Optical transmission system and light radiating method

An optical transmission system including:

• a laser oscillator;
• a propagation optical system for propagating a laser beam emitted from said laser oscillator by a predetermined distance;
• an irradiation optical system for radiating the propagated laser beam onto an object to be irradiated;
• and
• an adjusting means for adjusting a shape of a light intensity distribution corresponding to the propagated laser beam in the direction of an optical axis or in a plane perpendicular to the optical axis and in the vicinity of the object to be irradiated;
• wherein said irradiation optical system has a focusing optical system for focusing a light beam from a light source onto the object to be irradiated at a predetermined magnification, said focusing optical system comprising two lens groups, and when the distance from a second principal plane of the first lens group to a first principal plane of the second lens group is d, the focal lengths of the first and second lens groups are f.sub.1 and f.sub.2, respectively, the distance from a predetermined position of the propagated laser beam to an object-side focal position of the first lens group is z.sub.1 and the distance from an image-side focal position of the second lens group to the object to be irradiated is z.sub.2, the following conditions are satisfied:
• d=f.sub.1 .+-.f.sub.2 .DELTA.d
• z.sub.1 =f.sub.1 f.sub.2 z.sub.2 /(z.sub.1 .DELTA.d+f.sub.1.sup.2)
• -f.sub.1.sup.2 /(f.sub.2 +.DELTA.d)<z.sub.1 <f.sub.1
• f.sub.1 >0, f.sub.2 >0
• .DELTA..sub.d >0.
• 5.

An optical transmission system including:

• a laser oscillator;
• a propagation optical system for propagating a laser beam emitted from said laser oscillator by a predetermined distance;
• and
• an irradiation optical system for radiating the propagated laser beam onto an object to be irradiated, wherein said irradiation optical system has a focusing optical system for focusing a light beam from a light source onto the object to be irradiated at a predetermined magnification, said focusing optical system comprising two lens groups, wherein a distance from a second principal plane of a first lens group to a first principal plane of a second lens group is d, the focal lengths of the first and second lens groups are f.sub.1 and f.sub.2, respectively, a distance from a predetermined position of the propagated laser beam to an object-side focal position of the first lens group is z.sub.1, and a distance from an image-side focal position of the second lens group to the object to be irradiated is z.sub.2, the following conditions are satisfied:
• d=f.sub.1 +f.sub.2 +.DELTA.d
• z.sub.1 =f.sub.1 f.sub.2 z.sub.2 /(z.sub.1 .DELTA.d+f.sub.1.sup.2)
• -f.sub.1.sup.2 /(f.sub.2 +.DELTA.dº)<z.sub.1 <f.sub.1
• f.sub.1 >0, f.sub.2 >0
• .DELTA.d>0.
• 6.