Projection type display apparatus with increased life of optical constituent components

A projection type display apparatus, comprising:

• a light source;
• a display element;
• an illumination optical system comprising a plurality of optical elements to enter light from the light source and to emit the light to the display element;
• and
• a projection lens to magnify an optical image formed by the display element and to project a magnified image of the optical image,
• wherein the illumination optical system comprises:
• a first array lens and a second array lens each includes a plurality of lens elements arranged in a matrix, each of the lens elements having a rectangular shape opening and
• a polarization conversion element having a polarization conversion function to convert a polarization direction of light incident thereon into a predetermined polarization direction of light and to emit polarized light by use of a plurality of polarized beam splitters and a plurality of half-wave phase plates, the beam splitters and the phase plates being arranged in an array and opposing to the lens elements of the second array lens, and
• wherein the light source comprises a light emitting plane having substantially a rectangle or an ellipse shape, and
• wherein a vertical direction of the shape of the light emitting plane is substantially parallel to the predetermined direction, and a longitudinal direction of the shape of the light emitting plane is substantially parallel to a longitudinal direction of an opening of the polarization conversion element.