Apparatus for adjusting light beam direction

An apparatus for adjusting light beam direction comprising a first prism, a second prism, a third prism and a fourth prism arranged along an incident direction of the light beam, characterized in that

• an incident face of the first prism is defined by rotating a vertical plane which is perpendicular to the incident direction, around a first rotational axis parallel to the vertical plane by a first acute angle;
• an outgoing face of the first prism is defined by rotating the vertical plane in the same direction as that of the first acute angle around the first rotational axis by a second acute angle larger than the first acute angle;
• an incident face of the second prism is parallel to the outgoing face of the first prism at zero-adjusting state;
• an outgoing face of the second prism is parallel to the incident face of the first prism at the zero-adjusting state;
• at least one of the first and second prisms is designed to adjustably rotate around a rotational axis parallel to the first rotational axis;
• an incident face of the third prism is defined by rotating the vertical plane around a second rotational axis perpendicular to both the incident direction and the first rotational axis by a third acute angle;
• an outgoing face of the third prism is defined by rotating the vertical plane in the same direction as that of the third acute angle around the second rotational axis by a fourth acute angle larger than the third acute angle;
• an incident face of the fourth prism is parallel to the outgoing face of the third prism at the zero-adjusting state;
• an outgoing face of the fourth prism is parallel to the incident face of the third prism at the zero-adjusting state;
• and
• at least one of the third and fourth prisms is designed to adjustably rotate around the second rotational axis.

An apparatus for adjusting light beam direction comprising a first prism and second prism which have an incident face and an outgoing face non-parallel with one another and are arranged along an incident direction of the light beam, characterized in that

• the first prism is designed to adjustably rotate around a first rotational axis perpendicular to the incident direction;
• the second prism is designed to adjustably rotate around a second rotational axis perpendicular to both the incident direction and the first rotational axis;
• an incident face of the second prism is made parallel to an outgoing face of the first prism at zero-adjusting state;
• an outgoing face of the second prism is made parallel to an incident face of the first prism at the zero-adjusting state;
• and
• an intersectional line of an extended incident face and an extended outgoing face of each prism is non-parallel to both the first and second rotational axes.

A light scanning apparatus comprising a light source;

• a deflecting system for deflecting the light beam emitted from the light source;
• a scanning lens for imaging the light beam deflected by the deflecting system on a subject to be scanned;
• and an apparatus for adjusting light beam direction comprising a first prism and a second prism which have an incident face and an outgoing face non-parallel with one another and are arranged along an incident direction of the light beam. wherein
• the first prism is designed to adjustably rotate around a first rotational axis perpendicular to the incident direction:
• the second prism is designed to adjustably rotate around a second rotational axis perpendicular to both the incident direction and the first rotational axis;
• an incident face of the second prism is made parallel to an outgoing face of the first prism at zero-adjusting states;
• an outgoing face of the second prism is made parallel to an incident face of the first prism of the zero-adjusting state;
• and
• a virtual intersectional line of an extended incident face and an extended outgoing face of each prism is non-parallel to both the first and second rotational axes;
• wherein the apparatus for adjusting light beam direction is disposed between the light source and the deflecting system, in the light path.

An apparatus for adjusting light beam direction, said light beam originating at a light beam source and having a light beam axis, said apparatus comprising:

• a first prism disposed at a first point on said light beam, said first prism having an incident face and an outgoing face,
• a second prism disposed at a second point on a light beam, said second point being behind said first point relative to said light beam source, said second prism having an incident face and an outgoing face, said incident face of said second prism being parallel to said outgoing face of said first prism at a zero-adjusting state, said outgoing face of said second prism being parallel to said incident face of said first prism at said zero-adjusting state;
• and
• means for rotating at lest one of said first and second prisms about an axis parallel to said light beam axis.

An apparatus for adjusting light beam direction comprising a first prism, a second prism, a third prism and a fourth prism arranged along an incident direction of the light beam, characterized in that:

• said first prism has an incident face and an outgoing face.
• said second prism has an incident face and an outgoing face, said incident face of said second prism being parallel to said outgoing face of said first prism at a zero-adjusting state, said outgoing face of said second prism being parallel to said incident face of said first prism at said zero-adjusting state;
• at least one of said first and second prisms is designed to adjustably rotate around a rotational axis;
• said third prism has an incident face and an outgoing face;
• said forth prism has an incident face and an outgoing face, said incident face of said forth prism being parallel to said outgoing face of said third prism at the zero-adjusting state, said outgoing face of said fourth prism being parallel to said incident face of said third prism at said zero-adjusting state;
• at least one of said third and fourth prisms is designed to adjustably rotate around a rotational axis;
• and
• means for compensating for chromatic aberration, said means existing inherently within the interaction of said first, second, third and fourth prisms.