Portable luminescence sensor
AssigneeAtlantic Richfield Company
InventorRobert D. Watson
Life of this patent
Estimating the term…
Abstract
Apparatus is provided to sense and measure solarinduced luminescence, as well as reflectance, within the field of view of a target window for receiving a composite ray of light from the target. A first filter within the path of the composite ray of light transmits a first narrowband component thereof, including a predetermined Fraunhofer Line frequency, to a first sensor. A second narrowband component thereof, proximate the Fraunhofer Line frequency, is directed to a second sensor such that ratios of the electromagnetic energy impinging, respectively, on the first and second sensors may be determined. A removable filter tray assembly carrying the narrowband filters and fine tuning means are employed to facilitate the selection of the predetermined Fraunhofer Line frequency.
Claims15
An apparatus for receiving a composite ray of light from a target, which composite ray of light includes reflected light having at least one Fraunhofer Line and may include solar induced luminescent radiation and for sensing and measuring the relative value of the luminescent radiation if present, said apparatus comprising:
- a. a body;
- b. a target window carried by said body for receiving said composite ray of light therethrough along a first optical path;
- c. a first optical filter aligned along said first optical path for:
- i. transmitting therethrough a first fraction of said composite ray of light along said first optical path, said first fraction of said composite ray of light being limited to a first selected waveband containing a selected Fraunhofer Line, and
- ii. redirecting the remainder of said composite ray of light along a second optical path;
- d. a second optical filter aligned along said first optical path for limiting the light energy content of light passing therethrough to a second selected waveband which is narrower than said first selected waveband and including, but wider than, said selected Fraunhofer Line;
- e. tuning means for effecting selective angular adjustment of said second optical filter relative said first optical path;
- f. first sensor means aligned along said first optical path for receiving light in said second selected waveband and for sensing the electro-magnetic energy level contained therein;
- g. a third optical filter aligned along said second optical path for transmitting a narrowed waveband in the continuum offset from said selected Fraunhofer Line by a selected frequency difference;
- h. second sensor means aligned along said second optical path for receiving said light in said narrowed waveband in the continuum and for sensing the electromagnetic energy level contained therein;
- and
- i. indicator means for providing a sensible readout of the energy level sensed by said first and said second sensor means.
An apparatus particularly adapted as a portable, handheld instrument for receiving a composite ray of light from a target for sensing and measuring the relative value of luminescent radiation present in said composite ray of light and which composite ray of light includes reflected light having at least one Fraunhofer Line, said apparatus comprising:
- a body including means forming a target window for receiving said composite ray of light therethrough along a first straight line optical path;
- a first optical filter aligned along said first optical path for transmitting therethrough a first fraction of said composite ray of light along said first optical path and of a first selected waveband containing a selected Fraunhofer Line, and redirecting the remainder of said composite ray of light along a second optical path extending at an angle to said first optical path;
- a second optical filter aligned along said first optical path for limiting the light energy content of light passing therethrough to a second selected waveband including, but wider than, said selected Fraunhofer Line;
- first sensor means aligned along said first optical path for receiving light in said second selected wave band and for sensing the electro-magnetic energy level contained therein;
- a third optical filter aligned along said second optical path for transmitting a narrowed waveband in the continuum offset from said selected Fraunhofer Line by a selected frequency difference;
- second sensor means aligned along said second optical path for receiving said light in said narrowed waveband for sensing the electro-magnetic energy level contained therein;
- and
- viewing scope means carried by said body having an ocular lens disposed along a third optical path for receiving at least a portion of said composite ray of light which is redirected by said first optical filter and said third optical filter for directly viewing an image through said target window.
Dependencies are inferred from the claim text.