OPTICAL SPACE TRANSMITTER

PROBLEM TO BE SOLVED: To provide an optical space transmitter where the reliability of optical beam transmission reception can considerably be enhanced. SOLUTION: A shield member made of a transparent or translucent material that shields the outside of a case 2 from the inside of the case 2 to the surface of which hydrophilic treatment is applied is provided to an optical beam incident/emission section 3 in the case 2 containing an optical beam transmission reception means that emits or receives an optical beam modulated by an information signal in the optical space transmitter 10. Or the shield member made of a transparent or translucent material that shields the outside of the case 2 to the surface of which hydrophobic treatment is applied from the inside of the case 2 is provided to the optical beam incident/emission section 3 in the case 2 containing an optical beam transmission reception means that emits or receives an optical beam modulated by an information signal in the optical space transmitter 10.