||Reflecting and grazing incidence type mirrors
||Dimensions up to 1200 mm
||Typical surface accuracy is λ/15 at 633 nm P-V (λ/70 RMS)
Parabolic mirrors are most common type of aspherical mirrors
used in optical systems and devices. They are free from spherical
aberrations, and therefore focus the beam to a point or point
source to infinity.
OAP parameter description:
• Parent focal length (PFL) is the focal
length of the parent paraboloid
Y2=2pX for YX coordinates.
• Slant Focal Length (SFL) is the
distance between OAP mechanical
center and parabola focus F(p/2;0).
This parameter is commonly
known as Reflected Effective Focal
• Optical Centerline is the line parallel
to parent parabola optical axis and
coming through the mechanical
center of OAP.
• Zonal Radius (ZR) is the distance
between parent parabola optical axis
and optical centerline of the OAP.
Often are used Off Axis Angle -β.
• Off-axis Distance (OAD) is the
distance from parent parabola
optical axis to inner edge of OAP. This
value may be calculated from
ZR and vice versa.
All above parameters are not independent.
For example longer focal length influences
better surface accuracy and on opposite
site - longer zonal radius makes for lower
|Material||Zerodur, Astrositall, FS, ULETM , Si, Pyrex, BK7|
|Wavelength range, nm||9 - 200|
|Dimensions, mm||up to 500|| up to 1200|
|Clear Aperture (CA)||<90%||up to 100%|
|Focal length tolerances||±0.5%||±0.01%|
|Micro-roughness, nm (RMS)||~2||≤0.4|
|Slope Error, arcsec (RMS)||1 - longtitudal, 4 - transverse||0.3 - longtitudal, 0.8 - transverse|
|Shape accuracy @ 632.8 nm||≤λ/30||λ/100||