Patent ID: 7095962

Claim:
An optical transmission system comprising: a plurality of input ports to which a plurality of laser beams are respectively input; a plurality of input optical elements corresponding one-to-one to said plurality of input ports each for condensing a particular laser beam; a plurality of input reflectors corresponding one-to-one to said plurality of input optical elements each for reflecting a particular laser beam condensed; a plurality of output reflectors each for further reflecting a particular laser beam; a plurality of output optical elements corresponding one-to-one to said plurality of output reflectors each for further condensing the laser beam reflected; and a plurality of output parts corresponding one-to-one to said plurality of output optical elements each for receiving the laser beam condensed; wherein assuming that a maximum optical distance and a minimum optical distance between the input optical element closest to the input port and the output optical element closest to the output port are DL and DS, respectively, a beam radius of the laser beam at an output end of said input port, a wavelength of said laser beam, a distance between said output end and said input optical element and a focal distance of said input optical element are selected such that a beam waist position Q of said laser beam input from said input optical element closet to said input port satisfies a relation: 0.9( DL+DS )/4 ≦Q≦ 1.1( DL+DS )/4 wherein the input reflector closest to the input port has a circular configuration having a circular configuration whose radius R has a following relation or a configuration containing said circular configuration: 0.6r≦R, and there holds a relation: r = W ⁢ 1 + ( λ · x π · W 2 ) 2 where W is a beam waist radius of the laser beam, λ is a wavelength of said laser beam, x is a longer one of a distance between the beam waist position of said laser beam and said reflector closest to said input port and a distance between said beam waist position and said reflector closest to said output port, and π is a ratio of a circumference of a circle to a diameter.