Fujifilm Corporation

Takeshi Iida

Hiroki Takahashi

Provided is an antireflection film having excellent abrasion resistance. In the antireflection film, a hydrogenated carbon film as a first layer is formed on a surface of an optical substrate. A MgFfilm as a second layer having a lower refractive index than the first layer is formed on the first layer. Likewise, a third layer formed of the hydrogenated carbon film, a fourth layer formed of the MgFfilm, and a fifth layer formed of the hydrogenated carbon film are formed. During the formation of the hydrogenated carbon film, a mixed gas of argon and hydrogen is supplied to a vacuum chamber such that some of C&#x2014;C bonds in the film are replaced with C&#x2014;H bonds. Due to the C&#x2014;H bonds, an antireflection film having excellent abrasion resistance and adhesiveness and having a low refractive index can be obtained.

Antireflection film, lens, and imaging device

In the antireflection film, a hydrogenated carbon film as a first layer is formed on a surface of an optical substrate. A MgFfilm as a second layer having a lower refractive index than the first layer is formed on the first layer and functions as a low refractive index layer. The hydrogenated carbon film and the MgFfilm are formed using a RF magnetron sputtering equipment. During the formation of the hydrogenated carbon film, a mixed gas of argon and hydrogen is supplied to a vacuum chamber such that some of C&#x2014;C bonds in the film are replaced with C&#x2014;H bonds. Some of C&#x2014;C bonds are cut by hydrogenation, and strains (stress) accumulating due to C&#x2014;C bonds can be relaxed. As a result, the antireflection film which has excellent adhesiveness and is not broken is obtained.

Growing community of inventors

Sano, Japan

Takeshi Iida