| 摘要 |
<p>Known antireflection coating for optical glass consists of three layers viz a layer adjacent to glass has a thickness of lambda/4 and an index of refraction nD = 1.58-1.70, an intermediate lambda/2 layer has nD = 1.85-2.40, and a lambda/4 top layer has nD = 1.30-1.45. This coating is improved in that the intermediate lambda/2 layer consists of four lambda/8 sublayers divided by very thin (1-10 m mu, pref. 5 mu) intermediate layers having a lower index of refraction. The top layer and the intermediate layer are pref. made of MgF2. The bottom layer is pref. CeF3 or Al2O3. The sublayers are made of CeO2 or ZrO2. ZrO2, which is pref. used for the intermediate lambda/2 layer because of the stable high index of refraction and high absorptivity. This layer is split into four lambd/8 sublayers sepd. by intermediate layers having a lower index of refraction to prevent density decrease.</p> |
