| 摘要 |
PURPOSE:To use a liquid crystal optical element for a projection type display and to commonly use the element as a rear surface projection type and a front surface projection type by constituting the liquid crystal optical element in such a manner that the element can be changed over to a light scattering state and a transparent state having concave and convex lens functions at need. CONSTITUTION:The liquid crystal optical element 1 can be changed over to the light scattering state and the transparent state having the concave and convex lens functions by changing over the light scattering state and transparent state of a liquid crystal 4 by an electrooptical effect or thermooptical effect. The lens function of the lenticular lens 3a is controlled by changing the refractive index of the liquid crystal 4 by the electrooptical effect or thermooptical effect, by which the element can be changed over to the light scattering state and the transparent state. Further, the lens function of the Fresnel lens 2a and the lens function of the lenticular lens 3a are alternately exhibited by changing the refractive index of the liquid crystal 4 by the electrooptical effect or thermooptical effect, by which the element is changed over to the light scattering state and the transparent state having the concave and convex lens functions. |
