NICMOS cold-well displacement monitor: A portable Hubble simulator

John E. Mentzell, Malcolm B. McIntosh, John P. Schwenker, Rodger I. Thompson

Research output: Contribution to journalConference articlepeer-review


The anomalous motion of the near IR camera and multi-object spectrometer (NICMOS) detector arrays was originally discovered and characterized during ground optical testing, in a large, high fidelity Hubble Space Telescope (HST) simulator. To monitor the state of the cryo-mechanical system, as NICMOS traveled among several testing sties, a portable stimulus was needed. The cold-well displacement monitor (CDM) was quickly assembled from a very simple design. The 'cheaper, better, faster' approach proved to be a winner here. Off-the-shelf optics, a simplified interface to the instrument, and a limited set of requirements were used. After calibration against the large refractive aberration simulator/Hubble opto-mechanical simulator (RAS/HOMS), the CDM gave results of similar accuracy to RAS/HOMS. It became the primary tool for the difficult job of managing the NICMOS cryogen system up through launch.

Original languageEnglish (US)
Pages (from-to)1044-1052
Number of pages9
JournalProceedings of SPIE - The International Society for Optical Engineering
StatePublished - 1998
EventInfrared Astronomical Instrumentation - Kona, HI, United States
Duration: Mar 23 1998Mar 23 1998


  • Hubble Space Telescope
  • Infrared camera
  • Instrument testing

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'NICMOS cold-well displacement monitor: A portable Hubble simulator'. Together they form a unique fingerprint.

Cite this