Polarized-light converting unit and projector using the same

A projector comprising:

• a light source unit which irradiates white light;
• a plurality of reflection type light bulbs which modulate an illumination light bundle emitted from the light source unit;
• color separation/synthesis unit which separates color light for the reflection type light bulbs from the illumination light bundle and combines the color light after the reflection thereof by the reflection type light bulbs;
• a projection lens which projectes images on the reflection type light bulbs;
• color separating unit, placed in an optical path between the light source unit and the color separation/synthesis unit, which separates the white light emitted from the light source unit into two types of color light of a specific wavelength band thereof and the remaining wavelength band thereof;
• and
• a first polarizing beam splitter and a second polarizing beam splitter on which the two types of color light separated by said color separating means are respectively incident from different incident planes, and which are joined in a columned form or shaped in an integrated prism form;
• wherein said first polarizing beam splitter includes two incident planes on which the two types of color light separated into the color light of the specific wavelength band from the white light and the color light of the remaining wavelength band thereof from the while light are respectively incident, and
• said second polarizing beam splitter is provided with both a first ¼-wave plate and a first dichroic mirror, and a second ¼-wave plate and a second dichroic mirror different in wavelength characteristic from the first dichroic mirror, both of which are respectively disposed on two adjacent surfaces different from a junction surface with said first polarizing beam splitter and an outgoing surface thereof.