| 摘要 |
PURPOSE:To provide a projection type image display device which can provide illuminating light having good parallelism and a uniform illuminance distribution and can provide a uniform, bright screen of high picture quality while reducing the ununiformity of contrasts due to photoelasticity and restraining generation of color unevenness. CONSTITUTION:The form of a correcting lens 3 is designed following the Snell's law so that of rays of light reflected by a reflecting mirror 2 those which are not parallel to the optical axis 9 of a lighting system are refracted and made parallel to the optical axis 9. Illuminating light from the lighting system is therefore good at parallelism. Even when the relative positions of a light source 1 and the reflecting mirror 2 are adjusted so that the illuminating light is not extracted, the rays of light whose parallelism is made worse by deviating of the positions are made parallel by the correcting lens 3, so that the ununiformity of the illuminance of the illuminating light is improved without deteriorating the parallelism. |
