Exam (elaborations)
Precise practice-PO Questions With Complete Solutions
- Course
- Institution
Precise practice-PO Questions With Complete Solutions
[Show more]
Content preview
Precise practice-PO Questions With Complete SolutionsA -4.00 D spectacle lens is decentered 5 mm temporally over the
patient's right pupil. Which of the following prisms is induced?
2 PD BI
2 PD BO
20 PD BO
20 PD BI Correct Answer 2 PD BI
A bitoric GP contact lens with BCR 42.00/45.00 D and powers -
1.00/-4.00 D is fit on the patient's left eye. The over-refraction is
+0.75 DS. Assuming a good lens-to-cornea fitting relationship,
what bitoric GP contact lens powers should be ordered?
-1.00/-3.25 D
-1.75/-4.75 D
-0.25/-4.00 D
-0.25/-3.25 D Correct Answer -0.25/-3.25 D
simply add the OR to the CLP
A CR-39 spectacle lens has a +8.00 D front surface power and a
-10.00 D back surface power. If this lens has a center thickness
of 3 mm and is worn at a vertex distance of 12 mm, the shape
magnification produced by the lens is approximately:
1.00
0.98
1.02
1.04 Correct Answer Ms=1/(1-(t/n)Fsp)
1/ (1- ((.003/1.498)(8))
,1.02
A CR-39 spectacle lens has a back vertex power of +4.00 D. If
this lens has a center thickness of 3 mm and is worn at a vertex
distance of 10 mm, the power magnification produced by the
lens is approximately: Correct Answer 1.05
Use the power magnification formula where 1 / (1 - hFv) where
h is the distance between the lens and the entrance pupil of the
eye expressed in meters (vertex distance + 3 mm (distance
between the cornea and the entrance pupil of the eye) and Fv is
the back vertex lens power. The answer of 1.05 means there is
5% magnification due to this lens.
A horizontal prism is ground on a 50 mm lens blank with n =
1.50. The nasal edge thickness is 2 mm and the temporal edge
thickness is 6 mm. What is the prism's power?
4.00 PD
2.00 PD
8.00 PD
6.00 PD Correct Answer 100* g(n-1)/l
100* ((6-2)(1.50-1))/50)
4.00 PD
A lab is fabricating a +5.00 DS Rx in a high-tech "wrap around"
frame. The facial wrap of the frame is 26°. What would you
expect the resultant Rx to be due to the wrap, assuming the
optical center location of each lens has NOT been compensated
for?
,Decrease in plus sphere power with minus cylinder induced
Decrease in plus sphere power with plus cylinder induced
Increase in plus sphere power with plus cylinder induced
Increase in plus sphere power with minus cylinder induced
Correct Answer increase in plus sphere power with plus
cylinder induced
Increasing frame facial wrap will induce the following lens
power changes:
1. The sphere power will increase, keeping the same sign as the
original sphere power.
2. The cylinder power will increase, keeping the same sign as
the original sphere power.
3. The axis of the induced cylinder power will be 090 degrees.
A lensometer has a standard lens of +22.00 D. The target moves
20.7 mm toward the standard lens from the zero position. Which
of the following is the power of the lens?
-10 D
+20 D
-20 D
+10 D Correct Answer +10 D
A myopic spectacle lens Rx increases in power from -2.00 DS to
-7.00 DS. Based on corrected curve design, how should the base
curve be changed in the higher Rx in order to maintain good
optics?
Steepen
Flatten
Stay the same Correct Answer Flatten
, A patient complains about seeing "rainbows of light" when he
looks through the periphery of his spectacle lenses. Which of the
following materials would MINIMIZE this complaint?
Polycarbonate
CR-39
High index glass 1.80
High index plastic 1.60 Correct Answer CR-39
A patient complains that she has to lower her chin using her
PAL spectacles in order to see clearly to drive. Assume the
spectacle Rx is correct. Which of the following frame
adjustments would BEST address her complaint? SELECT 2
Decrease distance between nose pads
Increase face form
Increase pantoscopic tilt
Decrease face form
Decrease pantoscopic tilt
Increase distance between nose pads Correct Answer Increase
pantoscopic tilt
Increase distance between nose pads
A patient complains that she has to raise her chin in order to
read clearly through her PAL add. Which of the following frame
adjustments would BEST address her complaint? SELECT 2
Decrease pantoscopic tilt
Increase face form
Increase distance between nose pads
Decrease face form
Decrease distance between nose pads
Increase pantoscopic tilt Correct Answer Decrease pantoscopic
tilt
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Classroom. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $17.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
75759 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy study notes for 14 years now