Portland Community College | Portland, Oregon

Upon successful completion students should be able to:

1. Use knowledge of optic principles to skillfully perform retinoscopy and lensometry.
2. Apply the decision process of optics to work in an optical setting.
3. Use detection principles of prisms to skillfully measure a patient’s pupillary distance.
 

The class will be presented by means of lecture/discussion, audio-visual presentations, handouts and demonstrations. There will be comprehensive lab work requiring demonstrated competency to receive a satisfactory grade. Guest speakers and field trips may be utilized by the instructor as a means of assisting the student in mastering course goals and objectives.

At the beginning of the course, the instructor will detail the methods used to evaluate student progress and the criteria for assigning a course grade. The methods may include one or more of the following tools: examinations, quizzes, homework assignments, research papers, laboratory modules, student participation and demonstration of competency.

Course Content

The student will demonstrate understanding of the following themes, issues, concepts, and development of the following skills:
THEMES, ISSUES, CONCEPTS

1. Retinoscopy
2. Radius of Curvature and Diopter Conversion
3. Near Addition-Bifocals, Trifocals, Progressives and Presbyopia
4. The Boxing System of Frame Measurements  
5. Ophthalmic Prism
6. Ophthalmic Dispensing

COMPETENCIES AND SKILLS

Radius of Curvature and Diopter Conversion

1. Define index of refraction
2. Define surface curvature
3. Describe how lens material indexes other than 1.530 will create an important difference in diopter curve or true power of the surface
4. Use a formula to convert diopters to radius of curvature in millimeters.
5. Use a formula to convert radius of curvature to diopters.
   
   The Near Addition-Bifocals, Trifocals, Progressives and Presbyopia

1.      Recognize presbyopia by inclusion of add power to an Rx or listening to client visual complaints.

2.      Algebraically, calculate a near or intermediate Rx from patient prescription.

3.      Using the lensometer, neutralize near or intermediate Rx.

4.      Define intermediate power as a percentage of near power.

5.      Write ANSI standards for addition power.

6.      Discuss importance of gathering information concerning a clients near and intermediate visual needs.
 

The Boxing System of Frame Measurements

1. Discuss frame markings for sizing.
2. Define the following terms and give synonyms for: "A", "B", "ED", "DBL", "FPD".
3. Explain how frame measurements are checked by the optician.
4. Define Major Reference Point (MRP)
5. Explain MRP and optical center (OC) differences.
6. Define lateral and vertical decentration of MRP in finishing of single vision lenses and multifocals.
7. Define total decentration.
8. Discuss ANSI standards for MRP, segment distances and heights.

Ophthalmic Dispensing

1. Describe the materials used to make ophthalmic frames; list the advantages/disadvantages of each.
2. Describe the process of frame selection; cosmetic considerations, interpretation of prescription, measurements necessary.
3. Explain the use of salt pans in dispensing; techniques for adjusting frames to avoid damage.
4. State the uses and techniques of the lens clock and vertometer.

5.      Explain the various tints and coatings common to ophthalmic lenses.