• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2000.11a
• /
• pp.60-63
• /
• 2000

In this study, efficient force reflection algorithm is developed for the Haptic Display by using a proxy concept and friction model. When there are not any contacted obstacles the proxy is following human operator's command trajectory in the 3D virtual space. But when the operator's command trajectory is locating inside of the object, the proxy is constrained by the surface of the object. Here only with the information of the proxy position and operator's command trajectory at every time step, we can calculate the reflection force and its orientation. To display the friction force between two virtual stiff material which are sliding against each other, modified Karnopp's friction model is used. In the friction model, a damping term and a Stribeck effect term are included to display the relative velocity effect and stick-slip effect at the very low relative velocity region respectively.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07b
• /
• pp.1171-1174
• /
• 2005

This thesis provides a new digital convergence method and apparatus which uses area photo sensor and new analog to digital algorithmic to identify the correct digital pattern position factor of the projection system. This method and apparatus can be applied to the convergence correction in a TV receiver with a display that comprises a display screen with photo sensors positioned adjacent to screen edges. It also can be applied to the manufacture process detection of the projection system to adjust the associative convergence parameter. In this paper, demonstrate how this convergence detecting algorithmic was implemented with four area photo sensors of special designed pattern to the rear projection CRT TV.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2005.07a
• /
• pp.793-796
• /
• 2005

A structure and a design of device were developed to fabricate large-scale active matrix organic light-emitting diode (AMOLED) display with good color purity and high aperture ratio. With these technologies, we developed a full color 14.1 inch WXGA AMOLED display. For the integration of OLED on an active matrix a-Si TFT backplane, an efficient top emission OLED is essential since the TFT circuitry covers a large position of the pixel aperture. These technologies will enable up the OLED applications to larger size displays such as desktop monitors and TVs.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.1341-1344
• /
• 2009

A novel method to control the viewing direction by moving aperture location in 4-f illumination optics to control light direction is proposed. Based on integral imaging principle, the relayed point light sources by 4-f optics are modulated by a spatial light modulator, displaying three-dimensional images. In the proposed method, we locate the aperture, which acts as a band pass filter, around an optic axis to control the light direction. Resultantly, assuming that we know the viewer position by a tracking system, we can display appropriate three-dimensional images over large viewing angle.

• Journal of Platform Technology
• /
• v.6 no.4
• /
• pp.3-10
• /
• 2018

A projection-based active information display system was proposed. The proposed system is based on Intelligent Space and a steerable projector mounted mobile robot which is called Ubiquitous Display (UD). In order to transfer visual information for a human in the Intelligent Space, the UD projects a certain shape of an image with a fixed size. Due to redundancy of degree of freedom (DOF), there are lots of situations to project a same shape and size of the image on a surface. In this paper, we describe a method to determine a goal posture of the UD. Here, the goal posture is the most efficient position and orientation of the UD so as to project visual information and it is determined by the Intelligent Space. To verify the proposed method, simulation and demonstration are carried out.

• Proceedings of the IEEK Conference
• /
• 2000.11d
• /
• pp.231-234
• /
• 2000

This paper has been studied a method that effectively displaying color image to monochromatic display such as PDA and movable-phone. Generally, the Floyd-Steinberg dithering algorithm has been used in this area and its' effectiveness were well known. But it shows some ugly patterns in white area and also shows some directionality in vertical and horizontal directions. To reduce those directionality, I suggest the error diffusion direction to be rotated randomly according to the bit value of the current position. This can also mitigate some ugly pattern in white area

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2005.05a
• /
• pp.125-128
• /
• 2005

The equipments in semi-conductor, display and measurement fields require high precision and resolution positioning technology. High positioning control can be carried out by using linear motors with little vibration, backlash and friction. In this paper, the acceleration patterns of the moving Part are analyzed to obtain the optimum pattern which leads to the less vibration reduction of equipment. In addition, the effect of friction force in guide rail on position control accuracy is investigated to identify possibility of using current bearing system for nano-positioning control.

• Journal of Information Display
• /
• v.2 no.4
• /
• pp.19-22
• /
• 2001

In this paper, we describe the electro-optic effects of photonic crystals made of a synthetic opal filled with a nematic liquid crystal(LC). By applying an external electric field, a shift in the Bragg reflection peak position(stop band) and a field-induced change in its peak reflectivity are observed. These significant surface alignment effects of the opal-LC composite are discussed in a similar manner for Freederick-type transitions of LC within a confined geometry in the presence of external fields.

• Journal of the Semiconductor & Display Technology
• /
• v.21 no.3
• /
• pp.12-16
• /
• 2022

In this paper, a method for measuring image pattern widths is proposed using gaussian interpolation, in order to improve inconsistent results coming from the different directions in image patterns. The performance of our method is evaluated using image patterns with 9 directions, and compared with previous methods. It is confirmed that the proposed method gives accurate and consistent width results regardless of pattern directions.

• Journal of Drive and Control
• /
• v.13 no.1
• /
• pp.49-53
• /
• 2016

The accurate calculation of bucket tip position has a large influence on showing the motion of an excavator on the display device of the excavator and controlling the excavator automatically. It is generally known that Inertial Measurement Unit (IMU) sensors are more accurate than accelerometer-based sensors while the boom, arm or bucket moves because additional forces beyond gravity add additional acceleration to the sensors. To prove the accuracy difference between the two types of sensors, a position recognition system using an accelerometer-based sensor and an IMU sensor is implemented on the excavator. The experimental results show that the system using the IMU sensor significantly reduces the position recognition error while bucket moves and additional force beyond gravity exists.