Optical apparatus, image display apparatus, and display apparatus

An optical apparatus into which light emitted from an image forming apparatus enters, in which the light is guided, and from which the light is emitted, the optical apparatus comprising:

• a light guide plate in which the light propagates by total reflection and from which the incident light is emitted;
• first deflection means adapted to deflect the light entering into the light guide plate in such a manner that the light is totally reflected in the light guide plate;
• second deflection means adapted to deflect the light that has propagated in the light guide plate by total reflection in such a manner as to cause the light to be emitted from the light guide plate;
• and
• third deflection means adapted to deflect the light that has been deflected by the first deflection means and that has propagated in the light guide plate by total reflection toward the second deflection means, wherein
• an incident angle of a central incident light beam that includes a light beam emitted from a center point of an image forming region of the image forming apparatus on the light guide plate, is an angle other than zero degrees, and
• a unit vector of the central incident light beam and a unit vector of a central outgoing light beam that include a light beam at a time of emission of the central incident light beam from the light guide plate, are identical in magnitude.

An image display apparatus, comprising:

• an image forming apparatus;
• and
• an optical apparatus into which light emitted from the image forming apparatus enters, in which the light is guided, and from which the light is emitted,
• the optical apparatus includes
• a light guide plate in which the light propagates by total reflection and from which the incident light is emitted,
• first deflection means adapted to deflect the light entering into the light guide plate in such a manner that the light is totally reflected in the light guide plate,
• second deflection means adapted to deflect the light that has propagated in the light guide plate by total reflection in such a manner as to cause the light to be emitted from the light guide plate, and
• third deflection means adapted to deflect the light that has been deflected by the first deflection means and that has propagated in the light guide plate by total reflection toward the second deflection means, wherein
• when first coordinate system is assumed, in the first coordinate system, a point where a normal line of the light guide plate passing through a center point of the first deflection means intersects the light guide plate is denoted as a first origin Oin, a normal line of the light guide plate passing through the first origin Oin and extending toward a side where the light is emitted from the light guide plate is denoted as a −Zin axis, and an axis parallel to a traveling direction of the light that is deflected by the first deflection means and propagates in the light guide plate by total reflection and passing through the first origin Oin is denoted as a +Yin axis, and
• when second coordinate system is assumed, in the second coordinate system, a point where a central incident light beam that includes a light beam emitted from the center point of an image forming region of the image forming apparatus and passing through the first origin Oin, is emitted from the light guide plate, is denoted as a second origin Oout, a normal line of the light guide plate passing through the second origin Oout and extending toward the side where the light is emitted from the light guide plate is denoted as a −Zout axis, and an axis parallel to the +Yin axis and passing through the second origin Oout is denoted as a +Yout axis,
• a central outgoing light beam that includes a light beam at a time of the emission of the central incident light beam from the light guide plate, intersects an Xout Yout plane at an angle different from zero degrees, or intersects an Xout Zout plane at an angle different from zero degrees, or intersects the Xout Yout plane at an angle different from zero degrees and intersects the Xout Zout plane at an angle different from zero degrees.

A display apparatus, comprising:

• a frame worn on an observer's head;
• and
• an image display apparatus attached to the frame,
• the image display apparatus includes:
• an image forming apparatus, and
• an optical apparatus into which light emitted from the image forming apparatus enters, in which the light is guided, and from which the light is emitted,
• the optical apparatus includes:
• a light guide plate in which the light propagates by total reflection and from which the incident light is emitted,
• first deflection means adapted to deflect the light entering into the light guide plate in such a manner that the light is totally reflected in the light guide plate,
• second deflection means adapted to deflect the light that has propagated in the light guide plate by total reflection in such a manner as to cause the light to be emitted from the light guide plate, and
• third deflection means adapted to deflect the light that has been deflected by the first deflection means and that has propagated in the light guide plate by total reflection toward the second deflection means, wherein
• when first coordinate system is assumed, in the first coordinate system, a point where a normal line of the light guide plate passing through a center point of the first deflection means intersects the light guide plate is denoted as a first origin Oin, a normal line of the light guide plate passing through the first origin Oin and extending toward a side where the light is emitted from the light guide plate is denoted as a −Zin axis, and an axis parallel to a traveling direction of the light that is deflected by the first deflection means and propagates in the light guide plate by total reflection and passing through the first origin Oin is denoted as a +Yin axis, and
• when second coordinate system is assumed, in the second coordinate system, a point where a central incident light beam that includes a light beam emitted from a center point of an image forming region of the image forming apparatus and passing through the first origin Oin, is emitted from the light guide plate, is denoted as a second origin Oout, a normal line of the light guide plate passing through the second origin Oout and extending toward the side where the light is emitted from the light guide plate is denoted as a −Zout axis, and an axis parallel to the +Yin axis and passing through the second origin Oout is denoted as a +Yout axis,
• a central outgoing light beam that includes a light beam at a time of the emission of the central incident light beam from the light guide plate, intersects an Xout Yout plane at an angle different from zero degrees, or intersects an Xout Zout plane at an angle different from zero degrees, or intersects the Xout Yout plane at an angle different from zero degrees and intersects the Xout Zout plane at an angle different from zero degrees.