Microlens arrays are a combination of two or more small lenses that tend to form a periodic pattern of a square or hexagon on the substrate. Practically, the microlens is identified by the user in three forms- a thin transparent layer, homogenous glass, and semiconductor substrate. Each microlens is characterized by its parameters such as diameter, focal length, and wavelength.
Due to a number of potential features, Micro lens arrays are being used in optical and non-optical devices such as:
- 4–D Imaging: Due to its robust features, the microlens is regarded as a convenient method for visualizing 4-D information on the target. It has the potential to stimulate exotic microscope illumination modalities and correct optical aberrations digitally.
- Coupling and Optical Components: Microlens acts as a coupling element in a number of fiber optics communication tools. These lenses are used to solve the refractive and diffractive power coupling efficiency that results in a single material. With its help, the rate of coupling loss is reduced even if the wavelength of the Gaussian beam is increasing. Microlens works best with optical components such as detector, power meter, and data analyzer.
- Photovoltaics: Some advanced types of Microlenses act as a concentrator for high-efficiency photovoltaics for electricity production. The micro-optical structure of the lens absorbs and scatters the inclined light on the intended solar cell. It also promotes better conversion efficiency by filling the weak factors in the path. In addition to this, the microlens has the capacity to improve the electricity generation by 4 times than the normal lens. In fact, a hybrid of microlens structure and the curved surface can generate a high value-added micro-optic performance. All this makes microlens array an ideal substrate for thin-film solar cells.
- Photography: Due to the availability of arrays, spherical microlenses are considered as integral components in cameras. Generally, microlens arrays are used in a plenoptic camera with the objective to achieve light field photography. Unlike other lenses, these also eliminate the need for initial focusing before capturing the image. To move a step further, colloidal micro-lenses enable the detection of single molecule, when it is used in conjunction with a low-light lens.
Micro lenses are playing a significant role in stimulating the overall performance of several devices. In regard to future advancements, they will be used in almost every major industry including medical science, laser material processing, lidar/ladar application, communication, and sensors.