Abstract: A dual-pane thermal window unit comprises two non-intersecting or, preferably, substantially parallel, spaced window panes, mounted in a window frame, a first of the panes having affixed thereto a first wall of an electro-optical liquid crystal cell providing a selected light transmittance, and a second of said panes delimiting, with a second wall of said cell, a space providing a thermal break. Each of the first and second walls comprises an electrically conductive film composed of plastic and having sufficient supporting strength to maintain the structural integrity of the cell. The window is light weight, economical to manufacture and efficient and reliable in operation.

Abstract: A dual-pane thermal window unit comprises two non-intersecting or, preferably, substantially parallel, spaced window panes, mounted in a window frame, a first of the panes having affixed thereto a first wall of an electro-optical liquid crystal cell providing a selected light transmittance, and a second of said panes delimiting, with a second wall of said cell, a space providing a thermal break. Each of the first and second walls comprises an electrically conductive film composed of plastic and having sufficient supporting strength to maintain the structural integrity of the cell. The window is light weight, economical to manufacture and efficient and reliable in operation.

Abstract: A dual-pane thermal window unit comprises two non-intersecting or, preferably, substantially parallel, spaced window panes, mounted in a window frame, a first of the panes having affixed thereto a first wall of an electro-optical liquid crystal cell providing a selected light transmittance, and a second of said panes delimiting, with a second wall of said cell, a space providing a thermal break. Each of the first and second walls comprises an electrically conductive film composed of plastic and having sufficient supporting strength to maintain the structural integrity of the cell. The window is light weight, economical to manufacture and efficient and reliable in operation.

Abstract: A dual-pane thermal window unit comprises two nonintersecting or, preferably, substantially parallel, spaced window panes, mounted in a window frame, a first of the panes having affixed thereto a first wall of an electro-optical liquid crystal cell providing a selected light transmittance, and a second of said panes delimiting, with a second wall of said cell, a space providing a thermal break. Each of the first and second walls comprises an electrically conductive film composed of plastic and having sufficient supporting strength to maintain the structural integrity of the cell. The window is light weight, economical to manufacture and efficient and reliable in operation.

Abstract: A method and apparatus are provided for monitoring in situ the transformation of some fraction of a starting material to another material during the course of a thermal treatment. The starting material is heated to a preselected temperature and its permeability is measured. A signal is transmitted to an actuator, which indicates cooling of the material when a preselected or change therein is detected.

Abstract: A method and apparatus for spectroscopic gas analysis are provided. Plural beams of monochromatic radiation are directed through gaseous material. A tuning mechanism adjusts the frequency difference between the radiation beams to equal substantially an odd integral submultiple of the frequency difference between adjacent spectral components of the periodic spectrum for a preselected constituent of the gaseous material. Radiation scattered by the gaseous material is received by a filtering mechanism adapted to transmit selectively a detectable signal composed of a single superimposed spectral component of the spectrum. The signal is received by a detecting means which indicates the intensity thereof.