Calibration of a Shack–Hartmann sensor for absolute measurements of wavefronts

Чернышов, А. К.; Sterr, U.; Riehle, F.; Helmcke, J.; Pfund, Johannes

doi:10.1364/ao.44.006419

Cited by 60 publications

(21 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As shown in Fig. 1(a), for the kth aperture at a distance, r k ¼ ka, from the optical axis where a is the aperture size of each microlens, the shift is related to the wavefront slope over the subaperture by [10,11] …”

Section: Theorymentioning

confidence: 99%

Strain and tilt measurement using multi-point diffraction strain sensor

Wang

Zhou

Lim

et al. 2008

Optics & Laser Technology

View full text Add to dashboard Cite

Section: Theorymentioning

confidence: 99%

Strain and tilt measurement using multi-point diffraction strain sensor

Wang

Zhou

Lim

et al. 2008

Optics & Laser Technology

View full text Add to dashboard Cite

“…In this group of sensors a trade-off is seen between high phase resolution versus high spatial resolution which is limited by the size of the lenslet-array and the number of lenses. The phase resolution that can be obtained with these sensors ranges λ/100 for an Ø6 mm beam diameter to λ/500 for Ø1 mm at λ 632.8 nm [16]. More recent research [17] showed measurement sensitivity up to λ/15500 at λ 820 nm, though the spatial resolution is again limited by a 30x30 lenslet-array over 12.5x12.5 mm.…”

Section: Introductionmentioning

confidence: 99%

Relative optical wavefront measurement in displacement measuring interferometer systems with sub-nm precision

Meskers¹,

Voigt²,

Spronck³

2013

Opt. Express

View full text Add to dashboard Cite

Many error sources can affect the accuracy of displacement measuring interferometer systems. In heterodyne interferometry two laser source frequencies constitute the finally detected wavefront. When the wavefronts of these source frequencies are non-ideal and one of them walks off the detector, the shape of the detected wavefront will vary. This leads to a change in measured phase at the detector resulting in increased measurement uncertainty. A new wavefront measurement tool described in this publication measures the relative phase difference between the two wavefronts of the two source frequencies of a coaxial heterodyne laser source as used in commercial heterodyne interferometer systems. The proposed measurement method uses standard commercial optics and operates with the same phase measurement equipment that is normally used for heterodyne displacement interferometry. In the presented method a bare tip of a multimode fiber represents the receiving detection aperture and is used for locally sampling the wavefront during a line scan. The difference in phase between the beating frequency of the scanning fiber and a reference beating frequency that results from integration over the entire beam, is used for the reconstruction of the wavefront. The method shows to have a phase resolution in the order of ~25 pm or ~λ/25000 for λ 632.8 nm, and a spatial resolution of ~60 µm at a repeatability better than 1 nm over one week.

show abstract

“…A WFS is essential to any AO assisted imaging system. There are a few kinds of wavefront sensing techniques including spatially resolved refractometry [9], laser ray tracing [10], Shack-Hartmann wavefront sensing [11] and pyramid wavefront sensing [12]. All these techniques sample the aberrations transversally, though none of them can provide depth resolved wavefront information.…”

Section: Introductionmentioning

confidence: 99%

Time-domain coherence-gated Shack-Hartmann wavefront sensor

Wang

Podoleanu

2011

SPIE Proceedings

View full text Add to dashboard Cite

In the present paper we investigate the possibility of narrowing the depth range of a physical Shack -Hartmann wavefront sensor (SH-WFS) by using coherence gating. We have already demonstrated a low coherence interferometry (LCI) set-up, capable of generating similar spots patterns as a conventional SH-WFS and also capable of eliminating stray reflections. Here, we evaluate the accuracy of wavefront measurements using a coherence-gated (CG)/SH-WFS. This is based on a Mach-Zehnder interferometer combined with a SH-WFS, that implements time-domain (TD)-LCI acquisition. The wavefront measurement errors introduced by the non-uniform distribution of the reference power over the photo-detector array were investigated. The effect on the centroid nodes accuracy due to different numbers of phaseshifting interferometry (PSI) steps applied was also evaluated. This novel technique has the potential of providing depth resolved aberration information, which can guide better correction in adaptive optics assisted OCT and confocal imaging instruments.

show abstract

Calibration of a Shack–Hartmann sensor for absolute measurements of wavefronts

Cited by 60 publications

References 16 publications

Strain and tilt measurement using multi-point diffraction strain sensor

Strain and tilt measurement using multi-point diffraction strain sensor

Relative optical wavefront measurement in displacement measuring interferometer systems with sub-nm precision

Time-domain coherence-gated Shack-Hartmann wavefront sensor

Contact Info

Product

Resources

About