Total internal reflection prism unit, total internal reflection prism assembly including the same and apparatus for forming a line beam including the same

A total internal reflection prism assembly, comprising:

• a total reflection incidence prism unit including a first incidence prism and a second incidence prism, the first and second incidence prisms being arranged on top of each other along a vertical direction,
• the first incidence prism including
• a first total reflection incidence surface and a second total reflection incidence surface, the first total reflection incidence surface to totally reflect a light, which is incident in a first horizontal direction, along a second horizontal direction substantially perpendicular to the first horizontal direction, the second total reflection incidence surface to totally reflect the totally reflected light from the first total reflection incidence surface along the first horizontal direction to form a first incidence beam, and the second incidence prism including
• a third total reflection incidence surface and a fourth total reflection incidence surface, the third total reflection incidence surface to totally reflect the light, which is incident in the first horizontal direction, along a third horizontal direction substantially perpendicular to the first horizontal direction, and the fourth total reflection incidence surface to totally reflect the totally reflected light from the third total reflection incidence surface along the first horizontal direction to form a second incidence beam discrete from the first incidence beam along the third horizontal direction;
• and
• a total reflection exit prism unit including a first exit prism and a second exit prism, the first exit prism including
• a first total reflection exit surface and a second total reflection exit surface, the first total reflection exit surface to totally reflect the first incidence beam along a first vertical direction, the second total reflection exit surface to totally reflect the totally reflected beam from the first total reflection exit surface along the first horizontal direction to form a first exit beam, and
• the second exit prism including a third total reflection exit surface and a fourth total reflection exit surface, the third total reflection exit surface to totally reflect the second incidence beam along a second vertical direction, and the fourth total reflection exit surface to totally reflect the totally reflected beam from the third total reflection exit surface along the first horizontal direction to form a second exit beam discrete from the first exit beam along the third horizontal direction.

An apparatus for forming a line beam, the apparatus comprising:

• a total reflection incidence prism unit including a first incidence prism and a second incidence prism, the first and second incidence prisms being arranged on top of each other along a vertical direction,
• the first incidence prism including a first total reflection incidence surface and a second total reflection incidence surface, the first total reflection incidence surface to totally reflect a light, which is incident in a first horizontal direction, along a second horizontal direction substantially perpendicular to the first horizontal direction, the second total reflection incidence surface to totally reflect the totally reflected light from the first total reflection incidence surface along the first horizontal direction to form a first incidence beam, and
• the second incidence prism including a third total reflection incidence surface and a fourth total reflection incidence surface, the third total reflection incidence surface to totally reflect the light, which is incident in the first horizontal direction, along a third horizontal direction substantially perpendicular to the first horizontal direction, and the fourth total reflection incidence surface to totally reflect the totally reflected light from the third total reflection incidence surface along the first horizontal direction to form a second incidence beam discrete from the first incidence beam along the third horizontal direction;
• a total reflection exit prism unit including a first exit prism and a second exit prism,
• the first exit prism including a first total reflection exit surface and a second total reflection exit surface, the first total reflection exit surface to totally reflect the first incidence beam along a first vertical direction, the second total reflection exit surface to totally reflect the totally reflected beam from the first total reflection exit surface along the first horizontal direction to form a first exit beam, and
• the second exit prism including a third total reflection exit surface and a fourth total reflection exit surface, the third total reflection exit surface to totally reflect the second incidence beam along a second vertical direction, and the fourth total reflection exit surface to totally reflect the totally reflected beam from the third total reflection exit surface along the first horizontal direction to form a second exit beam discrete from the first exit beam along the third horizontal direction;
• and
• a condensing lens unit to condense the first and second exit beams exiting from the total reflection exit prism unit along the second and third horizontal directions to form the line beam.