PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.
This pdf file contains the front matter associated with SPIE Proceedings Volume 7793, including Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Miniature camera lenses are currently manufactured at volumes over 1 billion units per year. In this high volume
industry, design methods that improve tolerance to manufacturing errors result in improved yield and significantly
reduced cost. Few, if any, design for manufacture methods have been developed for this solution space, which is vastly
different than traditional design as it is dominated by highly aspheric optics and compact design forms. In this paper, five
design for manufacture methods that were developed for traditional designs are examined for their efficacy in improving
the as-built performance of a well-corrected injection molded miniature camera lens. Building on the results of the
evaluation, a new design for manufacture method is developed which is highly correlated to the sensitivities associated
with this solution space and requires little computational overhead. The new method generates 1.3 times the number of
improved solutions and produces a design with 1.7X looser tolerances than the starting point.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
A specialty area in the commercial photographic industry involves simultaneously producing a plurality of high-quality photographs of varying size and shape from a single photographic negative or digital image. The images are formed on a large piece of photographic paper by a set of lenses having specific magnifications and appropriately located between the negative and paper. Package printers are typically reconfigurable to allow different sets of images to be created; however, such reconfiguration is time consuming. Most often, a package printer is configured and then devoted to a specific format. The case study presented in this paper covers the system requirements, design and fabrication of the various lenses, exposure and color balancing of the lenses, alignment and tolerancing. An interesting aspect of this package printer project was that the client literally built everything in-house including the mechanical housing, film and paper transports, lamp houses, lenses, and coatings. A critical element of the design, fabrication, and assembly of these package printers was tolerancing. Since a large number of these package printers was to be manufactured for their in-house, management needed assurance that the unit could be reasonably manufactured and would be reliable in the several plants around the world. The emphasis of this case study is on the challenge of producibility which required close attention to the capabilities of the various fabrication groups, assemblers, and technicians employed by the client. The project was successful and untold billions of photographs have been made by these package printers.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The concept of centering a precision, symmetric lens system using a high-quality rotary table and an auto-focusing test
instrument are well known. Less well known are methods of finding convenient, or easily accessible, lens conjugates on
which to focus while performing the centering operation. We introduce methods of finding suitable conjugates and centering
configurations that lend themselves to practical centering solutions.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
James Webb Space Telescope Alignment and Metrology
In this paper, simple relationships are presented to determine the amount of focal shift that will result from the axial
motion of a single element or group of elements in a system. These equations can simplify first-order optomechanical
analysis of a system. Examples of how these equations are applied are shown for lenses, mirrors, and groups of optical
elements. Limitations of these relationships are discussed and the accuracy is shown in relation to modeled systems.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The development of the James Webb Space Telescope (JWST) is an international collaboration led by NASA in
partnership with the European Space Agency and the Canadian Space Agency (CSA). The Canadian contribution to the
mission is the Fine Guidance Sensor (FGS). The FGS-Guider images two fields of view onto two detectors. For testing,
Optical Ground Support Equipment telescopes are used to simulate the image from the Observatory's Optical Telescope
Element. The FGS Engineering Test Unit (ETU) comprises 2 functioning Guider channels: one fully functional channel
with a Teledyne H2RG HgCdTe 5 micron cutoff detector, and another with an H2RG multiplexer in place of a detector.
This paper reports on the results of cryogenic vacuum testing of the alignment of the final ETU instrument configuration.
Images at ambient (from the H2RG multiplexer) and at cryo (from detector and H2RG multiplexer) were analysed to
determine best focus and FGS field of view at cryogenic temperatures. The ETU test results for best focus, tip/tilt of
focal planes, field of view location and size are well matched to the budgets and predictions and meet requirements for
the FGS-Guider.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The Optical Telescope Element (OTE) consists of a 6.6 m, all-reflective, three-mirror anastigmat. The 18-segment
primary mirror (PM) presents unique and challenging assembly, integration and alignment verification requirements.
Each mirror segment is mechanically integrated with the Primary Mirror Backplane Support Structure (PMBSS) using
compound angle shims to compensate for global alignment and local co-planarity errors. The processes used to
determine the mechanical shim prescription, primary mirror alignment and integration, and placement verification are
discussed. In an effort to reduce process uncertainty and program risk, the JWST program recently conducted a PMSA
Integration Demonstration at ITT. Through this activity, full scale demonstrations of the Ground Support Equipment
(GSE) and critical integration processes were successfully completed. The results of these demonstrations indicate that
the equipment, processes, and procedures developed by ITT meet the critical requirements for PMSA placement.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The James Webb Space Telescope (JWST) is a general astrophysics mission which consists of a 6.6m diameter,
segmented, deployable telescope for cryogenic IR space astronomy (~35K). The JWST Observatory architecture
includes the Optical Telescope Element and the Integrated Science Instrument Module (ISIM) element that contains four
science instruments (SI) including a Guider.
The alignment philosophy of ISIM is such that the cryogenic changes in the alignment of the SI interfaces are captured in
the ISIM alignment error budget. The SIs are aligned to the structure's coordinate system under ambient, clean room
conditions using laser tracker and theodolite metrology. The ISIM structure is thermally cycled and temperature-induced
structural changes are concurrently measured with a photogrammetry metrology system to ensure they are within
requirements.
We compare the ISIM photogrammetry system performance to the ISIM metrology requirements and describe the
cryogenic data acquired to verify photogrammetry system level requirements, including measurement uncertainty. The
ISIM photogrammetry system is the baseline concept for future tests involving the Optical Telescope Element (OTE) and
Observatory level testing at Johnson Space Flight Center.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The James Webb Space Telescope Integrated Science Instrument Module utilizes two fixtures to
align the Optical Telescope Element Simulator (OSIM) to the coordinate systems established on the
ISIM and the ISIM Test Platform (ITP). These fixtures contain targets which are visible to the OSIM
Alignment Diagnostics Module (ADM). Requirements on these fixtures must be met under ambient and
cryogenic conditions. This paper discusses the cryogenic metrology involving Laser Radar
measurements through a chamber window that will be used to link photogrammetry target measurements
used during ISIM structure cryogenic verification and the ADM targets, including evaluation of
distortion introduced from the window.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We characterize the precision of five approaches used to align a series of targets over a distance of two meters. For
many applications, an alignment telescope provides the necessary precision for positioning targets. However, for
systems with tight tolerances, we must have a measure of the uncertainties in the alignment telescope to determine if it
can truly meet the system requirements. We develop a procedure to measure the precision of each alignment approach
and compare their performances. We use a telescope constructed from off-the-shelf optics and mechanics to determine
if we can obtain alignment precision comparable to an alignment telescope of superior optical quality.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The National Ignition Facility will begin testing DT fuel capsules yielding greater than 1013 neutrons during 2010.
Neutron imaging is an important diagnostic for understanding capsule behavior. Neutrons are imaged at a scintillator
after passing through a pinhole. The pixelated, 160-mm square scintillator is made up of 1/4 mm diameter rods 50 mm
long. Shielding and distance (28 m) are used to preserve the recording diagnostic hardware. Neutron imaging is light
starved. We designed a large nine-element collecting lens to relay as much scintillator light as reasonable onto a 75 mm
gated microchannel plate (MCP) intensifier. The image from the intensifier's phosphor passes through a fiber taper onto
a CCD camera for digital storage. Alignment of the pinhole and tilting of the scintillator is performed before the relay
lens and MCP can be aligned. Careful tilting of the scintillator is done so that each neutron only passes through one rod
(no crosstalk allowed). The 3.2 ns decay time scintillator emits light in the deep blue, requiring special glass materials.
The glass within the lens housing weighs 26 lbs, with the largest element being 7.7 inches in diameter. The distance
between the scintillator and the MCP is only 27 inches. The scintillator emits light with 0.56 NA and the lens collects
light at 0.15 NA. Thus, the MCP collects only 7% of the available light. Baffling the stray light is a major concern in the
design of the optics. Glass cost considerations, tolerancing, and alignment of this lens system will be discussed.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The Advanced Technology Solar Telescope (ATST) is a 4m off-axis telescope with a Gregorian front end. At the
time of its construction it will be the world's largest solar astronomical telescope. During scientific operations
the ATST mirrors and structure will be deformed due to thermal and gravitational loading. The ATST team
has developed a quasi-static alignment scheme that utilizes the wavefront sensing signals from at least one and
as many as three wavefront sensors in the telescope science field of view, and active figure control of the primary
mirror and rigid body control of the secondary mirror to achieve least-squares optical control of the telescope.
This paper presents the quasi-static alignment model for the ATST, and three different active alignment schemes
that are the damped least-squares control, force optimized control that defines a least-squares aligned state of
the telescope subject to minimum primary actuator force, and pivot-point control of the secondary mirror. All
three strategies achieve the desired minimum RMS wavefront error, but demonstrate different optimized states
of the telescope.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We first studied the characteristics of alignment performances of two computer-aided alignment algorithms i.e. merit
function regression (MFR) and differential wavefront sampling (DWS). The initial study shows i) that, utilizing damped
least square algorithm, MFR offers accurate alignment estimation to the optical systems with non-linear wavefront
sensitivity to changes in alignment parameters, but at the expense of neglecting the coupling effects among multiple
optical components, and ii) that DWS can estimate the alignment state while taking the inter-element coupling effects
into consideration, but at the expense of increased sensitivity to measurement error associated with experiment apparatus.
Following the aforementioned study, we report a new improved alignment computation technique benefitted from
modified MFR computation incorporating the concept of standard DWS method. The optical system used in this study is
a three-mirror anastignmat (TMA) based optical design for the next generation geostationary ocean color instrument
(GOCI-II). Using an aspheric primary mirror of 210 mm in diameter, the F/7.3 TMA design offers good imaging
performance such as 80% in 4 um in GEE, MTF of 0.65 at 65.02 in Nyquist frequency. The optical system is designed to
be packaged into a compact dimension of 0.25m × 0.55m × 1.050m. The trial simulation runs demonstrate that this
integrated alignment method show much better alignment estimation accuracies than those of standard MFR and DWS
methods, especially when in presence of measurement errors. The underlying concept, computational details and trial
simulation results are presented together with implications to potential applications.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The Navy Prototype Optical Interferometer (NPOI) near Flagstaff, Arizona, makes use of separate smaller optical
elements spaced along a Y-array and used simultaneously to simulate an equivalent single large telescope. The
instrument is useful in generating and upgrading existing astronomical catalogues and investigating synthetic aperture
optical imaging techniques. The NPOI is a joint collaboration between the US Naval Observatory and Naval Research
Laboratory in collaboration with the Lowell Observatory. Stellar radiation (visible light) reflects off 35 cm diameter flat
mirrors, also known as siderostats, toward a tilt-tip mirror, which reflects a 12 cm diameter beam through a multi-reflection
relay transport system. To maximize the reflective area of the siderostat optics and achieve an increase by a
factor of 8.5 in light collecting area, a beam compressor is to be installed between the siderostat and fast tip/tilt mirror.
However, the present configuration of a prototype beam compressor mount (BCM) vibrates at unacceptable amplitudes,
which makes it nearly impossible to optically align the mirrors. This paper presents the results of finite element analyses
conducted to quantify the design limitations of the prototype beam compressor mount. The analyses indicated that the
current configuration is too soft, with very low fundamental frequencies, which verified the difficulties encountered
during alignment tests. Based on these results, design modifications have been proposed to increase the overall
structural stiffness of the mount and increase its fundamental frequency of vibration. These modifications will
mechanically stabilize the structure for the alignment of the optics, and allow integration of the compressor into the
interferometer. The interferometer will then have the capability to capture more light from each siderostat and allow
observations of fainter stellar targets. More generally, the results can be useful as a guide for engineers and scientists
involved in the design of similar optomechanical structures.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
Measurement of the distance to an object can be done in a number of ways based on system constraints such as minimum
or maximum range, range accuracy, measurement update rate, and system power, with a considerable variation in
resulting system complexity.
Active approaches used in laser rangefinders yield submillimeter accuracy in laboratory or survey exercises while time-of-
flight or flash LIDAR yields centimeter-scale range accuracy from mapping platforms in low Earth orbit. High
ranging sensitivity, in excess of one part in 106, can be achieved, but generally requires fairly sophisticated control of the
output pulse phase, shape, and energy, and also relies on fairly high speed pulse detection and processing.
Passive approaches based purely on parallax imaging can determine distances to centimeter accuracies over moderate
distances. The accuracy that can be achieved with this type of system is highly dependent on the overall SNR and the
parallax angle, with a range sensitivity of one part in 1000 being typical for this approach.
A low-cost passive range metrology system is described based on geometrical imaging with distance measurement
sensitivity to better than one part in 10,000. The approach uses knowledge of the relationship between features on the
target and the imaging parameters of the metrology camera, as in the parallax/centroid approach, but incorporates a
specific target encoding that optimizes the performance. Results are presented using a standard machine vision camera
in room ambient lighting conditions, showing a range sensitivity of 100 microns with a target-camera separation of 1200
mm.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
CdZnTe is a high efficiency, room temperature radiation detection material that has attracted great interesting in
medical and security applications. CZT crystals can be grown by various methods. Particularly, CZT grown with the
Transfer Heater Method (THM) method have been shown to have fewer defects and greater material uniformity. In this
work, we developed a proof-of-concept dual lighting NIR imaging system that can be implemented to quickly and
nondestructively screen CZT boule and wafers during the manufacturing process. The system works by imaging the
defects inside CZT at a shallow depth of focus, taking a stack of images step by step at different depths through the
sample. The images are then processed with in-house software, which can locate the defects at different depths, construct
the 3D mapping of the defects, and provide statistical defect information. This can help with screening materials for use
in detector manufacturing at an early stage, which can significantly reduce the downstream cost of detector fabrication.
This inspection method can also be used to help the manufacturer understand the cause of the defect formation and
ultimately improve the manufacturing process.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
ASSIST, The Adaptive Secondary Setup and Instrument STimulator, is being developed to provide a testing facility for
the ESO Adaptive Optics Facility (AOF). It will allow the off-telescope testing of three elements of the VLT AOF; the
Deformable Secondary Mirror (DSM) and the AO systems for MUSE and HAWK-I (GALACSI and GRAAL). The core
of ASSIST consists of a 2-mirror setup (AM1-AM2) allowing the on-axis test of the DSM in interferometric mode.
However, during the initial stages of ASSIST integration, DSM would not be present. This makes the task of aligning
AM1-AM2 to within an accuracy of 0.05mm/1 arcmin rather challenging. A novel technique known as Shack-Hartmann
method has been developed and tested in the lab for this purpose. A Shack Hartmann wavefront sensor will be used to
measure the mis-alignment between AM1-AM2 by recording the coma and astigmatism in the presence of large
spherical aberration introduced because of tilt/decenter of AM2 with respect to AM1. Thereafter, 20 optical components
including lenses, flat mirrors and beam-splitter cubes divided into five sub-assemblies should be aligned to AM1-AM2-
DSM axis which ultimately passes through the mechanical axis of large AMOS rotator.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
We use the profile of a parabolic mirror to calculate the scattered electromagnetic field, this mirror can be used
in the design and construction of a reflector telescope. We calculate the effect caused by the roughness on the
performance of this optical elements, the calculation is done within the Rayleigh approximation. In another work
presented in this meeting we show a comparison of the results obtained numerically using different roughness
parameters and calculate its effect on the aberrations of the wavefront.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
The following paper provides the practicing engineer with guidelines on the relationships between cost and various
performance factors for different types of linear stages. When multiple precise motions need to be made in a system,
stages are typically the solution. A number of factors should be considered before choosing a stage: cost, load capacity,
travel range, repeatability, resolution, encoding accuracy, errors in motion, stiffness, stability, velocity of motion,
environmental sensitivity, and additional features like over-travel protection and locking mechanisms. There are a
variety of different bearing types for linear stages, each with their own advantages and disadvantages. This paper
presents charts that provide relationships between the cost, travel range, angular deviation, and load capacity of various
types of manual one-axis linear stages. The stages considered were those that had less than a 2.5" travel range and sold
by major optomechanical vendors. The bearing types investigated were dovetail, flexure, ball bearing, double row ball
bearing, crossed roller bearing, and gothic arch ball bearing. Using the charts and general guidelines provided in this
paper, a more informed decision may be made when selecting a linear stage.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.