Abstract: A laser photometer including means forming an unsupported curtain of liquid sample, means for focusing a laser beam at a sample volume in the unsupported liquid curtain, means for receiving a cone of light issuing from the sample in an incremental angle .DELTA..theta. at an angle .theta., means for focusing the cone of light at a field stop and a detector for receiving the power passing through the aperture.BACKGROUND OF THE INVENTION1. Field of the InventionThis invention relates to laser light scattering photometers used to measure the size of particles dispersed in liquids and, more particularly, to a particle handling technique wherein the particles are contained in a thin flat unsupported curtain of the liquid which contains the scattering volume.2. Description of the Prior ArtWhen a beam of radiant energy (light) is incident upon a particle, a portion of this energy will be scattered.

Abstract: An optical cavity for a flash lamp pumped dye laser including a pumping cavity, a birefringent filter and a plurality of frequency doubling crystals. Within the pumping cavity the flash lamp is cooled by forced air convection and operated with a D.C. simmer current. Simultaneously, the dye carrying conduit within the pumping cavity is cooled with water. The operating life of the dye is increased by using selectable filters to remove the ultraviolet radiation eminating from the flash lamp before it falls on the dye. The construction of the pumping cavity permits changing the flash lamp and the dye conduit without disturbing the optical path of the laser.