A liquid crystal display device of a projection type, comprising: a light source, optical components being constructed as a transmission type of transmitting and projecting light from the light source, the optical components including - a liquid crystal panel, - a lens (4; 26), and - a polarizer (6, 7) having a polarizer film and a retaining plate for retaining the polarizer film, wherein at least any one of the lens (4; 26) and retaining plate is comprised of a sapphire substrate, and wherein light from the light source is transmitted through the lens (4; 26), the polarizer (6, 7) and the liquid crystal panel so as to be projected, wherein the liquid crystal panel includes a first and a second sapphire substrate used as a pair of transparent substrates facing each other with a liquid crystal layer sandwiched therebetween, pixels which are arranged in a matrix on the first sapphire substrate, and a transparent electrode formed on the second sapphire substrate characterized in that the primary plane of the first and the primary plane of the second sapphire substrate is any one of an R-plane, an A-plane, an M-plane and a Plane, the first sapphire substrate and the second sapphire substrate face each other so that each specific crystal axis thereof substantially coincides with a polarization transmission axis of polarized light to be transmitted, the pixels are arranged so as to be aligned with the specific crystal axis direction of the first sapphire substrate; the liquid crystal panel further includes: a vertical scanning circuit and a horizontal scanning circuit which are formed with the use of a thin film transistor comprised of silicon made by epitaxial growth on the first sapphire substrate, and send a video signal to the pixels. a light source, optical components being constructed as a transmission type of transmitting and projecting light from the light source, the optical components including - a liquid crystal panel, - a lens (4; 26), and - a polarizer (6, 7) having a polarizer film and a retaining plate for retaining the polarizer film, - a liquid crystal panel, - a lens (4; 26), and - a polarizer (6, 7) having a polarizer film and a retaining plate for retaining the polarizer film, wherein at least any one of the lens (4; 26) and retaining plate is comprised of a sapphire substrate, and wherein light from the light source is transmitted through the lens (4; 26), the polarizer (6, 7) and the liquid crystal panel so as to be projected, wherein the liquid crystal panel includes a first and a second sapphire substrate used as a pair of transparent substrates facing each other with a liquid crystal layer sandwiched therebetween, pixels which are arranged in a matrix on the first sapphire substrate, and a transparent electrode formed on the second sapphire substrate characterized in that the primary plane of the first and the primary plane of the second sapphire substrate is any one of an R-plane, an A-plane, an M-plane and a Plane, the first sapphire substrate and the second sapphire substrate face each other so that each specific crystal axis thereof substantially coincides with a polarization transmission axis of polarized light to be transmitted, the pixels are arranged so as to be aligned with the specific crystal axis direction of the first sapphire substrate; the liquid crystal panel further includes: a vertical scanning circuit and a horizontal scanning circuit which are formed with the use of a thin film transistor comprised of silicon made by epitaxial growth on the first sapphire substrate, and send a video signal to the pixels. a vertical scanning circuit and a horizontal scanning circuit which are formed with the use of a thin film transistor comprised of silicon made by epitaxial growth on the first sapphire substrate, and send a video signal to the pixels.