A wavefront at high radio frequencies or optical frequencies impinging on the atmosphere is distorted.

高射电频率或光学频率的波阵面进入大气时受到畸变。

youdao

The best-known is probably the Hubble Space Telescope , which operates at optical frequencies.

ECONOMIST: Telescopes are getting bigger, better and less tangible

Some experts in the field seriously question whether it is possible to develop materials capable of perfect lensing at optical frequencies.

BBC: Last Updated: Monday, 8 March 2004, 09:03 GMT

The extent of the problem, at least at optical frequencies, has recently been catalogued by Pierantonio Cinzano and Fabio Falchi at the University of Padua, Italy, and Christopher Elvidge at the National Geophysical Data Centre in Boulder, Colorado.

ECONOMIST: Going, going, nearly gone