Dual wavelength digital holography for improving the measurement accuracy

In dual wavelength digital holography, a synthetic wavelength is obtained by using two lasers with different wavelengths to expand the measurement range of samples’ step heights from nanometers to micrometers. However, its measurement accuracy reduces along with the expansion of measuring range and significant noise is introduced at the same time. For cases where the sample’s height is smaller than the wavelength of illumination light, the measurement accuracy is very important. In this paper, a new approach of dual wavelength digital holography is presented. The synthetic wavelength is smaller than the wavelength of the two different lasers. Higher measurement accuracy can thus be achieved. The analysis and experimental results show the validity of this method.

[1]  Dayong Wang,et al.  Three-dimensional imaging of microstructure by dual-wavelength digital holography , 2011, Other Conferences.

[2]  Anand Asundi,et al.  Physical spherical phase compensation in reflection digital holographic microscopy , 2012 .

[3]  Alejandro Restrepo-Martínez,et al.  Simultaneous dual-wavelength reflection digital holography applied to the study of the porous coal samples. , 2008, Applied optics.

[4]  Jianlin Zhao,et al.  High resolution digital holographic microscopy with a wide field of view based on a synthetic aperture technique and use of linear CCD scanning. , 2008, Applied optics.

[5]  A Finizio,et al.  Quantitative Phase Microscopy of microstructures with extended measurement range and correction of chromatic aberrations by multiwavelength digital holography. , 2007, Optics express.

[6]  A. Asundi,et al.  Time-averaged in-line digital holographic interferometry for vibration analysis. , 2006, Applied optics.

[7]  Jianlin Zhao,et al.  Real-time visualization of Karman vortex street in water flow field by using digital holography. , 2009, Optics express.

[8]  Jianlin Zhao,et al.  Recording and reconstruction of a color holographic image by using digital lensless Fourier transform holography. , 2008, Optics express.

[9]  Jianmin Miao,et al.  Dynamic characterization of MEMS diaphragm using time averaged in-line digital holography , 2007 .

[10]  Yingjie Yu,et al.  Characterization and inspection of microlens array by single cube beam splitter microscopy. , 2011, Applied optics.

[11]  Chi Zhang,et al.  Dual wavelength digital holography phase unwrapping by linear regression , 2011, Defense + Commercial Sensing.

[12]  Jianlin Zhao,et al.  Phase aberration compensation of digital holographic microscopy based on least squares surface fitting , 2009 .

[13]  Etienne Cuche,et al.  Real-time dual-wavelength digital holographic microscopy with a single hologram acquisition , 2007 .

[14]  Christian Depeursinge,et al.  Simultaneous cell morphometry and refractive index measurement with dual-wavelength digital holographic microscopy and dye-enhanced dispersion of perfusion medium. , 2008, Optics letters.