Radiation emitted by a radiation source (208, 408) along a projected path P0 can be diverted by a divergence angle by a lens (234, 434) in the projected path P0 with a first surface (236, 436) and a second surface (240, 440) spaced apart along the projected path P0 with the second surface (240, 440) farther from the radiation source (208, 408) than the first surface (236, 436). The first surface (236, 436) can be curved and have a normal point perpendicular to a line parallel to the projected path P0 and offset from the projected path P0 by an eccentricity. Radiation striking the first surface (236, 436) can be diverted by a first angle relative to the projected path P0 and can continue to strike the second surface (240, 440), which diverts the radiation by a second angle. The sum of the first and second angles is the divergence angle. The apparatus can be used in a probe assembly (200) to determine tip clearance of a turbine blade (120) during operation of a gas turbine engine (50).
- 출원번호 : 24201048.6
- 출원인 : General Electric Technology GmbH
- 특허번호 :
- IPC : G01B-011/14(2006.01);F01D-011/20(2006.01);F01D-021/00(2006.01);