Abstract: An optical device includes a gallium arsenide (GaAs) substrate, and a multiple quantum well structure formed on the GaAs substrate and having a quantum well layer and a quantum barrier layer. In the optical device, the quantum well layer is formed of a first semiconductor material that has a bandgap energy which is lower than that of the GaAs substrate and receives a compressive strain from the GaAs substrate, and the quantum barrier layer is formed of a second semiconductor material that has a bandgap energy which is higher than that of the GaAs substrate and receives a tensile strain from the GaAs substrate.

Abstract: A transmissive light modulator including a first reflection layer; a first active layer, arranged on the first reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; a second reflection layer arranged on the first active layer; a second active layer, arranged on the second reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; and a third reflection layer arranged on the second active layer, wherein the first reflection layer and the third reflection layer are each doped with a first type dopant, and the second reflection layer is doped with a second type dopant, which is electrically opposite to the first type dopant.

Abstract: Provided are a wavelength separation device and a 3-dimensional (3D) image acquisition apparatus including the same. The wavelength separation device includes a first prism having an inclined surface and a second prism bonded to a first region of the inclined surface of the first prism. A wavelength separation coating may be disposed at a junction between the first portion of the inclined surface of the first prism and the second prism, and a second portion of the inclined surface of the first prism, different from the first portion, is a total reflection surface that totally internally reflects light.

Abstract: A transmissive image modulator for allowing image modulation over a wide bandwidth with multiple Fabry-Perot resonant modes and multiple absorption modes is provided. The transmissive image modulator includes a lower reflection layer; an active layer disposed on the lower reflection layer, including multiple quantum well layers and multiple barrier layers; an upper reflection layer disposed on the active layer; and at least one micro-cavity layer disposed in at least one of the lower and upper reflection layer. The active layer and the at least one micro-cavity layer have thicknesses of a multiple of ?/2, where ? is a resonant wavelength.

Abstract: A 3 dimensional (3D) image acquisition apparatus and a method of extracting depth information in the 3D image acquisition apparatus are provided. The method of extracting depth information includes sequentially projecting N (N is a natural number equal to or greater than 3) different pieces of projection light onto a object; modulating N pieces of reflection light reflected from the object with an optical modulation signal having a gain waveform; generating N images by capturing the N pieces of modulated reflection light; generating a first averaged image by multiplying the N images by primary weights and generating a second averaged image by multiplying the N images by secondary weights; acquiring an average phase delay from the first and second averaged images; and calculating a distance to the object from the average phase delay.

Abstract: Provided is a 3-dimensional (3D) image acquisition apparatus and a method of driving the same. The 3D image acquisition apparatus includes a light source, an optical shutter, an image sensor, an image signal processor, and a controller. The light source is configured to project illumination light on an object. The optical shutter is configured to modulate the illumination light reflected from the object with a predetermined gain waveform. The image sensor is configured to generate a depth image by detecting the illumination light modulated by the optical shutter. The image signal processor is configured to calculate a distance from the 3D image acquisition apparatus to the object using the depth image generated by the image sensor. The controller is configured to control an operation of the light source and an operation of the optical shutter.

Abstract: An imaging optical system and a three-dimensional (3D) image acquisition apparatus which includes the imaging optical system are provided. The imaging optical system includes an object lens configured to transmit light; first and second image sensors having different sizes from each other; a beamsplitter on which the light transmitted by the object lens is incident, the beamsplitter being configured to split the light incident thereon into light of a first wavelength band and light of a second wavelength band, and to direct the light of the first wavelength band to the first image sensor and the light of the second wavelength band to the second image sensor; and at least one optical element, disposed between the beamsplitter and the second image sensor, configured to reduce an image that is incident on the second image sensor, the optical element including at least one of a Fresnel lens and a diffractive optical element.

Abstract: An imaging optical system includes an objective lens configured to focus light having a first wavelength band and light having a second wavelength band, an optical shutter module configured to reflect the light having the first wavelength band, which is focused by the objective lens, without modulating the light having the first wavelength band and to modulate the light having the second wavelength band, which is focused by the objective lens, and reflect the modulated light having the second wavelength band, and an image sensor configured to respectively sense the light having the first wavelength band and the modulated light having the second wavelength band, which are reflected by the optical shutter module, and to output a first image signal with respect to the light having the first wavelength band and a second image signal with respect to the modulated light having the second wavelength band.

Abstract: A 3-dimensional (3D) image acquisition apparatus capable of simultaneously obtaining a color image and a depth image in a single shooting operation is provided. The apparatus includes a light source for radiating illumination light having a predetermined wavelength onto an object; a lens unit having at least four object lenses; an image sensor including at least four sensing regions for individually receiving light focused by the object lenses and for generating images; and at least three optical shutters individually facing at least three of the at least four object lenses and for modulating incident light with predetermined gain waveforms.

Abstract: A method and apparatus for determining a distance between an optical apparatus and an object by considering a measured nonlinear waveform, as opposed to a mathematically ideal waveform. The method and apparatus may accurately calculate distance information without being affected by a type of waveform projected onto the object and may not require an expensive light source or a light modulator for generating a light with little distortion and nonlinearity. Further, since the method may be able to use a general light source, a general light modulator, and a general optical apparatus, additional costs do not arise. Furthermore, a lookup table, in which previously calculated distance information is stored, may be used, and thus the amount of computation required to be performed to calculate the distance is small, thereby allowing for quick calculation of the distance information in real time.

Abstract: A large-area transmissive type optical image modulator, a method of manufacturing the same, and an optical apparatus including the transmissive type optical image modulator are provided. The large-area transmissive type optical image modulator includes: a base substrate; a first expitaxial layer formed on the base substrate; a second expitaxial layer formed on the first expitaxial layer; a first electrode formed on the first expitaxial layer and spaced apart from the second expitaxial layer; a second electrode formed on the second expitaxial layer; and a transparent substrate covering the second expitaxial layer and the second electrode, wherein the base substrate includes a through hole corresponding to a light emitting area, and the first expitaxial layer may include an n-type or p-type doping material.

Abstract: A transmissive light modulator including a first reflection layer; a first active layer, arranged on the first reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; a second reflection layer arranged on the first active layer; a second active layer, arranged on the second reflection layer and including a plurality of quantum well layers and a plurality of barrier layers; and a third reflection layer arranged on the second active layer, wherein the first reflection layer and the third reflection layer are each doped with a first type dopant, and the second reflection layer is doped with a second type dopant, which is electrically opposite to the first type dopant.

Abstract: A 3-dimensional (3D) image acquisition apparatus and a method of calculating depth information in the 3D image acquisition apparatus, the 3D image acquisition apparatus including: an optical modulator for modulating light reflected from a subject by sequentially projected N (N is 3 or a larger natural number) light beams; an image sensor for generating N sub-images by capturing the light modulated by the optical modulator; and a signal processor for calculating depth information regarding a distance to the subject by using the N sub-images.

Abstract: A three-dimensional (3D) image acquisition apparatus is provided. The 3D image acquisition apparatus includes: an interchangeable lens unit comprising a lighting unit that irradiates light toward an object, a color image lens unit that forms a color image of the object, and a depth image capturing unit that comprises a depth image lens unit for obtaining depth image information relating to the object; and a main body comprising a first image sensor that converts an optical image formed by the color image lens unit into an electric signal and an image processor that forms a 3D image using the electric signal of the first image sensor and depth information of the depth image capturing unit, wherein the interchangeable lens unit is detachable from the main body.

Abstract: A photonic crystal type light modulator is provided. The photonic crystal type light modulator includes: a substrate; a first electrode disposed on the substrate; an active layer disposed on the first electrode, where an optical characteristic of the active layer changes according to application of an electric field; a second electrode disposed on the active layer; and a photonic crystal layer disposed on the second electrode and comprising a 2D grating.

Abstract: A 3 dimensional (3D) image acquisition apparatus and a method of extracting depth information in the 3D image acquisition apparatus are provided. The method of extracting depth information includes sequentially projecting N (N is a natural number equal to or greater than 3) different pieces of projection light onto a object; modulating N pieces of reflection light reflected from the object with an optical modulation signal having a gain waveform; generating N images by capturing the N pieces of modulated reflection light; generating a first averaged image by multiplying the N images by primary weights and generating a second averaged image by multiplying the N images by secondary weights; acquiring an average phase delay from the first and second averaged images; and calculating a distance to the object from the average phase delay.

Abstract: An illumination optical system of a 3-dimensional (3D) image acquisition apparatus and a 3D image acquisition apparatus including the illumination optical system. The illumination optical system of a 3D image acquisition apparatus includes a beam shaping element which outputs light having a predetermined cross-sectional shape which is proportional to a field of view of the 3D image acquisition apparatus. The beam shaping element may adjust a shape of illumination light according to its cross-sectional shape. The beam shaping element may uniformly homogenize the illumination light without causing light scattering or absorption.

Abstract: An optical system including integrated illumination and imaging optical systems, and a 3-dimensional (3D) image acquisition apparatus including the optical system. In the optical system of the 3D image acquisition apparatus, the illumination optical system and the imaging optical system are integrated to have a coaxial optical path. Accordingly, there is no parallax between the illumination optical system and the imaging optical system, so that depth information about an object acquired using illumination light may reflect actual distances between the object and the 3D image acquisition apparatus. Consequently, the depth information about the object may be more precise. The zero parallax between the illumination optical system and the imaging optical system may improve utilization efficiency of the illumination light. As a result, a greater amount of light may be incident on the 3D image acquisition apparatus, which ensures to acquire further precise depth information about the object.

Abstract: A beam splitter and a 3D image acquisition apparatus including the beam splitter are provided. The beam splitter includes a light incident surface on which light having a first wavelength and light having a second wavelength are incident; a beam splitting surface which is inclined to the light incident surface and reflects the light having the first wavelength and transmits the light having the second wavelength; a first light exit surface through which the light having the first wavelength reflected from the beam splitting surface exits; a first reflective surface which reflects the light having the second wavelength transmitted by the beam splitting surface; a second reflective surface which reflects the light having the second wavelength reflected from the first reflective surface; and a second light exit surface through which the light having the second wavelength reflected from the second reflective surface exits.

Abstract: A method and apparatus for determining a distance between an optical apparatus and an object by considering a measured nonlinear waveform, as opposed to a mathematically ideal waveform. The method and apparatus may accurately calculate distance information without being affected by a type of waveform projected onto the object and may not require an expensive light source or a light modulator for generating a light with little distortion and nonlinearity. Further, since the method may be able to use a general light source, a general light modulator, and a general optical apparatus, additional costs do not arise. Furthermore, a lookup table, in which previously calculated distance information is stored, may be used, and thus the amount of computation required to be performed to calculate the distance is small, thereby allowing for quick calculation of the distance information in real time.