Non-contact tonometer having non-linear pressure ramp
US6159148A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 13, 1998 |
| Grant date | Dec 12, 2000 |
| Priority date | — |
| Expiry date | Jul 13, 2018 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B3/165
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A non-contact tonometer having a fluid pulse generating system for causing corneal applanation is improved by changing the pressure versus time characteristics of the fluid pulse from a linearly increasing relationship of the prior art to a non-linearly increasing relationship which reduces the impulse energy delivered to the eye during testing for purposes of patient comfort. In a preferred embodiment, an automatically driven piston for producing an air pulse is provided with a linearly increasing current source for driving the piston mechanism, whereby the pressure ramp of the air pulse increases as a squared function of time to reduce impulse energy delivered to the eye.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.