Optics Formulas

This course is designed to teach and reinforce the many optics formulas that ophthalmic techs may need to know for certification exams and clinical issues.

This course is intended for intermediate and advanced levels and offers numerous optics formulas with example problems and practice problems with an answer key. The optics formulas covered in this course are an absolute necessity for those taking the COT and COMT certification exams.

After completing this course the student will be able to:

• Identify Prentice’s Rule, know when to use it, know how to use it to solve problems dealing with induced prism and lens decentering
• Identify and understand Snell’s law regarding index of refraction
• Find out how much image displacement exists when looking through a prism of a certain amount
• List and define the different types of lenses: converging, diverging, spherical, astigmatic or cylindrical
• Describe the relationship between radius of curvature and lens steepness
• Calculate the focal point of a lens or calculate the power of a lens with a known focal point
• Calculate where an image will be formed given a known lens power and object distance from lens, or calculate the lens power given known image placement and object placement
• Calculate the sphere cylinder equivalent for prescriptions in plus cylinder and minus cylinder form
• Transpose prescriptions from plus cylinder to minus cylinder form and vice versa
• Understand and describe refractive states of myopia, hyperopia, emmetropia, and astigmatism
• Calculate the far point of accommodation for an eye
• Understand the types of astigmatism- simple myopic, compound myopic, simple hyperopic, compound hyperopic, mixed
• Draw optical crosses for both spherical and astigmatic prescriptions
• Use Prentice’s rule with optical crosses to find induced prism in astigmatic prescriptions
• Calculate amplitude of accommodation, near point, far point, or refractive error given the other 2 values
• Calculate total prism effect OU when given prism amounts for OD and OS- understand how prism in each eye affects total prism amounts

This course should take approximately 1 hour to complete.

This course has been approved by the AOA Commission on Paraoptometric Certification (CPC) for continuing education credit for use toward paraoptometric certification renewal.