Shared Flashcard Set

Details

VOLUME 3
Optics
215
Medical
Professional
07/15/2012
Click here to study/print these flashcards.

Create your own flash cards! Sign up here.

Additional Medical Flashcards

 

 

Cards

Term
What definition of light states that it’s “that which we see by”?
 Definition
Clinical.
Term
What are the two basic theories of light propagation?
 Definition
Particle (corpuscular) theory and electromagnetic wave theory.
Term
Which theory is best used to explain the emission and absorption of light?
 Definition
Particle (corpuscular) theory.
Term
Who proposed the basic wave theory?
 Definition
Christian Huygens, a Dutch physicist and astronomer.
Term
According to the electromagnetic wave theory, what are the vibrating particles and the wave motion of light?
 Definition
Vibrating particles are actually mobile electrical charges and the wave motion is a magnetic radiation.
Term
Which theory helps explain the transmission of light through various transparent and translucent mediums?
 Definition
The electromagnetic wave theory.
Term
What is the visible portion of the electromagnetic spectrum?
 Definition
The wavelengths between 400and 750 nm.
Term
To what do the different wavelengths within the visible portion of the electromagnetic spectrum correspond?
 Definition
Different colors of light.
Term
Define emission.
 Definition
The sending out of light energy.
Term
What is it about the light that is emitted from a source that affects how things appear to us?
 Definition
The spectral qualities of the light.
Term
If an object is not actually emitting light, how can you see it?
 Definition
It reflects (emitted) light and our eyes see that reflected light from the object.
Term
Define absorbed light.
 Definition
That which is neither transmitted through nor reflected off of an optical system.
Term
What happens to absorbed light?
 Definition
It is converted to a different form of energy, usually heat.
Term
Give the name for the principle that states, “light travels in a straight line through a constant medium.”
 Definition
Rectilinear propagation of light.
Term
What are the top and bottom of a waveform called?
 Definition
The top is the crest or maxima; the bottom is the trough or minima.
Term
What color light is formed by a 400 nm long wavelength? How about one 750 nm long?
 Definition
16. 400 nm is violet; 750 nm is red.
Term
To what does amplitude correspond?
 Definition
Brightness of light.
Term
Frequency is dependent upon what two variables?
 Definition
Wavelength and velocity.
Term
What power does divergent light have?
 Definition
Negative power.
Term
What kind of power does parallel light have?
 Definition
Zero or plano power.
Term
How do light rays become convergent?
 Definition
They must pass through an optical system that bends the light rays toward each other.
Term
What is always found between the incident ray and the reflected ray?
 Definition
The normal.
Term
List the laws of reflection.
 Definition
(1) The angle of incidence equals the angle of reflection.
(2) The incident and reflected ray lie on opposite sides of the normal.
(3) The incident ray, the normal, and the reflected ray all lie along the same plane.
Term
What happens to parallel light that hits a convex mirror? A concave mirror?
 Definition
It gets diverged. It gets converged.
Term
What is the optical counterpart of an object?
 Definition
An image.
Term
How can you tell if an image is real or virtual?
 Definition
If you can hold a piece of paper in front of the light rays and see the image on the paper, it’s a real image. If not, it’s a virtual image.
Term
Imagine your image in a plane (flat) mirror. Is your image real or virtual? Are you erect or inverted? Are you normal or reversed?
 Definition
Your image is virtual, erect, and reversed.
Term
Define refraction.
 Definition
The bending of light rays as they travel from a medium of one density to another medium of a different density.
Term
List the four laws of refraction.
 Definition
(1) When light travels from a medium of lesser density (like air) to a medium of greater density (like a
lens), the path of the light is bent toward the normal.
(2) When light travels from a medium of greater density (like the inside of a lens) to a medium of lesser
density (like back out into the air again), the path of the light is bent away from the normal.
(3) The incident ray lies on the opposite side of the normal from the refracted ray.
(4) The incident ray, the normal, and the refracted ray all lie in the same plane.
Term
List the three factors that influence the amount of refraction that takes place when light goes from one medium to another.
 Definition
(1) Angle of incidence.
(2) Curvature of the new medium.
(3) Density of the new medium.
Term
What two effects does a prism have on light?
 Definition
Deviation and dispersion.
Term
When light enters a prism, which way is it deviated, or bent?
 Definition
Toward the base of the prism.
Term
Define dispersion.
 Definition
The breaking down of white light into its component colors (ROY G BIV).
Term
If a person looks at an object through a prism, where does the image of that object appear to move?
 Definition
Toward the apex of the prism.
Term
When a prism is used in glasses, what needs to be specified about the orientation of the prism?
 Definition
Where the base of the prism goes (e.g., base up [BU], base down [BD], base in [BI], or base out [BO]).
Term
How do you make a convergent lens using two prisms? A divergent lens?
 Definition
Convergent––put the prisms base to base. Divergent––put the prisms apex to apex.
Term
A lens has a +6.75 curve on its front surface and a –5.00 curve on its back surface. What would be the approximate overall lens power?
 Definition
+1.75.
Term
What kind of lens is thick in the middle?
 Definition
Plus lenses.
Term
What is the major factor that influences the power of a lens?
 Definition
Surface curvature.
Term
What does “r” stand for?
 Definition
Radius of curvature.
Term
Which lens would have a steeper curve, one with an “r” of 7 inches or one with an “r” of 14 inches?
 Definition
The lens with an “r” of 7 inches would have a steeper curve.
Term
What is index of refraction?
 Definition
The ratio between the speed of light in a vacuum and the speed of light in a given medium. Or more simply, a rating of an optical material’s density.
Term
All other factors being equal (i.e., lens thickness, surface curvature, and angle of incidence), which lens would refract light more, one with an “n” of 1.5 or one with an “n” of 1.9?
 Definition
The one with an “n” of 1.9.
Term
Explain Snell’s law.
 Definition
If the angle of incidence and the angle of refraction are known, the index of refraction of the material the
light passed through could be calculated.
Term
If light passes through a lens traveling from left to right is converged, what would the light do if it passed backwards through the lens going right to left? Why?
 Definition
It would still be converged. The Law of Reversibility has proven this happens.
Term
Give the simplified definition of polarization.
 Definition
The process of totally eliminating the light waves in one meridian and allowing all the light rays in the
meridian 90° away to pass through.
Term
What is the most common variety (shape) of ophthalmic lenses?
 Definition
Meniscus.
Term
List the three basic ophthalmic lens types.
 Definition
(1) Spheres.
(2) Cylinders.
(3) Spherocylinders.
Term
What type of lens has the same power in all meridians and has only one curve on the front surface and one curve on the back surface?
 Definition
Spherical.
Term
What type of focus does a spherical lens form?
 Definition
A point focus.
Term
A cylindrical lens has maximum power in one meridian. What kind of power does it have in the meridian 90° away?
 Definition
Zero (no power).
Term
What type of focus does a cylindrical lens form?
 Definition
A line focus.
Term
How much power does the axis meridian of a cylinder have?
 Definition
None.
Term
What are other names for a spherocylindrical lens?
 Definition
Toric or compound.
Term
How many curves does a toric lens surface have?
 Definition
Two.
Term
What kind of a focus does a spherocylindrical lens form?
 Definition
Two-line foci, 090°away from each other, and at different distances from each other.
Term
What unique figure, or characteristic, does a spherocylindrical lens form?
 Definition
Sturm’s Conoid (or Interval of Sturm).
Term
In the following spherocylindrical prescription, describe what the first, second, and last set of numbers represent: –1.00 –2.00 × 090.
 Definition
–1.00D sphere power, –2.00D cylinder power, with the axis meridian located at 090°.
Term
What kind of patient will a spherocylindrical lens help?
 Definition
One who is nearsighted or farsighted and has astigmatism.
Term
Which form of spectacles lenses has two or three primary foci?
 Definition
Multifocals.
Term
What is the only difference in prescription (power) between the distance portion of a multifocal
lens and the segment?
 Definition
The segment portion contains more positive (+) sphere power.
Term
What are the two ways of modifying a lens to get more sphere power in the multifocal segment?
 Definition
(1) Increase the index of refraction in the segment to get a fused multifocal.
(2) Increase the steepness of the lens curvature (i.e., decrease the radius of curvature) to get a one-piece
multifocal.
Term
List the five types of lens aberrations.
 Definition
(1) Chromatic.
(2) Spherical.
(3) Distortion.
(4) Oblique astigmatism.
(5) Curvature of field.
Term
If a person wearing spectacles complains distortion is causing the image of a square to appear as a
pincushion shape, what kind of lenses would you logically presume were in the glasses?
 Definition
Plus lenses.
Term
Which two aberrations can be corrected with a corrected curve lens?
 Definition
(1) Oblique astigmatism.
(2) Curvature of field.
Term
What is the thickness of a dress safety lens at its thinnest point?
 Definition
2.2 mm.
Term
What is the thickness of an industrial safety lens at its thinnest point?
 Definition
3.0 mm.
Term
How can glass lenses be made more impact resistant?
 Definition
By treating them chemically or with heat.
Term
What is the standard lens material used by optical fabrication labs?
 Definition
CR-39 plastic.
Term
What kind of impact resistant treatment is given to the CR-39 plastic lenses used by the military
optical labs?
 Definition
Nothing is done. CR-39 plastic is naturally impact resistant without treatment.
Term
What is one big reason the military labs switched from glass to plastic lenses?
 Definition
CR-39 is inexpensive and breaks less frequently during manufacture.
Term
What is the main disadvantage of plastic lenses compared to glass lenses?
 Definition
They scratch more easily.
Term
Who can get polycarbonate lenses?
 Definition
Pilots who must wear NVGs and monocular patients.
Term
In what cylinder form is single-vision and multifocal lenses ground?
 Definition
Minus cylinder form.
Term
A trifocal has how many primary foci?
 Definition
Three.
Term
For what viewing distance is the (middle) intermediate segment of a trifocal appropriate?
 Definition
30 inches.
Term
Into what two categories can bifocals and trifocals be divided?
 Definition
Fused and one-piece.
Term
How can you tell whether a multifocal has a fused segment or not?
 Definition
By feeling the top edge of the segment portion. If you do not feel a ledge, it’s fused. If you do feel a ledge,
it’s a one-piece.
Term
Which multifocals can look like single-vision lenses?
 Definition
PAL or no-line multifocals.
Term
What does the “28” stand for in ST-28?
 Definition
The width of the bifocal segment is 28 mm at its widest point.
Term
Can active duty military members get a Kryptok bifocal?
 Definition
No.
Term
What is the minimum “add” power that must be requested when ordering a bifocal?
 Definition
+0.75D.
Term
What is the most popular justification used to order the ST-35 bifocal?
 Definition
“Pt requires a wide FOV at near.”
Term
Can active duty military members get a double “D” bifocal?
 Definition
Yes, for specific occupational needs.
Term
What does the “8” stand for when a trifocal is described as being 8 × 35?
 Definition
The height of the intermediate segment (i.e., how tall it is).
Term
What is the minimum “add” power that must be requested to order a trifocal?
 Definition
+1.50D.
Term
What is a lens that requires a justification?
 Definition
A special-purpose lens.
Term
What method does the optical lab use to tint plastic lenses?
 Definition
A dye process.
Term
What colors are used most when tinting military spectacles lenses?
 Definition
Gray and pink.
Term
What is the military standard tint for sunglasses?
 Definition
N-15 and N-31, neutral density gray tint.
Term
How much light is reflected or absorbed by an N-15 tinted lens?
 Definition
85 percent.
Term
What justification is required to get tint in the AFF frame?
 Definition
There is no specific justification required. The verification the person receiving the glasses is on flying
status is justification enough.
Term
Rose tint is useful for which patients?
 Definition
Patients who have a sensitivity to fluorescent lighting or those getting eyestrain from a lot of computer work.
Term
When in doubt about which gradient of Rose tint to order for someone, what should you order?
 Definition
The Rose #1 tint.
Term
Who is authorized antireflective-coated lenses?
 Definition
Aircrew members that are on flight status.
Term
What color is the UV400 coating?
 Definition
Clear.
Term
UV400 coating is justified in cases of medical need. When else is it justified?
 Definition
When patients perform a lot of computer work.
Term
What justifications should not be used on spectacles orders for retirees?
 Definition
Those of an occupational nature.
Term
List the eight optical devices not available through military optical labs.
 Definition
(1) Photochromic lenses
(2) Polarizing lenses.
(3) Progressive add lenses.
(4) Shooting glasses.
(5) Hearing aid spectacles.
(6) Low vision aids.
(7) Lenses in 1/8 diopter power increments.
(8) Uncut lenses.
Term
List the three basic parts of a spectacles frame.
 Definition
Frame front and two temples.
Term
What does DBL stand for?
 Definition
Distance between lenses.
Term
What is frame PD (FPD)?
 Definition
The distance from the geometrical center of one lens to the geometrical center of the other lens when they
are mounted in a particular frame.
Term
What is the FPD for a 52-26-4½ frame?
 Definition
78 mm.
Term
What measurement is FPD and PPD used to determine?
 Definition
Decentration.
Term
What other term is used for skull temples? Comfort cables?
 Definition
Bent library. Riding bow.
Term
The length of which temple style is based on the distance from the butt to the bend?
 Definition
Skull (bent library).
Term
When fitting a pair of AFF frame, what is the effect on the fit if you spread the adjustable nose pads further apart?
 Definition
The glasses sit lower on the face.
Term
A patient is wearing a 50-22 male S-9 frame. The segment height of their multifocal is too low. Besides going to a frame with adjustable nose pads, how could you effectively raise the segments in relation to the patient’s eyes?
 Definition
By putting the lenses into a narrower bridged frame front; in this case, a 50-20 frame size.
Term
What size hinge is on the S-9 frame?
 Definition
7 barrel.
Term
What bridge sizes does the male S-9 come in?
 Definition
20, 22, 24, and 26 mm.
Term
On the S-9 frame, in what three lengths are CCs available?
 Definition
6 ¼", 6 ½", 6 ¾".
Term
When ordering the male S-9 frame with adjustable nose pads, what compensations to frame size and/or temple length should you make?
 Definition
Order the bridge one size larger and the temples ¼" longer.
Term
What bridge sizes are available for the female S-9 frame? Can the female S-9 be ordered with adjustable nose pads?
 Definition
18, 20, 22, 24 mm. No.
Term
What range of vision are half-eye spectacles meant to correct?
 Definition
Near vision only.
Term
What eyesizes does the half-eye come in? What bridge sizes?
 Definition
One size when ordering either black or amber colored frames: 46-24. If ordering gray fade or brown fade
colors there are two eyesizes available, 48, 50 and two bridge sizes available 20, 22.
Term
Give the restrictions imposed for ordering half-eyes.
 Definition
They are ordered only for patients who need correction of their near vision; military labs do not accept prescriptions for half-eyes that have minus sphere power and/or more than -1.50D of cylinder power.
Term
What are the two types of AFF frames available?
 Definition
AFF frame black and AFF gold.
Term
What are the three eyesizes available for the AFF frame?
 Definition
52, 55, or 58 mm.
Term
Who can get the gold AFF frame?
 Definition
Only Navy personnel and general officers (0-7 rank and up).
Term
Can the AFF frame be ordered with an NVO Rx?
 Definition
No.
Term
How many AFF frames are aircrew members who are on active flight status authorized?
 Definition
Two pairs with clear lenses and two pairs with tinted lenses.
Term
How many and what types of AFF frames are personnel on inactive flight status authorized?
 Definition
One pair of clear AFF frames per year.
Term
Does the need for a bifocal qualify or disqualify a person for a GMI?
 Definition
Qualifies the person.
Term
Give the two justifications that can be used when ordering GMIs.
 Definition
(1) POM (Preparation for Overseas Movement or Patient On Mobility) or (2) POR (Preparation for
Overseas Replacement).
Term
Into which gas masks does the M-17 GMI fit?
 Definition
M-17 and M-17A1.
Term
Into which gas masks does the M-17A1 GMI fit?
 Definition
M-17A1, M-9, M-24, and M-25.
Term
In which gas mask is the MAG-1 GMI used?
 Definition
MCU-2/P.
Term
What eyesizes, bridge sizes, and bridle sizes does the MAG-1 GMI come in?
 Definition
Eyesize: 46, 48, 50 mm. Bridge: 22 and 25 mm. Bridle: short or regular.
Term
What fitting changes should you make if the frame front of the MAG-1 GMI touches the faceplate of the mask?
 Definition
Go to a smaller eyesize.
Term
Which patients are authorized to order the nonstandard frames?
 Definition
AFOSI, intelligence personnel, and explosive ordnance personnel.
Term
Who is authorized the standard P-3 spectacles?
 Definition
Navy submarine personnel actively assigned as crew members.
Term
Which spectacles are active duty general officers authorized?
 Definition
Their choice of frames stocked by military multivision laboratories for issue to active duty military
personnel. This does not include nonstandard frames.
Term
When selecting the correct bridge size for frame fitting, you notice gaps between the bridge and the nose, also the frame is resting on the nose. What is the problem?
 Definition
This would indicate the bridge size selected is too wide.
Term
While checking the eyesize of an S-9 frame, you notice the temples seem to be flaring out away from the head. What does this indicate?
 Definition
The eyesize is too narrow.
Term
Describe a proper temple fit.
 Definition
You want the bend of the temple to be right at the top of the ear so the end of the temple curves downward
following the contours of the back of the ear (within 1/8 of an inch of touching the ear).
Term
A patient has a high dioptric power prescription. You’re not sure whether to go with the 48- or 50-mm eyesize, as they both seem to fit well. Which eyesize should you choose and why?
 Definition
48; it decreases noticeable aberrations, weighs less, and is easier to fit a frame that is too narrow than one that is too wide.
Term
What is the PD measurement?
 Definition
The distance from the center of one pupil to the center of the other pupil.
Term
Ideally, a person wearing prescription eyewear should be looking directly through what part of the lenses?
 Definition
The optical centers.
Term
What problems might the patient experience if the lab does not line the OCs up to match the patient’s PD?
 Definition
Eyestrain, headaches, and double vision (diplopia) from induced prismatic effect.
Term
If you ordered a 48-24 frame and the patient’s PD is 60 mm, how much decentration is required in each lens and in which direction?
 Definition
6 mm IN for each lens.
Term
What can happen if you poorly measure a patient’s PD and then order the glasses using the wrong PD measurement?
 Definition
The lab’s calculations and decentration will be wrong and the patient experiences unwanted prismatic
effect. This leads to eyestrain, headaches, and, potentially, even diplopia.
Term
When taking a patient’s PD, who should be sitting higher, you or the patient?
 Definition
Neither. You and the patient should be at eye level with each other.
Term
Theoretically, how close to the patient should you be when taking a PD?
 Definition
16 inches (40 cm).
Term
When you are lining up the zero mark of your PD ruler, at which one of your eyes should the patient be looking?
 Definition
Your left eye.
Term
When taking the near PD measurement (on an orthophoric or heterophoric patient), at which one of your eyes should the patient be looking? Which one of your eyes do you use to take the
measurement?
 Definition
Your left eye. You’ll also take the measurement with your left eye.
Term
When taking the distant PD measurement (on an orthophoric or heterophoric patient), at which one of your eyes should the patient be looking? Which one of your eyes do you use to take the
measurement?
 Definition
Your right eye. You’ll also take the measurement with your right eye.
Term
You found the patient’s near PD was 61 mm and his or her distant PD was 64 mm. How would you record the measurements?
 Definition
64 / 61.
Term
List the most common errors made when taking a PD.
 Definition
(1) Misreading the ruler.
(2) Moving the ruler after the initial alignment of the zero mark is made.
(3) Tilting the ruler so one side is closer to the patient’s face than the other.
(4) Not “cutting the eyes in half” properly, which leads to taking the measurement too low on the eyes.
(5) Trying to measure from the edge or center of the pupils instead of from the limbus.
Term
What does the patient need to do besides look into your left eye to line up the zero mark when taking a PD measurement on a strabismic patient?
 Definition
Close or cover, his or her left eye.
Term
To take the near PD measurement on a strabismic patient (after you have gotten the zero mark lined up correctly), what does the patient need to do besides look into your left eye?
 Definition
Open (or uncover) his or her left eye and close (or cover) his or her right eye.
Term
How do you calculate the distant PD for a strabismic patient?
 Definition
Add 3 mm to the patient’s near PD measurement.
Term
Why is the ability to determine a patient’s monocular PD considered one of the major advantages
of a pupillometer?
 Definition
Because monocular PDs are needed for ordering progressive bifocals.
Term
From which two points is a bifocal segment height measured?
 Definition
From the top edge of the lower eyewire to the lower limbus (or top edge of the lower lid if it is covering the
lower limbus).
Term
From which two points is a trifocal segment height measured?
 Definition
From the top edge of the lower eyewire to the bottom edge of the patient’s pupil.
Term
How many millimeters, if any, do you add to your segment height measurement to account for the
depth of the eyewire groove?
 Definition
1 mm.
Term
What should the room lighting be when measuring a trifocal segment height (i.e., bright, normal,
or dim)?
 Definition
Normal room lighting.
Term
How do you indicate to the optical fabrication lab that you measured for the entire trifocal
segment height?
 Definition
By putting the word TOTAL after the measurement.
Term
Assuming you’ve checked the frame is level, what should you do if the segment heights you
measured for each lens differ by 1 mm or less? What if the measurements differ by 2 mm or
more?
 Definition
Order each lens with the same segment height, using the smaller of the two measurements. If the difference is 2 mm or more, order each lens with the segment height measured in that eye.
Term
Who calculates decentration?
 Definition
The optical fabrication lab.
Term
It is 01 Oct 2007. You walk into the clinic, and the first patient of the day is a retiree who wants
to order spectacles with a current prescription. What order number do you record on this patient’s
DD Form 771?
 Definition
1–08.
Term
When ordering spectacles for a retiree, what must you record in the ADDRESS/UNIT block of
DD Form 771?
 Definition
The retiree’s home address.
Term
What do you record in the EYE size of DD Form 771 when you order standard AFF frame
spectacles?
 Definition
The eye size desired.
Term
You want to order MAG–1 GMIs. What do you record in the TEMPLE length and style section
of DD Form 771?
 Definition
Put the bridle size, either “SMALL” or “REG.”
Term
What do you record in the INTERPUPILLARY DIS block of the DD Form 771 if you are
ordering half-eye spectacles?
 Definition
Put the “Near” PD and dash the “Dist” PD section or put both PDs down, but circle the “Near” PD.
Term
How many pairs of spectacles can you order for a retiree?
 Definition
One.
Term
What do you record on the DD Form 771 right after the SEGMENT HEIGHT measurement of a
trifocal prescription?
 Definition
The word “Total.”
Term
What goes in the SPECIAL COMMENTS/ JUSTIFICATION section of the DD Form 771?
 Definition
Any additional information required to clarify the spectacles prescription and/or for justifications.
Term
What is the prescription order logbook?
 Definition
A consolidated record of orders sent from the clinic to the optical fabrication lab.
Term
What is a mandatory requirement for the entry in the prescription order logbook when you are
ordering AFF frame?
 Definition
The patient’s signature certifying that he or she is eligible for AFF frames, in accordance with Air Force
directives.
Term
Which copies of the DD Form 771 are sent to the optical fabrication lab?
 Definition
Copies #1 and #2.
Term
Which copy of the DD Form 771 is wrapped around the spectacles when they come back from
the optical fabrication lab?
 Definition
Copy #2.
Term
What should you do when spectacles arrive at your clinic from the optical fabrication lab?
 Definition
Pull your file copy of the DD Form 771 (copy #3); annotate the prescription order logbook with the date the
spectacles arrived; verify the spectacles against the DD Form 771 showing what was ordered; notify the
patient to pick up the spectacles (if they are okay) or notify the patient of the delay to the order (if the
spectacles did not check out correctly).
Term
A pair of spectacles arrived from the optical fabrication lab and is ready for pick up. You have
tried everything and still cannot get in touch with the patient. What can you do with the
spectacles?
 Definition
Disassemble them and use them for parts or send them back to the optical fabrication lab.
Term
What do you do with the second and third copies of the DD Form 771 when the patient picks up
the spectacles?
 Definition
Copy #2 goes in the patient’s medical record and copy #3 goes to the patient.
Term
At least how much time must pass before you can send a tracer to the optical fabrication lab for
an order that has not come in?
 Definition
At least 45 days.
Term
For what is SRTS designed?
 Definition
To allow the optometry clinic to collect prescription information and electronically transmit the prescriptions to their supporting optical fabrication lab (OFL). It also allows the clinic to track and reorder
prescriptions, generate specific reports, and eliminate the need for handwritten logbooks.
Term
Into what two sections is the Rx ordering screen divided?
 Definition
The upper section is for patient information. The lower section is for the spectacles information.
Term
What does a red asterisk indicate?
 Definition
Any block with a red asterisk is mandatory.
Term
When using SRTS how can you get a complete listing (drop down list) of choices?
 Definition
For a complete listing of choices available, hit your enter key twice. A drop down menu appears.
Term
In the SRTS Rx ordering screen, what does “T” mean?
 Definition
It indicates the order is ready to transmit.
Term
What instruments are designed specifically to determine the power of a lens?
 Definition
Lensometer, vertometer, lensmeter.
Term
What is the primary use of a projection lensometer?
 Definition
Teaching.
Term
How is the eyepiece of a lensometer focused?
 Definition
With power set at zero, turn the eyepiece as far as possible CCW and then slowly rotate it CW until the
reticle comes into sharp focus.
Term
How is calibration of the lensometer checked?
 Definition
Looking into the lensometer, turn the power wheel until the sphere and cylinder power lines are clear and
sharp. Look at the power wheel, it should read zero, exactly. If it does not, recheck. If it still does not read
zero, the lensometer needs calibration.
Term
What does it mean if the sphere and cylinder lines do not focus at the same time?
 Definition
The lens has some cylinder power.
Term
How is the cylinder power calculated?
 Definition
By determining the distance traveled between the points where the sphere power lines are in focus to the
point where the cylinder power lines are in focus.
Term
What two methods are used to measure the “Add” power in multifocals?
 Definition
Practical and exact.
Term
When using a manual lensometer, what is used to accurately measure a progressive addition lens?
 Definition
Templates of the lens manufacturer.
Term
What is the only authorized maintenance you can perform on the lensometer?
 Definition
Placing dust covers, dusting exterior lenses, and changing the light bulb.
Term
When changing light bulbs on lensometers, how does the procedure differ between the B&L
vertometer, and the AO lensometer?
 Definition
B&L vertometer power wheel is turned in the minus direction to –20.00D and the AO lensometer power wheel is turned in the plus direction to +20.00D.
Term
When using the automate lensometer, what happens if both lenses are not against the table?
 Definition
The axis reading will be inaccurate.
Term
For what is the PD the most accurate method?
 Definition
Measuring a lens, checking for prism, or verifying the Rx from the lab.
Term
What is the name of the standard that governs tolerances for spectacles fabrication?
 Definition
ANSI Z80.1.
Term
Are the standards for ophthalmic lenses enforceable by law?
 Definition
No.
Term
What type of physical marring to a spectacles lens is acceptable?
 Definition
Hairline scratches that are essentially invisible to the eye without intense scrutiny.
Term
When measuring the base curve of a lens, you find the front surface of the lens has a meridian of
maximum curvature and 90° away it has a meridian of minimum curvature. Which reading is the
base curve?
 Definition
The weaker curve (minimum curve).
Term
What dioptric tolerance for sphere and cylinder powers is always considered within standards?
 Definition
A sphere or cylinder power that is only off by 0.12D.
Term
What is the given tolerance for horizontal prism according to the ANSI standards?
 Definition
0.67Δ.
Term
What are the two acceptable ways of checking or calculating horizontal prism?
 Definition
A lensometer or the Prentice Rule.
Term
Name the five items on the verification checklist you need to reference when verifying a pair of
spectacles.
 Definition
(a) Ensure frame size, style, and temples are accurate.
(b) Examine lenses for defects.
(c) Measure the segment heights.
(d) Neutralize Rx: sphere, cylinder, axis, (and “Add” if spectacles are multifocal).
(e) Check for prism tolerances: vertical and horizontal.
Term
Name the three tools used to tighten loose rivets in the frame front and temples of the S–9 and half-eye frames.
 Definition
The hinge and staking tool, the rivet burnishing pliers, and the automatic punch.
Term
What is the number one injury to technicians in the eye clinic?
 Definition
Stabbing themselves with optician’s screwdriver.
Term
When you install a new temple, what other new item should you use?
 Definition
A new screw.
Term
Which side of the lens should you insert into a frame front first?
 Definition
Temporal side first; nasal side last.
Term
In what direction do you rotate a lens to increase the axis?
 Definition
Rotate the lens CCW.
Term
What specific parts of the frame to you adjust to get the frames in a “neutral and straight” starting
position?
 Definition
The nose pads (if adjustable), the frame front, and the temples.
Term
What two things are accomplished by moving spectacles around in a salt or glass-bead frame warmer?
 Definition
(1) Even heat distribution to the frame.
(2) Prevention of “pitting” or “stippling” of the plastic by the salt or glass beads.
Term
Which file would you use on the AFF frame to file off excess material on the butt of a temple?
On the S–9 frame?
 Definition
A fine-toothed metal file. A coarse-toothed file.
Term
How would you position the Zyl gripping pliers so you would not mar the temple?
 Definition
You would have the metal part of the tool on the inside of the temple and the padded portion would be on the outside of the temple.
Term
When adjusting frames for a patient, how should the nose pads be fit?
 Definition
They should have even, complete contact with the nose.
Term
After adjusting the frames to a patient’s face, what should you look at to ensure the frames are level?
 Definition
Look at the locations of the patient’s eyes in the frames.
Term
Which items are included in a final inspection checklist for frame fitting?
 Definition
(a) Adjust nose pads to fit evenly, without digging in. Check nose pad alignment by viewing from the front,
the side, and above.
(b) Frame front is level in relation to the patient’s eyes, when viewed from the front.
(c) When viewed from above the frame front is an equal distance from each eye, .
(d) Temples correctly contoured, when viewed from the side and the rear.
Term
How do you adjust the temples on the AFF frame to fit the MBU 13/PCB mask?
 Definition
Cut the temples to a length of 15–20 mm and file the cut ends smooth.
Term
Name the two methods used to solve problems regarding the AFF frame and oxygen mask.
 Definition
Cut the nose pads off a pair of AFF frames and file the area smooth. Order a 50–26 S-9 frame with a stretching and reshaping the bridge.
Term
Describe the procedures for adjusting the AFF frame when an aircrew member has problems with the frames and full-pressure-suit helmet.
 Definition
At approximately ½ inch from the butt of each temple, make a bend inward at an angle of about a 45°. At approximately ½ inch from the first bend, make a bend outward at an angle of about a 45°.
Supporting users have an ad free experience!