Fast measurement of the thickness and group refractive index distribution of solid plates by line-field dispersive interferometry.

Real-time measurement of the thickness and group refractive index is crucial for semiconductor devices. In this paper, we proposed a fast synchronous method for measuring the thickness and group refractive index distribution of solid plates based on line-field dispersive interferometry. The proposed method measured the line-field distribution in an illuminated region through a single step.

Overexpression of chromodomain helicase DNA binding protein 5 (CHD5) inhibits cell proliferation and induces cell cycle arrest and apoptosis in chronic myeloid leukemia.

Background: Chromodomain helicase DNA binding protein 5 (CHD5) was reported to be a tumor suppressor and our previous work showed CHD5 was epigenetically inactivated in human chronic myeloid leukemia (CML). This study aimed to investigate the effect of its overexpression on CML tumorigenesis.

Methods: Quantitative reverse-transcriptase PCR and Western blotting analysis were used to detect the expression of CHD5 in human CML cell lines.

Multi-color method for the self-correction of the air refractive index.

We propose a multi-color method for the self-correction of the air refractive index based on the dispersive interferometry of an optical frequency comb. This method can be applied to correct the air refractive index for long-distance measurements in moist air. Optical lengths of multiple wavelengths were obtained simultaneously by the dispersive interferometry of an optical frequency comb.

Compression-coding-based surface measurement using a digital micromirror device and heterodyne interferometry of an optical frequency comb.

We propose a compression-coding-based surface measurement method that combines single-pixel imaging and heterodyne interference using an optical frequency comb. The real and imaginary parts of the heterodyne interference signals are used to obtain the depth information rapidly. By optimizing the ordering of the Hadamard measurement basis, we reconstruct a three-step sample with heights of approximately 10, 20, and 30 µm without an iterative operation in 6 ms, with a precision of 5 nm.

Chromodomain Helicase DNA-Binding Protein 5 Inhibits Renal Cell Carcinoma Tumorigenesis by Activation of the p53 and RB Pathways.

Chromodomain helicase DNA-binding protein 5 (CHD5) plays a crucial tumor suppressor role in multiple types of tumors. For this study, we investigated its clinical significance and the molecular mechanism(s) underlying tumorigenesis in renal cell carcinoma (RCC). Initially, CHD5 expression was assessed in primary tumor tissue and in tissue array.

Large-field step-structure surface measurement using a femtosecond laser.

We present a femtosecond laser-based interferometry for step-structure surface measurement with a large field of view. A height axial scanning range of 348 µm is achieved by using the method of repetition frequency scanning with reference to the Rb atomic clock and the optical path length difference design for 21 times of the pulse interval. A combined method, which includes the envelope peak positioning method for rough measurement, synthetic-wavelength interferometry for connection, and carrier wave interferometry for fine measurement, is proposed to reconstruct the surface.

Simplified phase-stable dual-comb interferometer for short dynamic range distance measurement.

A simplified phase-stable dual-comb interferometer for absolute distance measurement within a short dynamic range is proposed in this paper. The experimental results demonstrate that stable phase-difference information and lower timing jitter can be obtained within a time delay of 2000 ns between the reference interference signal and measurement interference signal. Using the proposed technique, the time-of-flight (TOF) result can link directly to the carrier-wave interferometric (CWI) result in an average time of 20 ms and can reach 2 nm precision in 0.

Femtosecond laser-based phase-shifting interferometry for optical surface measurement.

This paper demonstrates an unequal-path phase-shifting interferometer for precise optical surface measurement using a femtosecond laser. According to the periodic low temporal coherence of the femtosecond laser, the relative time delay between pulses from the reference and target surfaces is scanned by sweeping the repetition frequency for phase shifting when the optical path length difference is set to integer times of the pulse interval, which removes mechanical scanning devices in the interferometer. In particular, we employ an iterative least-squares fitting algorithm to derive the phase.

Synthetic wavelength interferometry of an optical frequency comb for absolute distance measurement.

We present a synthetic-wavelength based heterodyne interferometer of optical frequency combs with wide consecutive measurement range for absolute distance measurement. The synthetic wavelength is derived from two wavelengths obtained by two band-pass filters. The interferometric phase of the synthetic wavelength is used as a marker for the pulse-to-pulse alignment, which greatly improves the accuracy of traditional peak finding method.

Stabilizing carrier-envelope offset frequency of a femtosecond laser using heterodyne interferometry.

We propose a time-domain f stabilization method of a femtosecond laser using heterodyne interferometry. A femtosecond pulse train that is delayed by a spatial delay line interferes with the original pulse train. The phase difference between heterodyne interference signals extracted from different spectral regions is used to stabilize the relative position of the two pulse trains; then the heterodyne interference phase is used to stabilize the carrier-envelope offset frequency f.

Parameter optimization of a dual-comb ranging system by using a numerical simulation method.

Dual-comb system parameters have significant impacts on the ranging accuracy. We present a theoretical model and a numerical simulation method for the parameter optimization of a dual-comb ranging system. With this method we investigate the impacts of repetition rate difference, repetition rate, and carrier-envelope-offset frequency on the ranging accuracy.