodiment not according to the claimed invention, as shown in <FIG>, each of the petal patterns <NUM>, <NUM>, and <NUM> may include two petal elements, and the petal elements of the petal patterns <NUM>, <NUM>, and <NUM> may be interconnected at the center point C. In this case, the lengths L1, L2, and L3 of the petal patterns <NUM>, <NUM>, and <NUM> may be determined based on Table <NUM>. According to the first embodiment, the modulation results of the petal patterns <NUM>, <NUM>, and <NUM> may show continuity in the phase sections as shown in <FIG>. According to a second embodiment according to the claimed invention, as shown in <FIG>, each of the petal patterns <NUM>, <NUM>, and <NUM> may include two petal elements, and at least two petal elements of the petal patterns <NUM>, <NUM>, and <NUM> are spaced apart from each other with the center point C interposed therebetween. In this case, the lengths L1, L2, and L3 of the petal patterns <NUM>, <NUM>, and <NUM> may be determined based on Table <NUM>. According to the second embodiment, the modulation results of the petal patterns <NUM>, <NUM>, and <NUM> may show further improved continuity in the phase sections as shown in <FIG>.

<FIG> is a diagram for illustrating performance of the active complex spatial light modulation apparatus <NUM> according to an embodiment.

Referring to <FIG>, each of the petal patterns <NUM>, <NUM>, and <NUM> of the active complex spatial light modulation apparatus <NUM> according to an embodiment may include two petal elements. The petal elements of the petal patterns <NUM>, <NUM>, and <NUM> may be interconnected at the center point C. Each of the petal patterns <NUM>, <NUM>, and <NUM> has a point symmetry shape on the basis of a center point C. The petal patterns <NUM>, <NUM>, and <NUM> may intersect at the center point C.

As shown in <FIG>, the first petal pattern <NUM> may detect a first phase section from input light, and may represent the input light as a first amplitude value A1 corresponding to the first phase section. As shown in <FIG>, the second petal pattern <NUM> may detect a second phase section, delayed by <NUM>° from the first phase section, from the input light, and may represent the input light as a second amplitude value A2 corresponding to the second phase section. As shown in <FIG>, the third petal pattern <NUM> may detect a third phase section, delayed by <NUM>° from the second phase section, from the input light, and may represent the input light as a third amplitude value A3 corresponding to the third phase section.

Accordingly, as shown in <FIG>, the petal patterns <NUM>, <NUM>, and <NUM> of the active complex spatial light modulation apparatus <NUM> can represent the amplitude values A1, A2, and A3 by combining them into a single complex value. Accordingly, a holographic display may display an ultra-low noise image using the active complex spatial light modulation apparatus <NUM>. That is, holographic display can display an image clearly without noise.

<FIG> are diagrams for illustrating performance of the active complex spatial light modulation apparatus <NUM> according to another embodiment according to the claimed invention. Referring to <FIG>, each of the petal patterns <NUM>, <NUM>, and <NUM> of the active complex spatial light modulation apparatus <NUM> according to another embodiment according to the claimed invention includes at least two petal elements. Each of the petal patterns <NUM>, <NUM>, and <NUM> has a point symmetry shape on the basis of a center point C. The petal patterns <NUM>, <NUM>, and <NUM> may intersect at the center point C. In some embodiments, at least any one of the petal patterns <NUM>, <NUM>, and <NUM> may be spaced apart from each other with the center point C interposed therebetween. In some embodiments, at least any one of the petal patterns <NUM>, <NUM>, and <NUM> may be interconnected at the center point C.

The petal elements include all of wide phase delay structures capable of producing three-phase (e.g., <NUM>°, <NUM>°, <NUM>°) phase delay.

As shown in <FIG>, when the petal antenna <NUM> detects input light, the petal antenna <NUM> may represent the input light as three-phase amplitude values A1, A2, and A3, corresponding to divided three phase sections, through the petal patterns <NUM>, <NUM>, and <NUM>. The first petal pattern <NUM> may detect the first phase section from the input light, and may represent the input light as the first amplitude value A1 corresponding to the first phase section. The second petal pattern <NUM> may detect the second phase section, delayed by <NUM>° from the first phase section, from the input light, and may represent the input light as the second amplitude value A2 corresponding to the second phase section. The third petal pattern <NUM> may detect the third phase section, delayed by <NUM>° from the second phase section, from the input light, and may represent the input light as the third amplitude value A3 corresponding to the third phase section.

Accordingly, the petal patterns <NUM>, <NUM>, and <NUM> of the active complex spatial light modulation apparatus <NUM> can represent the amplitude values A1, A2, and A3 by combining them into a single complex value. Accordingly, a holographic display can display an ultra-low noise image using the active complex spatial light modulation apparatus <NUM>. That is, the holographic display can display an image clearly without noise.

The active complex spatial light modulation apparatus <NUM> according to various embodiments according to the claimed invention is for an ultra-low noise holographic display, and includes the substrate <NUM> and the petal antenna <NUM> including the three petal patterns <NUM>, <NUM>, and <NUM> arranged on the substrate <NUM>, dividing a complex plane into three phase sections, and modulating input light into three-phase amplitude values A1, A2, and A3 corresponding to the phase sections.

According to various embodiments, the active complex spatial light modulation apparatus <NUM> may be implemented in a pixel structure form.

The petal antenna <NUM> has a point symmetry shape on the basis of the center point C of the petal antenna <NUM>.

According to various embodiments, the petal patterns <NUM>, <NUM>, and <NUM> may intersect at the center point C.

Each of the petal patterns <NUM>, <NUM>, and <NUM> has a point symmetry shape on the basis of the center point C.

According to various embodiments, the petal patterns <NUM>, <NUM>, and <NUM> may be mutually tilted by <NUM>°.

Each of the petal patterns <NUM>, <NUM>, and <NUM> includes at least two petal elements arranged in a point symmetry form on the basis of the center point C.

According to an embodiment, at least two of the petal elements may be interconnected at the center point C.

At least two of the petal elements are spaced apart from each other with the center point C interposed therebetween.

According to various embodiments, each of the amplitude values A1, A2, and A3 may be adjusted based on at least any one of the width or length of each of the petal patterns <NUM>, <NUM>, and <NUM>.

An operating method of the active complex spatial light modulation apparatus <NUM> according to various embodiments which do not form part of the claimed invention may include detecting, by the petal antenna <NUM> including the three petal patterns <NUM>, <NUM>, and <NUM> arranged on the substrate <NUM>, light input to the center point of the petal antenna <NUM>, and modulating, by the petal antenna <NUM>, the input light into three-phase amplitude values A1, A2, and A3 corresponding to three phase sections divided from a complex plane through the petal patterns <NUM>, <NUM>, and <NUM>.

According to various embodiments, each of the amplitude values may be adjusted based on transmittance of a display pixel by attaching an active amplitude modulation display pixel to each of the petal patterns.

Claim 1:
An active complex spatial light modulation apparatus (<NUM>) for an ultra-low noise holographic display, the apparatus comprising:
a substrate (<NUM>); and
a petal antenna (<NUM>) comprising three petal patterns (<NUM>, <NUM>, <NUM>) arranged on the substrate (<NUM>), dividing a complex plane into three phase sections, and modulating the input light into three-phase amplitude values corresponding to the phase sections;
wherein the petal antenna (<NUM>) has a point symmetry shape based on a center point of the petal antenna (<NUM>),
wherein each of the petal patterns (<NUM>, <NUM>, <NUM>) comprises at least two petal elements arranged in a point symmetry form based on the center point;
wherein at least two of the petal elements are spaced apart from each other with the center point interposed between the spaced apart petal elements;
wherein a first petal pattern of the three petal patterns (<NUM>, <NUM>, <NUM>) represents the input light as a first amplitude value corresponding to a first phase section of the three phase sections,
wherein a second petal pattern of the three petal patterns represents (<NUM>, <NUM>, <NUM>) the input light as a second amplitude value corresponding to a second phase section of the three phase sections,
wherein a third petal pattern of the three petal patterns (<NUM>, <NUM>, <NUM>) represents the input light as a third amplitude value corresponding to the third phase section of the three phase sections, and
wherein the first amplitude value is determined based on the size of the first petal pattern, the second amplitude value is determined based on the size of the second petal pattern, and the third amplitude value is determined based on the size of the third petal pattern;
the apparatus further comprising, for each petal pattern (<NUM>, <NUM>, <NUM>), an element attached to the petal elements of the corresponding petal pattern (<NUM>, <NUM>, <NUM>), wherein the element is configured to actively modulate the amplitude of a light wave to the petal element.