Coronograph, Reflective, Basic
Sunday, September 03, 2006
The basic design of the Coronagraph incorporates an occulting disk in the primary image plane of the telescope. This occulting disk blocks the image of the Sun. The primary objective (a lens or polished mirror) is specified to minimizing scattered light. The light diffracted by the objective edge is minimized. An aperture (Lyot Stop, invented by B. Lyot) is located at the image of the objective formed by a field lens, with an aperture slightly smaller than the objective image. A relay lens behind the Lyot stop forms the Sun corona image at the final image plane.
The Reflective Coronagraph primary mirror (and secondary mirror) is made of high quality material and is coated and polished to high specifications. The Coronagraph has an annular field mirror located at the image plane formed by the primary objective. The image of the Sun’s disk passes through the hole in the annular mirror. The field mirror reflects the image to the field lens system that forms the final image. A Lyot stop is located at the image formed by the field mirror, which is the image of the entrance aperture.
Source: Various Publications
Reference: Raymond N. Smartt.
Industrial Products
posted by JD52 @ 12:32 AM,
