Ultrasensitive spectrophotometer
US6741348B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 2002 |
| Grant date | May 25, 2004 |
| Priority date | — |
| Expiry date | Apr 29, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01J3/42
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention concerns improvements in spectrophotometry. Aspects of the invention may be used independently or together to increase the sensitivity of spectrophotometry. One aspect of the invention is a spectrophotometer detection circuit. In this aspect of the invention, currents attributable to reference and sample beams are cancelled in the current mode. The detection circuit produces a first voltage proportional to the difference in currents and a second voltage proportional to one of the reference or sample beams. Both voltages are available to allow simultaneous measurement and analysis. Another aspect of the invention concerns thermal stability. According to the invention, thermal conductivity is established among the housing and optical system components to promote equilibrium. Another preferred embodiment has a unitary solid metal housing with a hollowed portion defined to mount and place optical system components. Recognition and identification of important noise sources in spectrophotometers forms an aspect of the invention contributing to the features and combinations of features in preferred embodiments. Many noise sources would not normally be considered in conventio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.