Very long range surveillance and target recognition applications in the infrared spectral range require optical lens
systems with large focal length and high numerical aperture optimized for low aberrations and stray light at a working
temperature considerably different from the temperature of mounting and adjustment of the system. Additionally, for the
airborne use the system shall be rugged, lightweight and compact. These conflicting requirements do not only represent a
demanding design task. The much bigger challenges consist in the selection and characterisation of the optical material,
in the fabrication and measurement of the particular optical elements, in their integration into the lens system as well as
in the characterisation of this lens system and in the verification of its performance parameters. Recent technological
approaches developed at JENOPTIK Laser, Optik, Systeme GmbH for the fabrication and the test of such lens systems
will be presented in this paper. It will be shown that an iterative combination of manufacturing and measurement
techniques is needed for the fabrication of IR lens systems meeting the highest performance requirements.
Aside from steppers also inspection systems in the semiconductor industry as well as in micro
material processing require DUV imaging optics with very high optical requirements.
A test and adjustments set-up based on the Shack-Hartmann wave front sensor for objectives
and telescopes is presented. It allows primarily to characterize the image quality of systems
under test for both finite as well as infinite object and image distances.
From the wave front the modulation transfer function, point spread function or encircled
energy data can be derived. Also, other data such as magnifications, focal lengths and even
distortion with micrometer accuracy can be obtained with the test bench.
The test system consists of a spherical waves generator, the sensor including adapting optics
and the mechanical motion system. It is highly motorized and all essential functions are
computer controlled. The available wavelengths currently range from NIR to 193nm.
We present an interferometrical setup and its application as a diameter measuring device in a machine tool. The optical setup is a folded Linnik interferometer. The proposed pen-like configuration is very space saving. The probing part of the sensor head fits bores from a diameter of 15 mm. The interferometer works with light of a short coherence length for unambiguous distance signals. The reference mirror is scanned by means of a tuning fork with a frequency of 1.1 kHz within a range of more than 0.2 mm. A design of a sensor head is given. The device can be fixed in the master chuck of a milling machine. The nominal diameter of the bores to be measured is preset to 40 mm, but it can be chosen from 20 mm to 55 mm using the given optical components by changing one internal distance. Measuring results show the capability of the device to analyze the position, the diameter and the shape of bores. The device can be used to establish a very fast quality control loop and therefore it will help to improve the efficiency of the production process.
A set-up based on a zoom stereo microscope is presented which can be used for fast and robust microstructure analysis on engineering surfaces. A fringe projection technique with an optimized grating pattern is used to determine the third dimension of the specimen. Due to the zoom objective the set- up can be quickly adapted to different fields of view. The magnification dependent vertical resolution can be as high as 0.1 micrometer with measuring times of less than a few seconds for 768 X 568 pixels. This very high speed together with the flexibility of the set-up is of great advantage for tribological investigations of metal sheets for example. After a brief description of the set-up and the algorithms used for the measurement evaluation, the mains emphasize is given for the application of the fringe projection technique to the determination of roughness parameters. Conditions like the optimal size of the field of view and others are given. In particular we give some studies for the comparability to a tactile sensor and to other optical sensors like white-light interferometry and confocal microscopy and present results of measurements on metal sheets and paper.
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.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
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.