Transcript ISO 10110 Optical Drawing Standards

ISO 10110 Optical Drawing
Standards
Introduction to Opto-Mechanical Engineering
OPTI 521
University of Arizona, College of Optical
Sciences
Jason Lane
13 December 2009
ISO 10110
• What is it?
• ISO standard describing preparation of drawings for optical elements and
systems
• Describes features unique to optical components – builds on GD&T
standards (compatible with ASME Y14.5M)
• ISO version of ASME Y14.18M (which will likely be superseded by ISO
10110 or some equivalent).
• Who uses it?
• Almost all of the optical design / manufacturing industry. Both
internationally and in the U.S. All of the major optical design packages
output ISO 10110 compliant element drawings.
• Why do we care?
• GD&T alone will not help you interpret an optical element or system
drawing. ISO 10110 is essential, and ISO compliant drawings will be
encountered 99.99% of the time. For example ….
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What do we do with this?
This is a typical
single element
ISO 10110
compliant
drawing
We will be able
to interpret this
drawing at the
end of the
presentation.
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ISO 10110 consists of 13 Optical
Drawing Parts
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
General – Differences between optical and mechanical drawings
Material imperfections – Stress birefringence – 0/
Material imperfections – Bubbles and inclusions – 1/
Material imperfections – Inhomogeneity and striae – 2/
Surface form tolerances – 3/
Centring tolerances – 4/ (note British English spelling .. Standard for ISO)
Surface imperfection tolerances – 5/
Surface texture
Surface treatment and coating
Table representing data of a lens element
Non-toleranced data
Aspheric surfaces
Laser irradiation damage threshold
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Material Imperfections
10110-2 thru 10110-4
•
•
•
2. Stress birefringence – 0/X, where X is maximum birefringence in nm/cm
3. Bubbles and Inclusions – 1/NxA, where N is number of permissible inclusions,
and A is length of the side of a square in mm. A2 is area that the bubble / inclusion
obscures.
4. Inhomogeneity and striae – 2/A;B
– A is class number for inhomogeneity (variation in index of refraction from nominal for
(usually) the melt where the element came from)
– B is class for striae (variations in index of refraction inside the element)
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Surface form Tolerances
ISO 10110-5
• 5. Surface form tolerances - 3/A(B/C)
– A is maximum spherical sag error from test plate
– B is the p-v maximum irregularity
– C is maximum rotationally symmetric p-v figure error
(best fit aspheric surface)
– Units are fringes (one half wavelength, standardized at
546.07 nm).
– RMS specification for fringes can be used.
• Example: 3/4(1): sag tolerance of 4 fringes, p-v
irregularity no greater than 1 fringe.
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Centring and surface imperfection tolerances
ISO 10110-6 & 10110-7
• 4/α, where α is the angle between the datum and the surface
(wedge angle)
• 7. Surface imperfection tolerances - 5/NxA. Treated similar to that
of Part 3. Coating imperfections preceded by a C, long scratches
preceded by an L, and edge chips by an E.
• Examples: 5/NxA; CN’xA’;LN”xA”,EA’”. A’” is the chip protrusion
from the edge.
7
Surface Texture (Polish and Grind)
ISO 10110-8
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Surface Treatment and Coatings
ISO 10110-9
• Can be indicated one of two ways as shown in the figure below.
• Fill in the box according to ISO 9211 –
– Very important 4-part standard describing coatings specifications
– Nothing comparable in ASME/ANSI world
• Example would be T = 0.9 for 450 < λ < 750.
• Could also refer to a graph indicated elsewhere in the drawing
• Could also refer to manufacturer’s coating trade name
• Also indicate a surface to be cemented.
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Compiling data in tabular form
ISO 10110-10
• Can become cluttered for simple element drawings. Tabular
form provides simpler method of presenting information to
avoid ambiguity and errors in reading
• Major optical design programs have adopted presenting ISO
10110 data in tabular form
– ZEMAX - used by Navy
– Code V - used by Raytheon (among others)
• This will be most common drawing form encountered
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Tabular Form example
ISO 10110 compliant drawing as generated by Zemax prior to filling out information
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Non-toleranced Data
ISO 10110-11
• ISO 10110 standardizes
tolerances when not
called out.
• “Default” tolerances
• Entirely different than
“shop tolerances” of
ASME Y14’s.
• WARNING: Tolerances are
very loose and may lead
to undesirable
consequences if not
carefully considered.
• Note that tolerances
scale with size of parts –
a European practice
rarely seen in U.S.
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Specifying Aspheres
ISO 10110-12
• Similar to procedure as for ordinary surfaces
• Exceptions:
– Surface type is called out clearly “asphere” or by type of
asphere for standard types
– Equation which describes the surface is given in a note.
– Slope tolerance (rate of change in surface sag) and
sampling length should be specified)
– Datums defined differently than in ISO 5459 (the GD&T
ISO) due to fact that aspheric surfaces are located
mechanically during fabrication and when mounting. If
alternate datum is desired, a note on the drawing should
be included
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Laser Damage Thresholds
ISO 10110-13
• Indication is given by
•
•
•
•
•
•
•
•
– 6/Hth; λ; pdg; fp; nTS x np for pulsed lasers
– 6/Eth; λ; nTS for continuous lasers.
“6/” is the indication for laser damage specification.
λ is the wavelength of the laser.
“pdg” is the pulse duration group number from ISO 11254
“fp” is the pulse repetition rate in Hz
“nTS” is the number of test sites on the sample surface
“np” is the number of laser pulses applied to each site.
Hth is expressed in terms of maximum energy density (J/cm2)
Eth is the maximum power density (W/cm2) for continuous tests.
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Returning to our ISO 10110 drawing…
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Explanation for the callouts on the
preceding drawing
Specifications
Value
Notes
R1, R2
Center Thickness
Material
Lens diameter
Clear (Effective) Aperture
Stress birefringence
Bubbles and inclusion
58.6 / 277
5
N-SK15 or equivalent
25 +0.01/-0
22.5 +0.1 / - 0
0/5
1/1x0.1
Tolerances are +/- 0.15 for R1, +/- 0.8 for R2
Default tolerance (+/- 0.2)
Inhomogeneity and Striae
2/2:3
Surface form error for both
surfaces
3/0.25(0.2/0.125)
Centering error
Surface form error
4/0.3’
5/5x0.05;L1x0.001;E0.5
Laser damage threshold
0.5 J/cm2
AR coating
T > 90% for spectral band
from 450 to 750 nm
Maximum OPD is 5nm/cm
Allow up to 1 inclusion, no larger than 100 um in size, over clear
aperture
Homogeneity class 2 is +/-5e-06
Striae class 3 is < 2%
0.25 fringe of sag (power) error
0.2 fringe of irregularity error
0.125 fringe of symmetric irregularity error
Element wedge is 0.3 arc minute
Allow up to 5 digs, each no larger than 50 um in size, over the clear
aperture
Allow 1 additional long scratch, no wider than 1um and longer than
4mm over the optical clear aperture
(this is a 10-5 scratch/dig spec)
Allow 1 edge chip no larger than 0.5 mm. Polish out all edge chips
λ=1053 nm
3 ns FWHM Gaussian pulse
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References for further information
• Tutorial on ISO 10110 Optical Drawing Standards, Jason Lane.
Tutorial white paper which accompanies this presentation
(lists all the ISO standards relating to optics and optical
systems). See me for copy.
• ISO 10110 Optics and Optical Instruments – Preparation of
drawings for optical elements and systems: A User’s Guide by
Ronald K. Kimmel and Robert E. Parks
• The ISO 10110 standards themselves (and ISO 9211)
• SPIE regularly hosts ISO 10110 short courses taught by David
M. Aikens. Available on spie.org website
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