A new class of telescope is being built with primary mirrors as large as 8.4 meters in diameter and as fast as f/i . Fabricating the secondary mirrors for these telescopes has presented tough challenges because of their large sizes, up to 1.7 meter diameter; their aspheric departure of more than 300 microns; the required figure accuracy of a few tens of nanometers; and the fact that they are ty...

A significant issue in the design of catadioptric imaging systems is what shape the component mirrors should take. In this paper, we propose a novel algorithm for designing a free-form mirror. A free-form mirror expressed as the assembly of its gradients, is the most flexible surface representation that can form various shapes. We improve the shape reconstruction framework used in a photometric...

We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror,...

We present recent results on the inspection of a first diffraction-limited hard X-ray Kirkpatrick-Baez (KB) mirror pair for the Coherent X-ray Imaging (CXI) instrument at the Linac Coherent Light Source (LCLS). The full KB system - mirrors and holders - was under inspection by use of high resolution slope measuring deflectometry. The tests confirmed that KB mirrors of 350mm aperture length char...

Legislation and product development in the USA has prompted an interest in mirror-use by traffic flaggers to improve awareness of vehicles approaching from behind. Helmet- and flagpole-mounted configurations were studied using a graphical approach with field verification studies by comparing fields of view, object magnifications, and human factors considerations. Plane and convex mirrors with d...

We make some remarks on Berry's paper [Eur. Berry just presented a comprehensive explanation of the physical part for the optics of the magic mirror [1]. The story related to this strange metal mirror could be traced in [2-4]. The characteristic is : the raised images appeared in a screen are on the opposite side of an opaque mirror but not the reflecting face [5-6]! This amazing optical effect...

Linewidth measurements of a distributed feedback (DFB) fibre laser are made using delayed self heterodyne interferometry (DHSI) with both Mach-Zehnder and Michelson interferometer configurations. Voigt fitting is used to extract and compare the Lorentzian and Gaussian linewidths and associated sources of noise. The respective measurements are w(L) (MZI) = (1.6 ± 0.2) kHz and w(L) (MI) = (1.4 ± ...

A novel concept for octave spanning dispersive mirrors with low spectral dispersion oscillations is presented. The key element of the so-called wedge dispersive mirror is a slightly wedged layer which is coated on a specially optimized dispersive multilayer stack by a common sputter coating process. The group delay dispersion (GDD) of a pulse reflected on a wedge dispersive mirror is nearly fre...

The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is designed to explore the gamma-ray sky between 20 and 250 GeV using the atmospheric Cherenkov technique. STACEE will use large solar heliostat mirrors to reflect Cherenkov light created in gamma-ray air showers to secondary mirrors on a central tower. The secondary mirrors image this light onto photomultiplier tube cameras that ...

In this work were built mirrors with multilayer film of aluminum-silicon dioxide, deposited in glass substratum in a RF-Sputtering chamber, with a view to optimize the reflection inside the cavity of a nitrogen laser that operates in the UV region (337,1 nm). It’s introduced a theoretical simulation of the variation of reflectivity in function of the number of layers, carrying in consideration ...