| 摘要 |
<p>A solar heating panel comprises a conduit (2, 3, 4, 5) for carrying a working fluid (6), such as water, for heating by solar radiation energy. The surface of the conduit facing the sun has a highly reflecting surface (13) and therefore emits little thermal radiation. The reflecting surface may be a polished conduit surface or a layer of aluminium foil fixed on the conduit. Covering the reflecting surface (13) is a coating (14) of a material absorbing to visible radiation and transparent to thermal radiation. This coating (14) may be a layer of hard carbon (18) deposited by glow discharge; or a semiconductor such as germanium or silicon in the form of particles in a plastics matrix. Alternately the coating (14) may be a layer of germanium or silicon (17) covered with a thin hard carbon layer (18); both layers (17, 18) being arranged to form an anti-reflection coating at visible wavelengths.</p> |
