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We present a new design for the integration of a tunable Fabry–Perot (FP) filter and the grating etched on top of the cavity (IGFP) in the miniature spectrometer. It is based on the predispersion of the grating with the capacity of spatial separation of the spectral component and filter effect of the tunable FP filter. The free spectral range (FSR) of the IGFP is determined by the FSR of the grating, and its resolution depends on the filtering capacity of the FP filter. In the experiment, the high-resolution and wavelength scanning process of the IGFP were demonstrated with a narrowband and broadband light source, respectively. The results of the sub-nanometer resolution agree well with those from a commercial optical spectrum analyzer. Further, the IGFP provides an effective approach to solve the problem of the decrease of spectral resolution in the miniaturization process.

A profile formation and control approach has been developed for manufacturing micro-optical elements with continuous profile and deep relief depth. Based on Dill’s exposure model, an effective expression for determining the exposure dose function is established by using a supposition of equivalent exposure threshold inside a resist layer. An analytical simplified formula is further deduced by taking absorbance as constant B, and the approximate condition is discussed. For evaluating the simplified formula, the profile error was calculated and analyzed by simulation. With the exposure dose function, the binary mask for manipulating the light distribution by means of a moving-mask lithographic method can be designed. Experimental results are given and show the comparative performance to the required profile and relief depth. A series of refractive microlens arrays with aspherical profiles, a wide range of numerical apertures (0.005 to 0.6), and high fill factors were accomplished in the lab and may be applied to many systems. © 2004 Society of Photo-Optical Instrumentation Engineers.

A new photolithographic technique that combines the advantages of a programmable digital liquid crystal display (LCD) system and projection photolithography system to fabricate arbitrarily shaped microstructures using LCD panels as real-time masks is reported. Its principle and design method are explained. Based on a partial coherent imaging theory, the process to fabricate microaxicon arrays and zigzag gratings is simulated. The experiment has been set up using a color LCD as a real-time mask. Microaxicon arrays and zigzag gratings have been fabricated by a real-time photolithographic technique. The 3-D surface relief structures are made on panchromatic silver-halide sensitized gelatin (Kodak-131) with trypsinase etching. The pitch size of the zigzag grating is 46.26 m, and the etching depth is 0.802 m. The caliber of the axicon is 118.7 m, and the etching depth is 1.332 m. © 2003 Society of Photo-Optical Instrumentation Engineers.

Discrete formulas to calculate aerial imaging on the wafer for photolithography are presented, and physical fundamental of inverse Fourier transform convolution filtering to improving resolution is discussed. The larger contrast for dense L/Sgroup with the pitch of 0.27 m is obtained with an ArF 193 nm stepper with a numerical aperture of 0.60 and partial coherent coefficients of 0.3. © 2000 Society of Photo-Optical Instrumentation Engineers.

An innovative beam-shaping method for laser diode stacking is presented by employing a pair of reflective two-wedge-angle prism arrays. Each subprism with two variable wedge angles is designed for deflecting the partial emission from different bars to the dead spaces of the stack, according to the configuration of the real laser diode (LD) stack and the requirement of the system. The formula to determine the parameters of each subprism is deduced by way of geometrical analysis. A beam-shaping system for stack laser diodes with three bars is designed and simulated, and the results show that the stack laser beam is well transformed into a required distribution efficiently. © 2005 Society of Photo-Optical Instrumentation Engineers.