Single Pane Of Glass Research Articles

A Writer's Need to See

As a writer who has come to photography recently, I am particularly interested in how taking pictures relates to writing. Several years ago, at work on a memoir, I lost the ability to see my immediate surroundings with acuity. Then, on a trip to Mexico in 1998, my eyes were reawakened. I began working with disposable cameras because they were readily available in the shops around the town square. I did not expect to go on using them, but I have discovered special qualities, which I continue to explore. With a disposable camera one cannot select the depth of field. Rather than foregrounding a central object when I gaze into a store window, I become interested instead in all that a single pane of glass can contain.

Thousand kW solar furnace, built by the National Center of Scientific Research, in Odeillo (France)

The thousand kW solar furnace was completed in 1970. The furnace contains 63 orientator mirrors, each of 45 m 2 surface, with 180 single mirror panes. The movement of this installation is guided by electronic controls operated by reflected rays. The accuracy of the control is 1 min of arc, but due to dispersion on the flat glass 5 min of arc are obtained on the reflected rays. A solar beam of constant energy is directly horizontally southward to a paraboloid reflector of 2000 m 2 intercepted area. This paraboloid contains 9500 single glass panes, bent by mechanical constraint and adjusted to reflect maximum radiation to the focal plane, situated 18 m from the apex of the parabola. Results of tests concerning the energy received at the focal image are as follows: (1) The energy collection closely agrees with calculations, taking into account the factors of reflection of glass, and the dispersion due to imperfect curvatum of mirrors and to shading. (2) Power beyond 1000 kW was obtained with the device, when the incident solar energy was more than 0·1 W/cm 2. (3) The energy concentration in the center of the focus-image is equal to black-body radiation around 3800°C.