Printing block illustrating system involves optical element of variably spaced planes and wedge elements to vary focus and definition by beam test

摘要

Downstream optical element (E) has two flat faces (S1,S2) at continuously variable spacing (deff) to pass the light emitted from source (1). The bases of two wedge-shaped components of the element (E) are opposed to form an angle with their hypotenuse and the refracting planes to give the parallel faces (S1,S2). The two wedge shapes can mutually adjust along the base line. To change the distance of the image point from the light source (1), the effective spacing (deff) of the two faces (S1,S2) has to be modified, preferably by means of actuator (75).