Application of 3D lithography technology in microlens fabrication
2024-07-04 17:07
The microlens array is composed of sub-lenses with diameters ranging from a few hundred nanometers to a few millimeters arranged in a certain order on a substrate, and the number of units ranges from thousands to tens of thousands. Since each sub-lens in the microlens array has a unique optical axis, if the parameters of all sub-lenses are the same, their optical properties should be the same, and when all unit structures are taken as an array as a whole, they have a main optical axis. Therefore, compared with the traditional single lens, the microlens array has extremely high parallelism. Each sub-lens can transmit optical signals independently without interfering with each other, which is equivalent to the existence of a large number of two-dimensional parallel optical paths. Each sub-lens has the function of transmitting light information, transforming imaging, etc. There are many ways to make a microlens array. We list several common production methods and focus on the application of three-dimensional lithography technology in microlens production.
1. Classification of microlens arrays Microlens arrays can be divided into planar microlens arrays and curved microlens arrays according to their different shapes.
• Planar microlens arrays are more common, and the optical axes of each sub-lens are parallel to each other, such as the microlens arrays used in light field cameras and some CCD sensors;
• The compound eye structure of insects is a typical curved microlens array, which has the advantages of large viewing angle and high resolution.
In addition to the appearance classification method, microlens arrays can also be divided into refractive microlens arrays and diffractive microlens arrays based on the principles of light refraction and diffraction.
• The sub-lens surface is smooth and continuous, mostly refractive microlens arrays, which have many advantages in imaging display, beam collimation, optical interconnection and micro scanning.