Data processing: measuring – calibrating – or testing – Measurement system – Dimensional determination
Patent
1998-07-27
2000-04-25
Shah, Kamini
Data processing: measuring, calibrating, or testing
Measurement system
Dimensional determination
702159, 356 501, 342 95, G01S 1386
Patent
active
060554908
ABSTRACT:
An apparatus and method for measuring coefficients of retroreflectance of retroreflective surfaces such as road signs involves use of a modified light based range finder. The apparatus includes a power attenuation factor data base which relates pulse width of received pulses to power attenuation of the transmitted pulses. The range finder calculates target range based on time of flight of light pulses. The apparatus automatically calculates the absolute coefficient of retroreflectance for an unknown reflective surface being measured by comparison of the measurement to a reading with the same instrument of a known reflectance standard. The method involves either recalling a stored standard reference reflectance factor or determining a reflectance factor via the range finder for a sample of retroreflective material with a predetermined coefficient of retroreflectance, and then measuring the distance to an unknown target, determining a power attenuation factor from the received pulse width from the unknown target and then calculating the absolute coefficient of retroreflectance based upon these determined values of power attenuation factor, distance and the reference reflectance factor.
REFERENCES:
patent: 5291262 (1994-03-01), Dunne
patent: 5359404 (1994-10-01), Dunne
patent: 5521696 (1996-05-01), Dunne
patent: 5781147 (1998-07-01), Elliott et al.
ASTM Designation E 810--94 Standard Test Method for Coefficient of Retroreflection of Retroreflective Sheeting.
Kubida William J.
Laser Technology, Inc.
Shah Kamini
Wahl John R.
LandOfFree
Apparatus and method for determining precision reflectivity of h does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for determining precision reflectivity of h, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for determining precision reflectivity of h will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1001633