A Novel Approach for a Chip-Sized Scanning Optical Microscope

Abstract

The recent advances in chip-size microscopy based on optical scanning with spatially resolved nano-illumination light sources are presented. This new straightforward technique takes advantage of the currently achieved miniaturization of LEDs in fully addressable arrays. These nano-LEDs are used to scan the sample with a resolution comparable to the LED sizes, giving rise to chip-sized scanning optical microscopes without mechanical parts or optical accessories. The operation principle and the potential of this new kind of microscope are analyzed through three different implementations of decreasing LED dimensions from 20 µm down to 200 nm.

Individually Switchable InGaN/GaN Nano-LED Arrays as Highly Resolved Illumination Engines

“…The setup is shown schematically in Figure 7, with the LED array on the bottom, the test pattern (in the figure a single metallic square) in the middle and the detector board on top. Details on the microscope can be found in [29,30].…”

Fluorescence Multi-Detection Device Using a Lensless Matrix Addressable microLED Array

“…The driver can operate up to 10 V, thus allowing the LED to provide high optical power (~30 µW at 6 V [ 51 ]). The capability of these drivers to generate driving voltages up to 10 V also enables the circuit to be used to drive nanoLEDs [ 54 ], which usually work at a higher voltage bias [ 55 ] because of the high resistance associated with the interconnection of the LED with the CMOS [ 54 ]. In the matrix addressing LED array of this work, the driver can turn off an LED in 2 ns ( Figure 4 ), thus allowing this circuit to be used in time-resolved fluorescence.…”