Diffractive phase-shift lithography photomask operating in proximity printing mode.

A phase shift proximity printing lithographic mask is designed, manufactured and tested. Its design is based on a Fresnel computer-generated hologram, employing the scalar diffraction theory. The obtained amplitude and phase distributions were mapped into discrete levels.

Holographic technique for measurement of the kinetic constant and optical modulation of photosensitive materials.

We use a holographic technique to measure simultaneously and separately the temporal evolution of the refractive-index and the absorption coefficient modulations induced by light in a photosensitive material. The technique is phase sensitive, allowing separation of the signals from the phase and from the amplitude grating. The refractive-index and the absorption coefficient modulations as well as the kinetic constant of the photoreaction in the positive photoresist SC 1827 were measured at three different wavelengths.

Metallized photoresist grating as a polarizing beam splitter.

We propose and demonstrate the use of a simple holographic relief photoresist grating covered with an aluminum film as a reflecting polarizing beam splitter. The polarizing effects were achieved as a result of the nonsinusoidal profile of the grating. The best parameters of the gratings for optimizing the polarizing-beam-splitting properties were found by the introduction of the experimental profiles in diffraction calculation software.

Diffractive structures holographically recorded in amorphous hydrogenated carbon (a-C:H) films.

We propose and demonstrate the direct recording of submicrometer relief gratings in amorphous hydrogenated carbon (a -C:H) films by reactive ion etching (RIE) for use as diffractive optical components. The high refractive index of this film and its transparency in the IR make such structures promising candidates for IR-transmission diffractive optical components. The structures are holographically recorded in photoresist and then transferred to a thin aluminum layer that is used as a mask for RIE of the a -C:H films.

Bulk photochromism in a tungstate-phosphate glass: a new optical memory material?

In this work, we present a new photochromic tungstate based glass which have both absorption coefficient and refractive index modified under laser exposure. The photosensitive effect is superficial under ultraviolet (UV) irradiation but occurs in the entire volume of the glass under visible irradiation. The effect can be obtained in any specific point inside the volume using an infrared femtosecond laser.