Abstract: The invention is an apparatus for determining the quality of optical equipment through measurement of the modulation transfer function of the equipment. The apparatus includes an elongated, opaque sheet member or reticle, uniformly curved about an axis substantially perpendicular to the longitudinal centerline thereof, which has a data pattern comprising at least one bar pattern of discrete spatial frequency positioned longitudinally thereon. Each of the data patterns has optical transmission characteristics that vary periodically along its length according to a predetermined spatial frequency distribution. A rotatable mirror with its axis of rotation coincident with the center of curvature of the reticle is mounted so that it reflects an incident image onto the stationary reticle.

Abstract: An instrument and method for applying high pressures of short duration, with very little temperature rise in the sample, to disrupt tissue, kill cells, etc., is described. The instrument uses an accelerating piston to apply a strong impact upon a sample contained in a chamber capable of holding the very high pressures produced. Following the chamber is a nozzle section. The nozzle has a receiving end cap with an impact surface and a receiver extension which can vary the distance between the nozzle exit and the impact surface. Depending upon the acceleration of the piston and sample size, a portion of the sample emerges from the nozzle as a hypervelocity jet while the remainder stays in the nozzle. The part of the sample remaining in the nozzle will have been subjected to the pressures built up by the shock wave created when the piston strikes the sample seal.