Method and apparatus for the detection of aerobic microbes on non-living surfaces in which electromagnetic radiation having a wavelength greater than 350 nm is directed onto the surface to cause excitation of pyridine nucleotides present in microbial cells to emit radiation having a higher wavelength. That higher wavelength radiation and reflected radiation is then sensed as a measure of the amount of microbial cells on the surface.

A method for UV (ultraviolet) fluorescence counting of selected biological masses, such as egg masses, on foliage samples comprising the steps of: exposing a foliage sample having attached egg masses to UV radiation by a scanning beam; discriminating between the fluoresced light due to the masses and the fluoresced light due to other biological or foliage components; and counting the egg masses based upon the fluoresced light emitted by the egg masses. Also, an apparatus for UV fluorescence counting of egg masses on foliage samples is provided comprising a sample feed means having a test chamber; combined electro-optical sample scanner, fluorescent light divider, and detector; and an electronic signal discriminator and counter for selecting the divided fluorescent light signals emitted by egg masses from the emitted light of other foliage components, to thereby provide a count of the egg masses.

A device automatically reads indications of flaws in a piece using the swing method. An ultraviolet beam illuminates the piece to be checked after successive reflections on a separating mirror and on two oscillating mirrors for sweeping. The beam reemitted parallel to the incident beam traverses the separating mirror and is received by a detector, the output information of which is transmitted to a data processing unit which also receives information on the position of the oscillating mirror over a different path.

A method for laser induced fluorescence of tissue in which laser radiation is used to illuminate and induce fluorescence in the tissue under study to determine the chemical composition or pathologic condition of tissue. The laser radiation and the retrieved fluorescing radiation can be conveyed through a catheter using an array of optical fiber. The fluorescence spectrum of the tissue can be displayed and analyzed to obtain information regarding the chemical composition and medical condition of the tissue inside the human body.

A system for detecting the radiant energy emitted from different closely spaced species includes two detectors each having a large entrance angle for receiving the radiant energy, and wavelength selective filters between the detector and species, the transmission vs. wavelength characteristics being complementary, and means for ratioing functions of the detector outputs, the ratio being indicative of the identity of the species.