Abstract: Provided is a holographic printer using a mechanical shutter having adjustable exposure time and no vibration. The holographic printer according to an embodiment of the present invention comprises: a light source; a modulator for generating a holographic fringe pattern in hogel units; a stage on which a hologram recording medium is placed; a driving part for moving the position of the stage in hogel units; and a shutter for periodically exposing an object light due to the holographic fringe pattern generated by the modulator to the hologram recording medium. The shutter comprises: a rotation plate having formed therein an arc-shaped opening which exposes the object light due to the holographic fringe pattern; and a motor for rotating the rotation plate. Therefore, the exposure period and exposure time of the shutter can be variously adjusted by adjusting the rotational state of the rotation plates having the arc-shaped opening formed therein.

Abstract: A holographic printer using a vibration-free mechanical shutter is provided. A holographic printer, according to an embodiment of the present invention, comprises: a light source which emits light; a modulator which modulates the light emitted from the light source to generate a holographic fringe pattern in a hogel unit; a stage on which a holographic recording medium, on which a holographic fringe pattern generated by the modulator is to be recorded in a hogel unit, is placed; a driving part which moves a position of the stage in a hogel unit; and a shutter which periodically exposes, to the holographic recording medium, object light generated by the holographic fringe pattern generated by the modulator, wherein the shutter includes a rotating plate having a slit that exposes the object light by means of the holographic fringe pattern, and a motor rotating the rotating plate.

Abstract: A method and a system for foveated hologram rendering are provided. A method for foveated hologram rendering according to an embodiment of the present invention comprises: tracking a user's line of sight, rendering a hologram having a first resolution in the user's central line of sight, and rendering a hologram having a resolution lower than the first resolution in the user's peripheral line of sight. Accordingly, a hologram content with high quality and high resolution can be generated and reproduced at high speed through foveated hologram rendering in which holograms having different resolutions are rendered in the user's central line of sight and peripheral line of sight.

Abstract: A hologram generation and streaming method and system using multi-PCs are provided. A hologram streaming service system according to an embodiment of the present invention comprises: a hologram generation server for generating a hologram streaming image by using multiple computers; and a hologram player for playing the hologram streaming image generated in the hologram generating server. Therefore, distributed processing of the multi-PCs is used to generate a hologram at high speed so that a service can be streamed without delay in real time even for a high-resolution hologram.

Abstract: The present invention relates to a carbon-supported and surface-engineered platinum nanocube catalyst having excellent ammonia oxidation activity, a method for preparing the same, and an ammonia decomposition device including the same.

Abstract: This invention relates to a system for measuring water quality using a smartphone, and more particularly to a system for measuring water quality using a smartphone, in which, to solve problems of hand-operated and manual water quality measurement methods and in order to increase reliability and accuracy, a water quality meter and a smartphone, which mutually communicate with each other, are utilized, and also, the smartphone is provided with a memory unit, a calculation unit, a GPS unit, etc., thus enabling water quality to be measured in real time and water quality data to be stored and transferred to the outside, so that reliability and accuracy of the measured water quality data may be improved.

Abstract: This invention relates to a system for measuring water quality using a smartphone, and more particularly to a system for measuring water quality using a smartphone, in which, to solve problems of hand-operated and manual water quality measurement methods and in order to increase reliability and accuracy, a water quality meter and a smartphone, which mutually communicate with each other, are utilized, and also, the smartphone is provided with a memory unit, a calculation unit, a GPS unit, etc., thus enabling water quality to be measured in real time and water quality data to be stored and transferred to the outside, so that reliability and accuracy of the measured water quality data may be improved.