Abstract: A nephelometer is disclosed which employs immersion optics and conformable optical couplers between components to minimize scattered background light. A multi-compartment micro volume specimen holder employs a cover having integral spacer knees which assure a precision length optical path. The device has the ability to collect small forward-angle scattered light with maximum efficiency and sensitivity. Light pipes are employed to remove a glass-air interface to a remote point where scattering is of much less importance and to act as an axicon for the compact collection of angularly scattered light.

Abstract: To reduce substantially the level of background light which will limit the sensitivity of any photometric measurements and to avoid using optical cements and greases and their inconveniences, optical components as employed in photometric measuring systems are coupled by an optically clear compliant member which is forced into conforming contact with two opposing optical elements. The invention finds application in photometers and densitometers, spectrophotometers, fluorometers and nephelometers. The invention may also be employed in lieu of the usual immersion oil of a high power microscope.

Abstract: A disposable low cost laboratory slide for measuring particle concentration has a base plate in the form of a standard microslide whose thickness is compatible with microscope optics. Tapes of precise thickness formed of chemically inactive material and possessing mechanical stability are adhesively bonded to the base plate in spaced relationship, the thickness of the tapes establishing a precision depth for a volumetric slide chamber. A thin coverslip of standard thickness overlies the tapes and is bonded thereto, the thickness of the coverslip also being compatible with microscope optics. The disposable slide is used in a simple optical system with magnification wherein the field of interest is focused on a precision graticle or screen enabling precise measurement of the area of the slide volumetric chamber, following which the precise volume of the chamber can be determined and the concentration of particles in a specimen within the chamber calculated with precision.

Abstract: A holder for a microscope slide and an indexing slide, such as a London Finder, aligns the two elements and mounts in the conventional microscope stage clamp.