Readhead with reduced height sensitivity
US4659229A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 10, 1984 |
| Grant date | Apr 21, 1987 |
| Priority date | — |
| Expiry date | Oct 10, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/065
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A readhead with reduced height sensitivity for use in a reflectance photometer that measures reflectance of diffuse light from a sample disposed outside the readhead includes a housing with an upper spherical portion and a lower conical portion. The inner peripheral surface of the upper portion is hemispherically configured and the inner peripheral surface of the lower portion is conically configured to permit illumination of a sample disposed outside the readhead. The angle of the cone defined in the conical portion of the housing is in the range of 45.degree.-60.degree.. The inner peripheral surfaces of the upper and lower portions are coated with a highly reflective material, such as barium sulfate. The apex of the conically configured housing portion is truncated to provide a light transmitting aperture for sample illumination. A sample is positioned adjacent the light-transmitting aperture below and outside the conically shaped readhead housing portion. The housing includes a second aperture for receiving a high intensity light from a flash lamp or incandescent light to illuminate the interior of the housing and diffusely illuminate the sample. A baffle is located adjacent the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.