Baku Katagiri

Speckle reduction mechanism in laser rear projection displays using a small moving diffuser.

Recently, a practical method of speckle reduction in laser rear projection displays that uses an optical system with a small moving diffuser has attracted much attention. In this paper, a model of the speckle generation and reduction mechanism in the system is presented. We investigated the speckle, focusing on the physical aspects of its generation, rather than treating it statistically. We found that the granularity of the speckle patterns generated by the small diffuser corresponded to the size of the coherent regions on the projection screen. This determined the efficiency of the speckle reduction when the small diffuser was rotated.

Multiple directional viewing projection display based on the incident-angle-independent, diffusion-angle-quantizing technology

We have devised an incident-angle-independent, quantized-diffusion-angle screen and have realized a multiple directional viewing projection display system using double-side lenticular lens. Our display system has advantages of easy alignment for multiple projectors, and capability of multiple different images simultaneously according to viewing angle at any distance from the screen.

Novel screen technology for high-contrast front-projection display by controlling ambient-light reflection

One problem with front-projection displays is that the screen contrast ratio decreases in bright ambient light. In this paper, we propose a new front-projection display system that incorporates the control of reflection of ambient light in the screen design, providing a high contrast ratio even in a brightly lit room.

A high‐contrast front‐projection display system optimizing the projected light‐angle range

— The problem with front-projection displays is that the screen contrast ratio decreases under bright-ambient conditions. To overcome this problem, the design of a special screen, composed of the diffuser whose diffusing property shows top-hat characteristics and a sawtooth reflector, is proposed. The screen diffuses the incident image light arriving at a projection-angle range that is a lower-angle range than the viewing-angle range, and reflects the ambient light out of the viewing-angle range. In this paper, the projection-angle range and the viewing-angle range was optimized to improve the contrast ratio of a front-projection display. As a result, a special screen with the above-mentioned diffusing property was realized, and a high-quality front-projection display with a high contrast ratio, even in a bright room, was achieved.

High-Resolution Multi-View Projection Display With a Quantized-Diffusion-Angle Screen

In this paper, we have devised a novel projection screen using a double-sided lenticular lens with a diffusion angle range quantized by the incident light angle and a constant diffusion light intensity, independent of the angle of the incident light. We developed high-resolution multi-view projection display using a novel projection screen and multiple projectors. Our display system has the advantage of making it easy to align multiple projectors, and the capability of simultaneously projecting multiple different images at different viewing angles at any distance from the projection screen.

Double-layer anisotropic light diffusion films fabricated using a two-step UV curing technique

We developed a novel light diffusion film with a double diffusion layer structure for high reflectivity and a wide diffusion angle range. We demonstrated that the internal layer structure of the light diffusion film is controlled by the diffusion angle of the ultraviolet (UV) light used for photopolymerization. We successfully fabricated two different diffusion layers in a single polymer film using a two-step UV curing process and achieved a wide diffusion angle range and high reflectivity normal to the film surface. Our light diffusion film can control the distribution of diffused light, and should contribute to the development of future low-power reflective displays with high reflectivity similar to the white paper.

High‐contrast front‐projection system for large‐screen displays suppressing reflection and diffusion of ambient light

— A new front-projection system for large screens by diffusing only projected light to wards the viewing-angle range and reflecting ambient light towards the other angle ranges is proposed. With this system, a high-quality and large-sized front-projection display with a high contrast ratio even in a bright room has been realized.

8.3: High‐Contrast in Bright Ambients with Angle‐Shifting Front Projection Screen

We have proposed a screen, which can diffuse incident light from the projector set in lower angle range to viewing angle range and can reflect ambient light to angle range out of viewing. with this control, the screen realizes a clear image even in a bright room.

An initial examination of multi-view display using QDA screens for teleconference systems

Our novel multi-view display is based on the “Quantized-Diffusion-Angle screen (QSA Screen).” We believe that the multi-view screen brings high tele-presence to teleconference systems because it accurately reproduces head direction, one of the essential modalities for teleconference systems. This paper proposes a short projection method to eliminate the weakness of the QDA screen when applied to teleconference systems and provides and initial examination.

73.1L: Late‐News Paper: Novel Multi‐View Display using QDA Screen with Short Projection Distance by Tiled Image Method

We have developed a novel multi-view display that uses “Quantized-Diffusion-Angle screen (QDA Screen).” In this paper, we propose a tiled image method to eliminate the need for a QDA screen with long projection distance.