Geophysical devices may include well logging detectors. P-pol light is light that is polarized in the plane of incidence of the light ray and a given surface, where the plane of incidence is a plane containing both the local surface normal vector and the light ray propagation direction or vector. The layer between the reflective polarizers may also be a combination of two or more films, such as a support plate and a diffuser. Such recycling cavities can be significantly thinner than standard backlights used, e. Any suitable optical elements can be used, e. In one example, referring again to FIG. A medical device comprising:
It may be desired to have light source redundancy within a zone. All of these techniques can be used to adjust base on operating conditions and based on compensation of component aging over time. Further, the zones may be any suitable plan shape, e. In some embodiments, a polarization control layer may be provided between the diffuser plate and the reflective polarizer For several reasons, the characteristic loss value is difficult to estimate by making individual loss measurements on all components. If desired, the film can be bi-axially oriented simultaneously. In addition, it may be preferred that the block axis does not leak much light at any angle of incidence and, therefore, such embodiments require either a large Brewster angle or no Brewster angle for the block axis.
The scintillator, or scintillation crystal, ceramic or polymer, may absorb ionizing waves or particles and converts the energy of the waves or particles reflrctor a light pulse. Ideally, only the emitting surfaces of the light sources are exposed in the cavity, and all other surfaces and components are covered with highly reflecting materials. In general, the pass axis of the lower absorbing polarizer can be placed in any suitable orientation relative to the viewer, e.
The front reflector is also partially transmissive. What is considered acceptable brightness and spatial uniformity depends upon the particular application for which the backlight will be used. For example, the filmscan be laminated together using optional adhesive layer Furthermore, known self-assembled periodic structures, such as cholesteric reflecting polarizers and certain block copolymers, can be considered multilayer optical films for purposes of this application.
The exemplary embodiment illustrated in FIG. In one example, the entire scintillator surface may be surrounded by specula material except for a portion of which that may be in communication with a photodetector. In general, various asymmetric reflective films can be provided for use as a front reflector e.
USB2 – Backlight and display system using same – Google Patents
In addition, the specular material may have a thickness of 0. For the embodiment flm in FIG. For purposes of explanation, light within an edge-lit backlight can be thought of as falling into two classes of angular distributions. Any suitable type of reflective polarizer may be used for the reflective polarizere. It is intended that the scope of the invention be defined by the claims appended hereto. All of the design considerations and possibilities described herein regarding the front reflectorthe back reflectorthe one or more light sourcesand the side reflectors of the backlight of FIG.
In many reflectors presently available, only two of the three characteristics may be achieved in combination at desired levels for a given application.
The brightness enhancing layer can include any suitable brightness enhancing layer or film, e. The injection optics determine the angular distribution of light at the illuminated edge s of the cavity, and thus the initial population of light within each of the two angular distributions.
S;ecular optional light management unit may also include a reflective polarizer In still another approach, such individually packaged multicolored LEDs can be positioned in one or more lines, arrays, or other patterns. Specular reflectance may be understood as the reflectance of light wherein the reflected angle is the same as the incident angle with respect to a normal plane of the sample surface.
When provided in, for example, a detector, the light pulses may be converted into electrical vikuitu via a photodetector.
The disclosure is particularly suited, but not necessarily limited, to backlights that emit visible light of substantially only one polarization state. As illustrated, backlight includes an injector that helps to direct light from the one or more light sources into the light recycling cavity Such a structured surface can be imparted a on the surface of the back reflectoror b on a transparent coating applied to the surface.
Since this second angular distribution directly supplies the emission, the rapidity of its decay primarily determines the overall uniformity of the backlight emission. The scintiallator detector may include a scintillator including a surface and may include a scintillation reflector described above, including one or more of the above recited features, surrounding at least a portion of the scintillator surface, wherein the first diffuse material is arranged proximal to the scintillator surface.
The reflective and transmissive properties of multilayer optical film are a function of the refractive indices of the respective microlayers. In some embodiments, the back reflector can be a semi-specular reflector as is further described herein. The front reflector transmits a portion of light having polarization state a while reflecting a second portion of light with state a and reflecting substantially all of light having polarization state b.
The APF front reflector increases the brightness to the normal angle cone by a factor 1. A zero or near zero magnitude z-index mismatch yields interfaces between microlayers whose reflectivity for p-polarized light is constant or near constant as a function of incidence angle.
This increases the amount of light propagating on-axis through the LC layerthus increasing the brightness of the image seen by the viewer.
This model calculates the multi-bounce loss for all ray angles and polarization states within a cavity. The control scheme could increase the brightness of the remaining light sources within a zone to further compensate for the non-functioning light source. In summary, referring to FIGS.
When provided reflecror, for example, a detector, the light pulses may be converted into electrical signals via a photodetector. As an example, the extrusion temperature may be approximately C.
CROSS REFERENCE TO RELATED APPLICATIONS
The backlight can include any backlight described herein, e. The composite reflectors may exhibit an overall thickness of 0. In other examples, the diffuse reflector may only partially cover, i.
In such instances it can be beneficial to position RGB light sources along the edge and white light sources along the back reflector. As illustrated in FIG.