Equations
From HoloWiki  A Holography FAQ
Revision as of 15:05, 12 May 2013 by
Jsfisher
(
talk

contribs
)
(
diff
)
← Older revision
 Latest revision (diff)  Newer revision → (diff)
Jump to:
navigation
,
search
Contents
1
Common DOE surfaces
1.1
Sinusoidal, triangle
1.2
Square, rectangle
1.3
Blazed, sawtooth
2
Holographic Deflectors (hologons)
Common DOE surfaces
Sinusoidal, triangle
Max D.E. ~ 30% ± 1 order
Power distribution follows Bessel function in the scaler region.
T ≈ λ for transmission.
T ≈ λ/4 for reflection.
Easily replicated or deep etch can yield higher efficiency.
Square, rectangle
Max D.E. ~ 40% ± 1 order.
Power distributions favors odd orders.
Pi phase shift typical.
Classic binary grating.
T ≈ λ for transmission.
T ≈ λ/4 for reflection.
Blazed, sawtooth
Max D.E ~ 98%
Reflection Case:
λ = 2 d sin a
T = λ/2 ± 10%
Transmission Case:
λ = d sin b
a ≈ 2b
T = λ/(n1) ± 10%
Surface shadows reduce D.E. by
$\textstyle {\frac {\lambda ^{2}}{nd^{2}}}$
Wavelength changes reduce D.E. by
$\textstyle \left({\frac {\pi \Delta \lambda }{b\lambda }}\right)^{2}$
Holographic Deflectors (hologons)
N = θD/(1.4λ)
N = number of resolvable spots
θ = full scan angle in radians
D = beam diameter in microns
λ = wavelength
Φ = wedge angle of glass
Special case of linear scan and near wobble invariance a ~ b ~ 45° max straight scan angle ~ 36°
Dynamic wobble
$\scriptstyle \simeq \Delta \Omega /128$
Wedge wobble = (n1)Φ
Scan angle multiplier = 1.4 @ 90° cross scan angle
Last modified on 9/29/97
Category
:
Rallison
Navigation menu
Personal tools
Log in
Namespaces
Page
Discussion
Variants
Views
Read
View source
View history
More
Search
Navigation
Main page
Recent changes
Random page
Help
Tools
What links here
Related changes
Special pages
Printable version
Permanent link
Page information