This four-hour course will introduce lenses to those with little to no prior exposure. Throughout this course, there will be a maximum reliance on ideas and cartoon descriptions as to how things work, and an absolute minimum of use of mathematics. As a preliminary exercise, we will learn how prisms deviate an incident ray of light. Lenses will next be introduced by considering a lens as an assembly of three prisms, demonstrating thin lens laws, concepts of focal length, image position, the differentiation between real and virtual images, magnification, and optical gathering power. Chromatic aberrations will be addressed.

Attention will be paid to motivate an understanding of the eyepiece, the telescope, the microscope, and the spatial filter. The ability of delivering the power of a laser to a tiny spot will be reviewed, and we will see that an understanding can be developed without the confusing mathematics of Gaussian optics. Also, the concept of "wavefront" will be introduced to show a very different picture than the image transformation laws.

Each idea is explained in clear and simple terms with an emphasis on underlying physical principles and with a minimum of mathematics. Pertinent references and review material are identified. The course notes contain copies of each vuegraph used during the day so that participants can spend a maximum amount of time listening and understanding.

Benefits:
This 4-hour course will enable you to:

• Understand how lenses bring parallel rays to focus.
• Understand how lenses work when the inputted rays are not parallel.
• Appreciate the image-transformation properties of lenses.
• Understand chromatic aberration in lenses.
• Appreciate how lenses concentrate laser beams
• Appreciate the simplest instruments, the telescope, microscope, and eyepiece.
• Learn the useful concept of "wavefront" and its application to understanding lenses.

Continuing Education Units (CEU's) available upon request.