A zero-order waveplate is an optical retarder that has a total
phase retardation of less than 360° (2π). When using the optical
path difference (Δ) to represent the phase retardation, it is
defined as 0 < Δ < λ. Compared to low-order and multi-order
waveplates, where Δ = (m + δm)λ with m = 1, 2, 3, ..., and 0 < δm < 1,
the zero-order waveplate exhibits reduced sensitivity to variations
in temperature and wavelength.
Optocity make different types of zero-order waveplates: classical compound
zero-order waveplates and true zero-order waveplates. The classical compound
zero-Order waveplates are made from two multiple-order plates with slightly
different thicknesses, either cemented, optically contacted or air-spaced.
The slow axis of one waveplate is aligned with the fast axis of the other. The
difference in thickness is chosen to achieve the required net phase change.
This type of zero order waveplate can function across a broad wavelength
range with low temperature sensitivity. The true zero-order waveplates are
single thin plate where the optical phase delay between the two polarizations
is exactly 90° for a quarter waveplate and 180° for a half waveplate.
Features of Zero-order Waveplate
- Low temperature sensitivity
- Wide spectral bandwidth
- High damage threshold(air-spaced)
- Large sizes available
Multi-order waveplates, classical zero order waveplates and true zero order waveplates are
generally interchangeable for most of applications. However, for certain critical applications,
the use of a zero-order waveplate should be prioritized. The advantages of zero-order
waveplates include an increased bandwidth and reduced sensitivity to temperature
Variations.
In situations requiring wide field angle acceptance, true zero-order waveplates
represent the optimal choice. The classical two plates design zero order waveplate has
a relatively larger thickness which reduces the field angle. For the
applications where a large field angle is necessary, such as imaging systems, true zero order waveplate
gives the solution. These true zero order waveplates are made of a very thin plate
or cemented with a BK7 substrate, which ensures the best possible field
angle, temperature and wavelength performance.
The following table gives the comparison of low order waveplate, classical zero order waveplate
and true zero order waveplate(based on 1/2 @1064nm with 1/100 retardation variation):
Type of Waveplate
Multi-Order
Classical zero-order
True zero-order
Temperature Sensitivity (nm/°C)
0.05
0.006
0.006
Spectral Bandwidth (nm)
6.1
42.6
42.6
Acceptance Angle (deg.)
8
4
23
Specifications of zero order waveplate
Material:
Premium-grade quartz
Dimension Tolerance:
+0.0/-0.1mm
Parallelism:
<1 arc second
Surface Quality:
20-10
Wavefront Distortion:
λ/8@633nm
Retardation Variation:
<λ/300 wave
Clear Aperture:
90% central
Coating:
AR-coating R<0.1%
Damage Threshold:
>500 MW/cm² 1 ns 1064 nm
Mount:
Optional
Wavelength:
Custom design available.
Common used wavelengths: 355nm, 400n, 515nm, 532nm,
633nm, 670nm, 700nm, 780nm, 795nm, 810nm, 830nm, 852nm, 895nm, 920nm,
980nm, 1030nm, 1047nm, 1064nm, 1310nm, 1342nm, 1480nm, 1550nm, 1590nm, 1800nm and more.
OptoCity offer the highest quality zero-order quarter waveplates and half waveplates at
very competitive price. Standard zero-order waveplates are available in stock. OEM micro
size waveplates, custom design including optical axis mark are available upon request.
