Due to the high dependence of our thermal emission behaviour on the wavelength of the heat source due to the extreme dependence of our thermal emission behavior on the wavelength, only certain wavelengths are suitable for thermal measurements. The following figures show the range of thermal transmission for common windows and thermal lenses for infrared thermometers. The blue-colored curve represents the general rule that applies to all materials. It is the average of a temperature range of zero (black) and infinity (green), and that is the cold pressure limit (CPL).
For windows and lenses, the cold-pressure limit is defined as the maximum measured value of the damping ratio of a material in relation to the thermal gradient. This ratio is plotted as a function of the temperature differential across the viewing angle for a given viewing angle and the cte of the lens or window. The bending moment of a system is the variation in the angle of incidence, which is linear or spherical. This results in the slope being proportional to this curve. The slope of this curve is also proportional to the focal length of a system, which can be considered as a function of the focal length divided by the period of the curve (i.e. the period between shots).
For a set of temperatures and a given focal length of a window or lens assembly, the internal surface temperature of the system will always be within the prescribed curve in the perfect order called a “curved surface.” The thermal conductance curve of a glass bead inside a glass vial could be plotted as a function of the focal length, the temperature difference between the bottom and the vial’s surface and the angle of incidence of a particular window. If the aperture is fixed for all shots, then the area between the system’s surface temperature and the curve of variation should remain constant. Variable apertures can cause the curve to become curvilinear due to variations in the temperature of the glass used to make the bead, ambient air temperature, focal length, and time of photography. A signature left by an artist on the petals of a flower is an example of a curving surface.
A window and lens should be mounted in a way that their focal points and lines of sight are properly aligned. If the interior surface temperature of the system is too cold for the lens, the outside temperature of the frame and the interior temperature will be too high. The frame will not need to be adjusted to account for internal temperature fluctuations or cooling effects. If there are no temperature variations from outside, the frame’s internal temperature will be the same for a given focal length. If the system is located in an area with limited or obstructed views of the surrounding structures or landscape, it may be necessary to control internal temperatures.
The first mechanical interlocking system used to mount lenses to camera were made of plastic. This design was later used to create pinhole glasses. This kind of lens assembly comes with a drawback: the mechanical joints between the frame and the lens could crack or indent. If this should be occurring, it would be required for the entire assembly to be replaced in a short time. Because of this the type of system has been replaced by more robust designs.
Pinhole glasses lenses are typically constructed with a frame made of metal and a thin, plastic or glass lid. At the very least the lense designs should include a hermetically sealed lens construction. A hermetically sealed lens construction has a sealed surface on the top and bottom of the lens assembly. The top surface could contain an elastomeric seal that is similar to that previously mentioned. Additionally, it could contain some other substance, for instance, an adhesive, a lip or a layer of plastic film.
Another embodiment of this type of window and lens assembly includes an lens surface that is a substratethat is attached to the base of the window assembly. This type of system is typically comprised of a window casing and a series of compartments for lenses. Other types of devices could be integrated into the windows, such as thermometers and light emitters. In certain instances, the device used to regulate the temperature within the room could also be part of this kind of system. A number of compartments could be used to house the temperature control and a variety of other devices such as an alarm clock, thermostat, or other devices.
This isn’t an exhaustive list of all types of window and lens assemblies. It’s an indication of the most important technologies that are related to this invention. Please refer to the entire disclosure for more details. Particularly, you should look over the sections that pertain to “details of the present invention” and “Description of the Method with Regard to the Identification of the Various Classes of Products That Are involved in the Present Application.”
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