Patent ID: 7928410
Filing Date: 2011-04-19
Classification: A61N

Abstract:
1. An optical beam pointing system for setting an irradiation position for radiation, the system pointing an irradiation center for radiation when positioning an irradiation target at the irradiation center, comprising: first and second optical beam pointers disposed on opposite sides of the irradiation center and opposed each other, wherein, the first optical beam pointer includes a first light-projecting portion for projecting a first visible light beam aimed at the irradiation center, the second optical beam pointer includes a second light-projecting portion for projecting a second visible light beam aimed at the irradiation center, the first optical beam pointer includes a first light-receiving portion for receiving the second visible light beam and generating a first detection signal in accordance with a receiving position at which the second visible light beam is received, the second optical beam pointer includes a second light-receiving portion for receiving the first visible light beam and generating a second detection signal in accordance with a receiving position at which the first visible light beam is received, the first optical beam pointer includes a first control portion having previously stored therein, as a first reference value, a value for the first detection signal to be generated by the first light-receiving portion which has received the second visible light beam passing through the irradiation center as aimed, the first control portion generating a first correction signal for correcting a projection angle of the second light-projecting portion when a difference between the first reference value and a value for the first detection signal actually generated by the first light-receiving portion falls outside a tolerable range, the second optical beam pointer includes a second control portion having previously stored therein, as a second reference value, a value for the second detection signal to be generated by the second light-receiving portion which has received the first visible light beam passing through the irradiation center as aimed, the second control portion generating a second correction signal for correcting a projection angle of the first light-projecting portion when a difference between the second reference value and a value for the second detection signal actually generated by the second light-receiving portion falls outside a tolerable range, the first optical beam pointer includes a first transmitting portion for transmitting the first correction signal to the second optical beam pointer, the second optical beam pointer includes a second transmitting portion for transmitting the second correction signal to the first optical beam pointer, the first optical beam pointer includes a first receiving portion for receiving the second correction signal from the second transmitting portion, the second optical beam pointer includes a second receiving portion for receiving the first correction signal from the first transmitting portion, the first optical beam pointer includes a first actuator for correcting a projection angle of the first light-projecting portion in accordance with the second correction signal received by the first receiving portion, such that the first visible light beam passes through the irradiation center, and the second optical beam pointer includes a second actuator for correcting a projection angle of the second light-projecting portion in accordance with the first correction signal received by the second receiving portion, such that the second visible light beam passes through the irradiation center.