Abstract: A system for detecting a target material in a sample. The system includes a sensor, a light source, an image-capturing device, two linear-crossed polarizers including a first polarizer and a second polarizer, and a processing unit. The sensor is configured to place the sample thereon and includes a fabric impregnated with liquid crystals (LCs). The light source is configured to transmit a beam of light through a path passing from the first polarizer, the sensor, and the second polarizer. The image-capturing device is configured to capture an image of a surface of the second polarizer. The image contains a pattern formed by orientations of LCs corresponding to the sample. The processing unit is configured to detect a presence of the target material in the sample by analyzing the captured image.

Abstract: A system for detecting a target material in a sample. The system includes a sensor, a light source, an image-capturing device, two linear-crossed polarizers including a first polarizer and a second polarizer, and a processing unit. The sensor is configured to place the sample thereon and includes a fabric impregnated with liquid crystals (LCs). The light source is configured to transmit a beam of light through a path passing from the first polarizer, the sensor, and the second polarizer. The image-capturing device is configured to capture an image of a surface of the second polarizer. The image contains a pattern formed by orientations of LCs corresponding to the sample. The processing unit is configured to detect a presence of the target material in the sample by analyzing the captured image.

Abstract: OLEDs having increased illumination are disclosed. The OLEDs have light emitting layers with periodic grain sizes. In particular, by depositing smaller particles at the boundaries of the emitting layers, the injection rate of carriers is improved in the emitting layers and by depositing larger particles in the middle of the emitting layers, the carrier density is increased, which increases electron-hole recombination. Increased recombination facilitates radiative emission of exitons from the OLED. As a result of the periodic grain size structure of the emitting layers, the electroluminescence and durability of the OLEDs are improved.

Abstract: OLEDs having increased illumination are disclosed. The OLEDs have light emitting layers with periodic grain sizes. In particular, by depositing smaller particles at the boundaries of the emitting layers, the injection rate of carriers is improved in the emitting layers and by depositing larger particles in the middle of the emitting layers, the carrier density is increased, which increases electron-hole recombination. Increased recombination facilitates radiative emission of exitons from the OLED. As a result of the periodic grain size structure of the emitting layers, the electroluminescence and durability of the OLEDs are improved.