Design of a compact multispectral telescope consisting of a Cassegrain telescope and a concave elliptical grating.

In this paper we design a high-performance multispectral telescope with a concave elliptical grating for a field of view of 3° in the VNIR spectral range of 0.48-0.82 µm, at an altitude of 760 km from the ground, with total length of 140 mm, which has a small volume and a simple structure.

Health services utilisation and responsiveness profiles in Iran: a provincial household study.

Objective: The aim of this study was to describe health services utilisation and responsiveness in East Azerbaijan province, Iran.

Design: A cross-sectional household study as part of a larger research on primary healthcare system.

Setting: We carried out the study in East Azerbaijan Province, northwest Iran from July to September 2015.

Photodoped chalcogenides as potential infrared holographic media.

The extension of holographic techniques from the visible to the infrared is important. Potentially, holographic diffractive elements have a large range of uses in this wave band. Examples include mirrors, lenses, filters, and beam combiners.