Flat Microlens Array PBMLA25S-850-F50

Overview

This Flat Microlens Array is a planar diffractive element that performs two-dimensional laser beam homogenization and shaping. A square-tiled array of microlenses is patterned into a liquid crystal polymer (LCP) film bonded to a single N-BK7 window plate; the arrayed phase distribution across the film provides the microlens optical power. Each lenslet occupies a square 300 μm x 300 μm footprint within the Ø21.5 mm clear aperture, while the overall element diameter of 25.4 mm refers to the full substrate plate — not to a single lenslet. By tuning the phase period and profile of the individual microlens units, the divergence angle and output spot shape can be controlled to satisfy diverse beam-shaping requirements. This unit operates at 850 nm with a focal length of 50 mm and delivers a square output beam.

Applications

• Two-dimensional laser beam homogenization and flat-top spot generation
• Uniform square-spot illumination and beam shaping
• Structured and uniform illumination for imaging and machine vision
• Laser material processing and display / projection illumination
• Beam expansion and diffusion in compact planar assemblies

Construction & Performance

The array has a flat plate form (overall thickness 1.6 mm) with no ground curved surface: the optical power of every lenslet is produced by the graded orientation of the liquid crystal molecules, enabling micron-level fabrication precision. An anti-reflection coating on the incident surface supports high transmittance. Key specifications for this model:

• Optical element diameter: 25.4 mm
• Thickness: 1.6 mm
• Operating Wavelength: 850 nm
• Focal Length: 50 mm
• Clear Aperture: Ø21.5 mm
• Microlens unit size: 300 μm x 300 μm
• Output Beam Shape: Square
• Component Material: Liquid Crystal Polymer/N-BK7 Window Plate
• Surface Quality (Scratch/Dig): 60/40
• AR Coating: Ravg<0.5% @700-1100 nm
• Operating Temperature: -20 deg C to 60 deg C

Storage & Handling

Handle the element by its edges and avoid contact with the clear aperture. The liquid crystal polymer film is delicate, so keep the optical surfaces free of dust and fingerprints and clean only with optical-grade solvents and lens tissue when necessary, avoiding aggressive solvents that could attack the polymer. Align the square lenslet grid to the intended output-spot orientation when mounting. Store in the original container in a clean, dry environment within the rated operating temperature range, away from direct sunlight, condensation and corrosive vapors.