optics.gif (6954 bytes)

PROJECTION OF AN IMAGE WITH CONVERGING LENSES AND A CONVERGING MIRROR








EQUIPMENT
    redball.gif (326 bytes) Lenses
    redball.gif (326 bytes) Mirror
    redball.gif (326 bytes) 6 Volt Lamp
    redball.gif (326 bytes) Paper
    redball.gif (326 bytes) Object Box (if desired)
    redball.gif (326 bytes) 2 Optical Benches




NARRATIVE

            The purpose of this demonstration is to show the effects of a series of lenses.  Arrange the components as follows:

                                    redball.gif (326 bytes)  Adjust the 6 Volt lamp so that its beam is horizontal and falls of lens L1.

                        redball.gif (326 bytes)  The light converges to a point f1 at focal   length l1  from  L1 then diverges.

                        redball.gif (326 bytes)  Place the lens L2 so that its focal point coincides with f1. The light beam from L2 is now parallel.

                        redball.gif (326 bytes)  This beam is focused at a distance l3 by lens L3 and then diverges until being reflected by concave mirror M1.

                        redball.gif (326 bytes)  Move M1 until an image of the filament of the 6 Volt light source appears on the wall or screen.

            Blow smoke into the beam or burn touch paper to make the beam visible.