Rotary laser apparatus

A rotary laser apparatus comprising a light-projecting section and a rotation-irradiating section,

• said light-projecting section comprising a laser beam projector for emitting a projecting laser beam, a collimator lens for converting the laser beam emitted from the laser beam projector to a parallel beam, and a fixed cylinder rotatably supporting a rotary cylinder to be rotated around an optical axis of the collimator lens,
• said rotation-irradiating section comprising first, second and third optical members and said rotary cylinder, said first, second and third optical members being configured to form first, second and third fan-shaped laser beams, respectively, each having a fan-shaped plane expanding as the laser beam goes apart from said axis,
• said first optical member comprising a first penta prism and a first lens, said first penta prism comprising an incident plane which is orthogonal to the optical axis of the collimator lens and into which parallel light beam is led, a permeable plane which reflects a part of the parallel light beam entering the incident plane and permeates the remainder therethrough, an emitting plane, and a reflecting plane which biases the parallel light beam reflected from the permeable plane in a direction orthogonal to the optical axis of the collimator lens and reflects the beam toward the emitting plane, said first lens converting the parallel light beam emitted from the emitting plane to a first fan-shaped laser flux,
• said second optical member comprising a second penta prism and a second lens, said second penta prism comprising an incident plane which is orthogonal to the optical axis of the collimator lens and into which the parallel light beam having permeated the permeable plane of the first penta prism are led, a permeable plane which reflects a part of the parallel light beams entering the incident plane and permeates the remainder therethrough, an emitting plane, and a reflecting plane which biases the parallel light beam reflected from the permeable plane in a direction orthogonal to the optical axis of the collimator lens and reflects the beam toward the emitting plane, the second lens converting the parallel light beam emitted from the emitting plane to a second fan-shaped laser flux,
• the third optical member comprising a third penta prism and a third lens, said third penta prism comprising an incident plane which is orthogonal to the optical axis of the collimator lens and into which a parallel light beam having permeated the permeable plane of the second penta prism is led, a first reflecting plane which reflects the parallel light beams entering the incident plane, an emitting plane, and a second reflecting plane which biases the parallel light beam reflected from the permeable plane in a direction orthogonal to the optical axis of the collimator lens and reflects the be am toward the emitting plane, the third lens being configured for converting the parallel light beam emitted from the emitting plane to a third fan-shaped laser flux,
• a first beam splitter being provided between the permeable plane of the first penta prism and the incident plane of the second penta prism, the beam splitter burying a gap between the first penta prism and the second penta prism, and determining a transmittance/reflectance,
• a second beam splitter being provided between the permeable plane of the second penta prism and the incident plane of the third penta prism, the beam splitter burying a gap between the second penta prism and the third penta prism, and determining a transmittance/reflectance,
• an auxiliary member for supplementing pressing being provided at the first reflecting plane of the third penta prism, said auxiliary member having a pressing surface parallel to the first reflecting plane and the incident planes,
• the first penta prism and the third penta prism being axially fixed in the rotary cylinder under pressure, holding the second penta prism therebetween, while the emitting planes of the first and third penta prisms and being deviated from each other in a rotating direction of the rotary cylinder 9, such that the first and third fan-shaped planes of the first and third fan-shaped laser beams, respectively may form the specific angle and that the first and third fan-shaped planes of the first and third fan-shaped laser beams, respectively may be symmetrical with each other via the fan-shaped plane of the second fan-shaped laser beam 9b.