A portable reflectometer is made using a diffuse light and light sensor cination to measure reflectivity of solar wavelengths. A cadmium sulfide photocell is used as the light sensor connected to a voltage divider network which provides a linear response to an internal light source. The light shield is placed around the light source and the light sensor to limit detected light to only that reflected on the surface due to the diffuse light source. The invention is mounted in a hand-held gun confi...

A reflection meter for measuring the percentage of reflected light from a surface. A light source produces light which strikes the surface. The surface reflects the light into a chamber which directs the light to a detector. The detector senses the reflected light and produces a detect signal that represents the light reflected. A microprocessor receives the detect signal and calculates a percentage of light reflected from the surface which is shown on a display. An absorbing receiver engage the...

The present invention comprises reflectometer for detecting and measuring subtle changes in color and shade of color. In general, a pulsating light source illuminates a target surface which possesses a certain color and shade of color. An optical detection circuit synchronously detects light that is reflected from the target surface and generates an output signal whose voltage is indicative of the color and shade of the target surface. This voltage is then processed to make an evaluation and ide...

A reflectometer, comprising an illuminator in a 45.degree./0.degree. configuration with a light source formed by a lamp and an illuminator optic. Light emitted by the lamp is passed after reflection via a measuring opening into a housing and supplied to a measuring system contained therein. Furthermore, the illuminator optic is formed by a number of light guides which start at the light source and end in the form of a rim with a conoidal emission side. The light guides form one or several groups...

A modulated light source emits light to illuminate a target surface which possesses a certain color and shade of color. Light that is reflected from the target surface is detected by an optical detector. The output from the optical detector is processed and fed back to the optical detector to compensate for any shift caused by ambient light, temperature or other external factors, and is differentially amplified to generate an output signal indicative of the color and shade of the target surface....

A device for testing the quality of interior walls of tubes, utilizing reflected light inside the tube. The quantity of reflected light in a given section of the tube is measured by means of a photocell and displayed externally of the tubing. The device is movable within the tubing so that all sections of the tubing can be tested.

A reflection-type graduation having a silicon substrate. The silicon substrate has first subsections formed thereon. Each of the first subsections has etched oblique surfaces. The surfaces are positioned so that light beams directed incident to the surfaces cause no retroreflection. The substrate also includes second subsections having relatively higher reflecting properties as compared to the first subsections. The first subsections and second subsections are alternatively disposed on the subst...

An apparatus and method to measure the absolute reflectivity of a sample is made by use of a multiple pass reflectometer. A given light beam permits measurement of the absolute reflectivity by comparing a portion of the light beam in a reference White cell to the change in light of another portion of the beam which undergoes equivalent reflections except for the addition of the sample in one configuration as compared to the other.

An instrument is provided, primarily as a refractometer, and which has the unique capability of distinguishing and identifying finished gems and gem materials by their refractive index and/or ratio of reflected light to projected light, and for exposing spurious imitations. For gem stone analyzing purposes the instrument is based on the Fresnel formula, which requires a flat highly polished surface, the formula reading n = (r - 1).sup.2 /(r + 1).sup.2 Where n is the ratio of reflected light to p...

A thin, compact reflectometer is adapted to support and position a generally planar test element in a predetermined, generally horizontal plane during usage. The reflectometer includes a light source and a detector having major portions of their respective illumination and detection axes extending generally parallel to a planar reflectometer-positioning portion on one of two major surfaces of the reflectometer.