CH 6 Neutralization and Verification
Cards (36)
- What is the description of a gradient tint?
- When focusing the eyepiece of a lensometer, why is it important to stop turning the eyepiece when a sharp focus is first obtained?
- When measuring a lens in minus cylinder, if the cylinder lines focus at a more plus reading than the sphere lines, you should rotate the axis wheel by __________ degrees.
- An important factor in measuring lenses with an automated lensometer is keeping the lens __________ against the lens stop.
- When tapping a glass lens with your fingernail. the sound will be _______________ than the _______________ sound of a plastic lens.
- True or false? A polycarbonate lens should be treated with a UV coating to avoid damage to the eye from UV radiation.
- On orders that include prism, both the amount of prism and the prism __________ direction should be specified.
- What instrument is used to measure the power of spectacle lenses?
- Which part of the lens measuring device indicates that the instrument has power?
- What is the first procedure in lensometry?
- When measuring a lens, if both sets of lines making up the target sharply focus at the same time, the lens is a _______________ power lens.
- How is the power wheel scale graduated for power between -3.00 and +3.00?
- When measuring a lens, you find that the target sphere lines focus at -2.25 D with the cylinder axis wheel at 93 degrees, and the cylinder lines focus at -4.75 D without changing the cylinder axis. What would be the presentation of the lens?
- The amount of prism in a lens is measured using the lensometer _______________.
- In the boxing system, the ________________ dimension is the largest vertical dimension measured between the two horizontal tangents to the bevel tips.
- A __________ is used to measure the surface powers base curve of a lens.
- A colmascope is used to verify that a glass lens has been _______________.
- When verifying lens optical quality, the primary defect to search for is a localized area of _______________.
- What is the cylinder axis tolerance for a lens with a cylinder power of -1.00 D?
- There can be no more than _______________ prism diopters of unwanted horizontal prism in a lens.
- There can be no more than _______________ prism diopter of unwanted vertical prism in a lens.
- The vertical segment location tolerance for a mounted lens is within ______ mm of specification.
- For special purpose prescription lenses, the thickness tolerance is ______ mm.
- If a base curve is specified when a lens is ordered, it should be supplied within ______ D.
- If the distance PD is 64 and the near is 60, what is the seg insert?
- When the lensometer was calibrated, the target focused sharply at +0.25 and was blurred at zero. You are neutralizing a lens and have a reading of +1.00 on the lensometer. How would you record this reading?
- If both sets of lines making up the target sharply focus at the same time, the lens being neutralized is a
- If the two sets of lines in the projected target will not come into focus at the same time, the lens being neutralized is a
- The cylinder lines will focus at a more ________________ power reading than the sphere lines when neutralizing a lens in minus cylinder
- What must be accounted for when measuring prism?
- Which glasses measurement is the same as the DBL?
- What glasses measurement is the largest horizontal measurement?
- What is the separation of the two lenses in a frame at the nasal bevel tips referred to as?
- Which glasses measurement is the largest vertical measurement?
- The lens bevel used most commonly for low power lenses edged to fit into plastic and metal frames is called a?
- What does the fitting cross represent in the marking of a progressive lens?