Projection type image display apparatus

A projection type image display apparatus, comprising:

• a light source;
• a
• first polarization selective reflection element having a function of reflecting or transmitting a light beam from the light source in accordance with a polarization direction thereof;
• a first element for modulating a polarization plane of an incident light beam in accordance with an image to be displayed;
• a projection lens for projecting the modulated light beam;
• and
• polarizing filters for transmitting only a linearly polarized component of a light beam having one direction,
• wherein the polarization selective reflection element is film-like and has an optical transmission axis and an optical reflection axis,
• the polarization selective reflection element transmits a first linearly polarized light beam, and reflects a second linearly polarized light beam having a polarization plane orthogonal to a polarization plane of the first linearly polarized light beam, regardless of a direction of incidence of a light beam with respect to the polarization selective reflection element, and
• the polarizing filters including a first polarizing filter located between the light source and the polarization selective reflection element, and a second polarizing filter located between the polarization selective reflection element and the projection lens, the first and second polarizing filters being arranged in such a manner that the transmission axes thereof are in a crossed Nicols state with respect to the optical path.

A projection type image display apparatus, comprising:

• a light source;
• a polarization selective reflection element for transmitting light from said light source of one polarization and reflecting light from said light source of another polarization, said polarization selective reflection element transmitting the light having the one polarization as a first linearly polarized light beam parallel to a transmission axis thereof and reflecting the light having the other polarization as a second linearly polarized light beam parallel to a reflection axis thereof;
• a light modulating element for modulating a polarization of one of the first and second linearly polarized light beams in accordance with an image to be displayed;
• a projection lens for projecting the modulated light beam;
• and
• polarizing filters for transmitting only a linearly polarized component of a light beam having one direction, the polarizing filters including a first polarizing filter located between the light source and the polarization selective reflection element, and a second polarizing filter located between the polarization selective reflection element and the projection lens, the first and second polarizing filters being arranged in such a manner that the transmission axes thereof are in a crossed Nicols state with respect to the optical path.

A projection type image display apparatus, comprising:

• a light source;
• a plurality of a polarization selective reflection elements each for transmitting light from said light source of one polarization and reflecting light from said light source of another polarization, each said polarization selective reflection element transmitting the light having the one polarization as a first linearly polarized light beam parallel to a transmission axis thereof and reflecting the light having the other polarization as a second linearly polarized light beam parallel to a reflection axis thereof;
• light modulating elements, each light modulating element modulating a polarization plane of one of the first and second linearly polarized light beams of a corresponding one of said polarization selective reflection elements in accordance with an image to be displayed;
• a synthesizing element for synthesizing the light beams modulated by said light modulating elements;
• a projection lens for projecting the synthesized modulated light, and polarizing filters arranged in the light paths between said light source and each of said polarization selective reflection elements.

A projection type image display apparatus, comprising:

• a light source;
• a plurality of a polarization selective reflection elements each for transmitting light from said light source of one polarization and reflecting light from said light source of another polarization, each said polarization selective reflection element transmitting the light having the one polarization as a first linearly polarized light beam parallel to a transmission axis thereof and reflecting the light having the other polarization as a second linearly polarized light beam parallel to a reflection axis thereof;
• light modulating elements, each light modulating element modulating a polarization plane of one of the first and second linearly polarized light beams of a corresponding one of said polarization selective reflection elements in accordance with an image to be displayed;
• a synthesizing element for synthesizing the light beams modulated by said light modulating elements;
• a projection lens for projecting the synthesized modulated light;
• and
• polarizing filters for transmitting only a linearly polarized component of a light beam having one direction, the polarizing filters including first polarizing filters each of which is located between the light source and one of the polarization selective reflection elements, and second polarizing filters each of which is located between one of the polarization selective reflection elements and the projection lens, the first and second polarizing filters being arranged in such a manner that the transmission axes of respective pairs of first and second polarizing filters are in a crossed Nicols state with respect to the optical path.

A projection type image display apparatus, comprising:

• a light source;
• a first polarization selective reflection element having a function of reflecting or transmitting a light beam from the light source in accordance with a polarization direction thereof;
• a first element for modulating a polarization plane of an incident light beam in accordance with an image to be displayed;
• and
• a projection lens for projecting the modulated light beam,
• wherein the first polarization selective reflection element is film-like and has an optical transmission axis and an optical reflection axis,
• the first polarization selective reflection element transmits a first linearly polarized light beam, and reflects a second linearly polarized light beam having a polarization plane orthogonal to a polarization plane of the first linearly polarized light beam, regardless of a direction of incidence of a light beam with respect to the first polarization selective reflection element, wherein
• the first element is one of a plurality of elements,
• the apparatus further comprises in addition to the first polarization selective reflection element, a second polarization selective reflection element between the projection lens and the plurality of elements,
• light beams which have been reflected or transmitted by the first polarization selective reflection element and which have been modulated by the plurality of elements are synthesized by the second polarization selective reflection element to form a synthesized light beam, the light beams reflected or transmitted by the first polarization selective reflection element corresponding to the plurality of image display elements, respectively, and
• the synthesized light beam is incident upon the projection lens.