Projection apparatus

A projection apparatus comprising:

• a color synthesis section configured to combine three-primary color light and emit combined light,
• a polarization conversion section disposed on a light-emission side of the color synthesis section, the polarization conversion section being configured to put the color light in the combined light in a non-polarized state uniformly in all directions and including any one of a wavelength-selective half waveplate, a uniaxial organic material, and a uniaxial crystal, the wavelength-selective half waveplate producing a phase shift of π with respect to light with a predetermined wavelength, the uniaxial organic material being an organic material having one optical axis, the uniaxial crystal being a crystal having one optical axis;
• and
• a projection lens configured to emit light provided by the polarization conversion section, wherein
• the color synthesis section includes
• a color synthesis prism,
• a half waveplate disposed on a light-incident side of the color synthesis prism where green light enters, and
• a quarter waveplate disposed between a light-incident side of the polarization conversion section and a light-emission side of the color synthesis prism,
• the half waveplate converts S-polarized green light into P-polarized green light,
• the color synthesis prism combines red S-polarized light being S-polarized red light, green P-polarized light being the P-polarized green light, and blue S-polarized light being S-polarized blue light,
• the quarter waveplate converts the red S-polarized light into red left-handed circularly-polarized light being left-handed circularly-polarized light, the green P-polarized light into green right-handed circularly-polarized light being right-handed circularly-polarized light, and the blue S-polarized light into blue left-handed circularly-polarized light being left-handed circularly-polarized light, and
• the polarization conversion section puts each of the red left-handed circularly-polarized light, the green right-handed circularly-polarized light, and the blue left-handed circularly-polarized light in the non-polarized state.

A projection apparatus according comprising:

• a color synthesis section configured to combine three-primary color light and emit combined light,
• a polarization conversion section disposed on a light-emission side of the color synthesis section, the polarization conversion section being configured to put the color light in the combined light in a non-polarized state uniformly in all directions and including any one of a wavelength-selective half waveplate, a uniaxial organic material, and a uniaxial crystal, the wavelength-selective half waveplate producing a phase shift of π with respect to light with a predetermined wavelength, the uniaxial organic material being an organic material having one optical axis, the uniaxial crystal being a crystal having one optical axis;
• and
• a projection lens configured to emit light provided by the polarization conversion section, wherein
• the color synthesis section includes
• a color synthesis prism, and
• a quarter waveplate disposed between a light-incident side of the polarization conversion section and a light-emission side of the color synthesis prism,
• the color synthesis prism combines red S-polarized light being S-polarized red light, green S-polarized light being S-polarized green light, and blue S-polarized light being S-polarized blue light,
• the quarter waveplate converts the red S-polarized light into red left-handed circularly-polarized light being left-handed circularly-polarized light, the green S-polarized light into green left-handed circularly-polarized light being left-handed circularly-polarized light, and the blue S-polarized light into blue left-handed circularly-polarized light being left-handed circularly-polarized light, and
• the polarization conversion section puts each of the red left-handed circularly-polarized light, the green left-handed circularly-polarized light, and the blue left-handed circularly-polarized light in the non-polarized state.