Our Laboratories, Workshop and Facilities

Our assembly hall is the main laboratory where instruments are being built. It consists of a pre-assembly environment used for unpacking, a main hall where instruments stand and a room used for consumable storage and small integration work.
Our laboratory is equipped with a rotating crane able to handle up to 5 ton instruments. Unfortunately its space has been until now too small and up to 3 instruments were integrated in parallel on a surface foreseen for only one. The situation will change in the future with the new ESO building where a new integration hall is foreseen.
The hall is also equipped with 2 Cassegrain simulators, a NTT Nasmyth flange simulator and a cryogenic facility for subsystem testing at liquid nytrogen temperature.
Our workshop is equipped with milling machines, CNC machine, drilling machines, cutting tools etc. However most of the instrument mechanical parts are manufactured by external companies because the workshop is too small to afford it and is not adapted for large pieces. It is actually intended to make modifications or urgent parts that cannot wait outsourcing. Nevertheless one staff member (Jean-Paul Kirchbauer) works full time in the workshop and helps at the high quality level of ESO instruments.
We offer also to other ESO laboratories full supplies of consumables like screws, o-rings, pipes, fittings which are maintained on a regular basis.
The metrology laboratory is dedicated to opto-mechanical measurements and dimensioning as well as small integration work. It is equipped with a 3D measuring machine, a shadow profiler and other precise measuring tools. The laboratory is under the responsibility of Christophe Dupuy.

Below is a list of the main measuring equipment under our responsibility which fills the full range of our integration activities.

Device
Use
Technical Description
Clinotronic Inclinometer Position angle measurement This device is an inclinometer able to measure the angle of a mechanical surface down to 10" accuracy on a limited range.More information here.
ELCOMAT VARIO 200 autocollimator Position angle measurement This autocollimator is used to make position angle measurement of translation (pitch, yaw, roll) or rotation device (wobble). It is also sometimes used to make flexure measurements. More information here.
Twyman-Green Versatile interferometer (TGV) Optical system quality control The TGV is a phase shift Twyman-Green interferometer developed internally for our optical testing duties. It works with green and red lasers and different objective sizes. It is equipped with a multi axes mount and can adapt for many kind of set-ups and interfaces. As a software the Intelli wave offers a very powerful interface with many acquisition and analysis features implemented.
HASO Hartmann wavefront sensor Optical system quality control This Hartmann wavefront sensor maps in real time the local slopes of the analyzed wavefront with the help of micro-lenses arrays, covering the visible bandwidth. It has a 64x64 lenslet array, can operate at 20Hz with a precision down to lbd/100 in absolute mode. This device is sold by Imagine Optics.
Sighting telescopes Optical system alignment Sighting telescopes are used for optical system alignment. We own several which are commercial or custom made ones. It can sight from zero to infinity, have an illuminated reticule for autocollimation. It is equipped with an analog camera and different magnifying objectives. Its adjustable mount can adapt for many king of set up, environment and interfaces.
Autocollimator-500 Moeller-Wedel Optical system alignment, function testing This autocollimator is used in general when angular measurements or sighting to infinite are needed. It has a 500mm focal length and is equipped with a useful light illumination and reticule wheel. Its adjustable mount can adapt for many king of set-up, environment and interfaces.
Tesa micro-positionner Function testing, alignment Tesa micro-positionner is an inductive sensor which allows accurate measurement of surfaces on a range of 1-2mm with a sub micrometer resolution. It mainly dedicated to function testings when reproducibility measurements are needed.
Shadow profiler - Mitutoyo Position measurement, assembly Our shadow meter is a profiler which allows measuring part dimensions like for instance masks or optics using their projected shadow with micrometric accuracy.
3D measuring machine Position measurement, alignment, large part dimension measurements Our 3D measuring machine is made of a movable arm which can measure dimensions of large parts and structures (typical 1m) with a 10 micrometer accuracy. It is equipped with a palper but can also adapt to a microscope. We use it for many integration purposes when dimensioning is required.
ELCOMAT autocollimator Function testing L'ELCOMAT is an electronic autocollimator which is capable of measuring the 0.1 arcsecond accuracy. We use it mainly for function testing or when stability measurement have to be done at cold temperatures (in combination with the cryogenic facilities).
Cassegrain Simulator large Instrument Flexure tests Our Cassegrain simulator facitility is a large structure simulating the Cassegrain adaptor rotator. It is adapted for the weight and interface of instruments which are installed on the Paranal UTs. It has an altitude axis which in combination with the adaptor rotator can give the instrument all operational orientations. This is important for instruments requiring high levels of flexure stability like for instance spectrographs.
Cassegrain Simulator small Subsystem flexure tests This simulator has the same purpose as above nevertheless it cannot be adapted to Paranal UTs. We use it for flexure testing of small instruments or subsystems.
Cyrogenic test facility Optical and function testing at cold temperatures
Build out of the vacuum vessel from IRSPEC (old near-IR spectrograph), this is a test bench for various components like pump, closed cycle cooler, pre-cooling system.
The facility is fitted with two windows allowing accurate position measurements with outside measuring tools (autocollimator, microscope, interferometer).
Alcatel Cryo-Sniffer Leak tests for cryo-vacuum devices Helium leak detector system sold by Alcatel. This is our main tool for leak detection of our cameras and instruments.
CCD camera - SBIG-ST7 Point spread function measurement, function testing The SBIG-ST7 camera is a CCD camera 765x510 pixels we use for PSF measurement. Its low read out noise and dark current are adapted to our psf measurements. We use it also for function testing when spot motion must be determine accurately at focal plane level. It has a pixel size of 9 microns and a USB link port.
FARO arm 3d measuring arm The FARO arm The FARO is a 3d measuring arm able which we use to check that structures or mechanical parts are manufactured within specification. It is a very useful portable unit connected via USB to a laptop. It can measure on a diameter of approximately 2m with an accuracy of the order of few 1/100 mm.
Nasmyth adaptor simulator telescope simulator This structure is use to simulate the Nasmyth adaptor flange of the VLT. Instruments are attached on it during their integration and testing phases. As on the telescope it can rotate by 360 degree (usually for flexure testing).