Beam irradiation apparatus

Abstract

An attachment lens is arranged in a stage subsequent to a scanning lens. After a laser beam is converged by the scanning lens, the laser beam is converted into a parallel beam by the attachment lens. When the scanning lens is displaced in a direction perpendicular to an optical axis of the laser beam, a traveling direction of the laser beam is bent by a predetermined angle immediately after the laser beam passes through the scanning lens. Then, the traveling direction of the laser beam is further bent by a predetermined angle in the same direction by the passage of the laser beam through the attachment lens. Accordingly, a final swing angle of the laser beam outgoing from an outgoing window is increased by a swing angle imparted by the attachment lens compared with the case where the attachment lens is not arranged. One of lens surfaces of the attachment lens is formed in a toroidal surface, which allows the laser beam to have a long outline in a vertical direction.

1 . (canceled) 
   
   
       2 . (canceled) 
   
   
       3 . A beam irradiation apparatus comprising:
 a light source which emits a laser beam;   a first lens which displaces a traveling direction of the laser beam emitted from the light source toward a direction perpendicular to an optical axis of the laser beam;   an actuator which drives the first lens; and   a second lens which imparts wide angle action to a swing angle of the optical axis, the swing angle being generated by displacing the first lens, wherein   the second lens includes a first lens surface which imparts the wide angle action to the laser beam and a second lens surface which adjusts an outline of the laser beam.   
   
   
       4 . A beam irradiation apparatus comprising:
 a light source which emits a laser beam;   a first lens which displaces a traveling direction of the laser beam emitted from the light source toward a direction perpendicular to an optical axis of the laser beam;   an actuator which drives the first lens; and   a second lens which imparts wide angle action to a swing angle of the optical axis, the swing angle being generated by displacing the first lens, wherein   the first lens converges the laser beam smaller than a parallel beam,   the second lens diffuses the laser beam converged by the first lens into a substantially parallel state, and   the second lens includes a first lens surface which imparts the wide angle action to the laser beam and a second lens surface which adjusts an outline of the laser beam.   
   
   
       5 . (canceled) 
   
   
       6 . The beam irradiation apparatus according to  claim 3 , wherein
 the second lens surface imparts optical action to the laser beam such that the outline of the laser beam becomes thin in one direction.   
   
   
       7 . The beam irradiation apparatus according to  claim 4 , wherein
 the second lens surface imparts optical action to the laser beam such that the outline of the laser beam becomes thin in one direction.   
   
   
       8 . (canceled) 
   
   
       9 . A beam irradiation apparatus comprising:
 a light source which emits a laser beam;   a scanning unit which scans the laser beam emitted from the light source within a target region; and   an optical member which deforms an outline of the laser beam in the target region so as to become thin in one direction.   
   
   
       10 . The beam irradiation apparatus according to  claim 9 , wherein
 the scanning unit scans the laser beam in at least a horizontal direction within the target region, and   the optical member deforms the outline of the laser beam in the target region so as to become thin in a direction perpendicular to the horizontal direction.   
   
   
       11 . The beam irradiation apparatus according to  claim 9 , wherein
 the scanning unit includes a first lens and an actuator, the laser beam being incident from the light source to the first lens, and the actuator driving the first lens in a direction perpendicular to an optical axis of the laser beam, and   the optical member includes a second lens which imparts focus action to the laser beam, a focal distance in the horizontal direction being different from a focal distance in the vertical direction in the focus action.   
   
   
       12 . The beam irradiation apparatus according to  claim 9 , wherein
 the scanning unit includes a first lens and a polygon mirror, the laser beam being incident from the light source to the first lens, and the polygon mirror having a plurality of reflection planes which reflect the laser beam incident from the first lens, and   the optical member includes a second lens which imparts focus action to the laser beam, a focal distance in the horizontal direction being different from a focal distance in the vertical direction in the focus action.   
   
   
       13 . The beam irradiation apparatus according to  claim 11  or  12 , wherein
 the second lens includes a first and a second passing surfaces through which the laser beam passes, and the first passing surface is formed in a lens surface which imparts the focus action to the laser beam, the focal distance in the horizontal direction being different from the focal distance in the vertical direction in the focus action.   
   
   
       14 . The beam irradiation apparatus according to  claim 13 , wherein
 the lens surface is a toroidal surface in which the focal distance in the horizontal direction is different from the focal distance in the vertical direction.