Current Projects
1) Nanophotonics
2) MEMS Spectrometer
3) MEMS Grating Scanner
4) Optical Microfluidic Systems
5) Diamond Turning Micromirrors
6) MEMS DAC
7) MEMS Micromirror
|
|
Nano-Photonics
Considering the technology that allows interactions of electromagnetic field in the nano-meter-sized eleme nts in the optical near field arena that is free from diffraction limits and highly dispersive. Conventional photonics that utilizes total internal reflection to propagate light utilizes the exotic GaAs or InP are rather limited by the light scattering, bulky materials, expensive fabrication. Where instead nano-photonics can enable the transmission in crystaline structures- namely Photonic Crystals by utilizing Bloch Wave Vectors to transmit light at a lossless mode , high bandwidth and multiple wavelength. Another example would be the physical threshold of the Moore's Law where cramming more transistors and into integrated circuits physically limited by the extreme heat dissipation and transmission speeds of electrons itself. Nano-photonics may just be the answer to replace tomorrow's computer processor
|
|
Read more...
|
|
In general, Fourier transform infrared (FTIR) spectroscopy works by passing infrared radiation through a sample and measure the output spectrum result. The FFT analysis of the spectrum reveals accurately the identities of the different materials in the sample and also their relative concentration. Hence FTIR is a common tool used in chemical analysis. Conventional FTIR require a mirror-scanning mechanism which makes machines complex, bulky and expensive. Thus, there is always a motivation to fabricate a smaller and lighter spectrometer with relatively good performance and at a low cost. A micro lamellar grating Fourier transform infrared spectroscopy (FTIR) which has been designed in-house and fabricated using surface micromachining process (MUMPS) seems to have offered the solution.
|
|
Read more...
|
|
|
MEMS Grating Light Modulator |
Optical Applications of MDAC: Grating Light Modulator
Grating light modulator driven by a 6-bit MDAC mechanism
|
|
Read more...
|
|
|
In recent years, microelectromechanical systems (MEMS) based optical scanners have attracted much attention because of their outstanding advantages compared to conventional macro-scanners such as rotating polygons, galvanometric and resonant optical scanners. These advantages include having a low mass, high scanning frequency, low power consumption, and potentially lower per unit cost through batch fabrication. MEMS optical scanners have the potential not only to provide significant performance enhancements such as small-size, high-speed, and low-cost to existing applications such as barcode readers, laser printers, scanning laser confocal microscopy systems and laser markers, but also to form the technological basis for a wide range of new applications in raster-scanning retinal projection displays, endoscopic optical coherence tomography and compact high-speed fiber optic components.
|
|
MDAC Application: Micromirror Array
 Micromirror Array implementation
Micromirror Array schematic
|
|
Read more...
|
|
|
As a result of the miniaturization trends in science and technology, there is an increasing demand for ultra-high precision positioning devices that can move in one or several degrees of freedom with nanometer displacement resolution and nanometer positioning repeatability. A novel micromechanical digital-to-analog converter (MDAC) mechanism for open-loop high-precision positioning applications has been developed. The MDAC mechanism consists of a movable stage, an array of two-state (ON/OFF) microactuators, and set of suspension springs for both in-plane and out-of-plane motion including rotation. with binary-weighted stiffness. The developed mechanism has a number of outstanding advantages including, low-cost, open-loop, simple driving electronics, input voltage noise immunity, good repeatability, and easy of implementation.
Overview of MDAC developments
Schematic of MDAC
Schematic for out-of-plane MDAC
A 4-bit MDAC mechanism has been successfully designed and fabricated for out-of-plane translational motion, achieving a total stroke of 675 nm (full-scale output) and step size (LSB) of 45 nm in a highly repeatable and stable manner.
|
|
Read more...
|
|
|
Research 
