Takizawa K, Fujii T, Fujikake H, Hirabayashi T, Tanaka Y, Hara K, Takano S, Asakawa H, Kita H
Science and Technical Research Laboratories, Japan Broadcasting Corporation, 1-10-11 Kinuta, Setagaya-ku, Tokyo 157-8510, Japan.
Appl Opt. 1999 Apr 20;38(12):2570-8. doi: 10.1364/ao.38.002570.
We made a liquid-crystal (LC) luminaire for the first time to our knowledge by combining a metal halide lamp and an optical shutter composed of a compound of a very high nematic-isotropic point (172 degrees C) LC and a polymer (CLCP). The shutter can modulate high-power light independently of the state of polarization because the CLCP film becomes transparent or opalescent when either sufficiently high or no voltage is applied to it. To solve the problem, which is peculiar to CLCP films, that the color temperature of light modulated by the film changes with the film's transmittance, a pulse-width modulation method that varies the time ratio of the on and off states of the shutter was developed. The performance characteristics of the luminaire were as follows: illuminance range, 192 to 10,400 lx at a distance of 5 m from the luminaire; rise and decay times, 1.4 and 1.5 ms; color temperature, 4060-5600 K; operation room temperature, approximately 150 degrees C; stable operation time, more than 2000 h. Experimental results show the feasibility of applications of this luminaire in various fields, including television, movie, and stage lighting.
据我们所知，我们首次通过将金属卤化物灯与由具有非常高的向列相-各向同性转变温度（172℃）的液晶化合物和聚合物组成的光学快门相结合，制成了一种液晶（LC）灯具。该快门可以独立于偏振状态调制高功率光，因为当向其施加足够高的电压或不施加电压时，胆甾相液晶聚合物（CLCP）薄膜会变得透明或呈乳白色。为了解决CLCP薄膜特有的问题，即由该薄膜调制的光的色温会随薄膜的透射率而变化，我们开发了一种改变快门开和关状态的时间比的脉宽调制方法。该灯具的性能特点如下：照度范围，在距离灯具5米处为192至10400勒克斯；上升和衰减时间，分别为1.4毫秒和1.5毫秒；色温，4060 - 5600K；工作室温，约150℃；稳定工作时间，超过2000小时。实验结果表明，这种灯具在包括电视、电影和舞台照明在内的各个领域都具有应用的可行性。
