A sixteen minute videotape of an optical lab was made. This tape was prepared to be used in classes of ophthalmic optics to explain to optometry students how a pair of glasses is made. An account of each step involved in the process is contained on the videotape

Hallstrom, Sheldon L

English

CommonKnowledge

Pacific University 
CommonKnowledge 
College of Optometry Theses, Dissertations and Capstone Projects 
3-1983 
A videotape of an optical lab, "Just what the doctor ordered: The 
optical lab in perspective" 
Sheldon L. Hallstrom 
Pacific University 
Recommended Citation 
Hallstrom, Sheldon L., "A videotape of an optical lab, "Just what the doctor ordered: The optical lab in 
perspective"" (1983). College of Optometry. 655. 
https://commons.pacificu.edu/opt/655 
This Thesis is brought to you for free and open access by the Theses, Dissertations and Capstone Projects at 
CommonKnowledge. It has been accepted for inclusion in College of Optometry by an authorized administrator of 
CommonKnowledge. For more information, please contact CommonKnowledge@pacificu.edu. 
A videotape of an optical lab, "Just what the doctor ordered: The optical lab in 
perspective" 
Abstract 
A sixteen minute videotape of an optical lab was made. This tape was prepared to be used in classes of 
ophthalmic optics to explain to optometry students how a pair of glasses is made. An account of each 
step involved in the process is contained on the videotape. 
Degree Type 
Thesis 
Degree Name 
Master of Science in Vision Science 
Committee Chair 
James E. Peterson 
Subject Categories 
Optometry 
This thesis is available at CommonKnowledge: https://commons.pacificu.edu/opt/655 
Copyright and terms of use 
If you have downloaded this document directly from the web or from CommonKnowledge, see 
the “Rights” section on the previous page for the terms of use. 
If you have received this document through an interlibrary loan/document delivery service, the 
following terms of use apply: 
Copyright in this work is held by the author(s). You may download or print any portion of this 
document for personal use only, or for any use that is allowed by fair use (Title 17, §107 U.S.C.). 
Except for personal or fair use, you or your borrowing library may not reproduce, remix, 
republish, post, transmit, or distribute this document, or any portion thereof, without the 
permission of the copyright owner. [Note: If this document is licensed under a Creative 
Commons license (see “Rights” on the previous page) which allows broader usage rights, your 
use is governed by the terms of that license.] 
Inquiries regarding further use of these materials should be addressed to: CommonKnowledge 
Rights, Pacific University Library, 2043 College Way, Forest Grove, OR 97116, (503) 352-7209. 
Email inquiries may be directed to:.copyright@pacificu.edu 
A VIDEOTAPE OF AN OPTICAL LAB 
JUST WHAT THE DOCTOR ORDERED 
THE OPTICAL LAB IN PERSPECTIVE 
A VIDEOTAPE OF AN OPTICAL LAB 
JUST WHAT THE DOCTOR ORDERED 
THE OPTICAL LAB IN PERSPECTIVE 
A Thesis 
Presented to the 
Faculty of the College of Optometry 
Pacific University 
by 
Sheldon L. Hallstrom 
In Partial Fulfillment of the 
Requirements for the Degree 
Doctor of Optometry 
March 1983 
James E. Peterson 
PACIFIC UNIVERSITY 
(I(~OREST GROVE OBEG()N 
Acknowledgements 
I wish to thank all those at Opti-Craft who patiently cooperated 
with me throughout this project. Thanks also to Pacific University 
for the use of their video equipment. A special thanks to Dr. Douglas 
Stine, who was the initial advisor, and to Dr. James Peterson who 
supported and guided me through the majority of the project. I extend 
my appreciation to Dr. Willard Bleything for his assistance and for 
the original concept of making this videotape. Further thanks to 
Ed Collier for his expertise in narrating. A very special thanks to 
Gerard Gibbons for the countless hours involved in taping and editing. 
Abstract 
A sixteen minute videotape of an optical lab was made. This tape 
was prepared to be used in classes of ophthalmic optics to explain 
to optometry students how a pair of glasses ~s made. An account of 
each step involved in the process is contained on the videotape. 
-iii-
Time 
0:00 
0:11 
0:17 
0:26 
0:34-
0:48 
1:03 
1:12 
1:33 
1:43 
Narration 
Have you ever wondered what happens in an 
optical lab? We know how to write a pre-
scriptio~ but do we know what is involved 
in making a pair of glasses? 
I would like to welcome you to Opti-Craft, 
where more than 1700 pairs of glasses are 
made every day. 
In such a modern optical lab great care 
1s taken to fill the prescription just 
as the doctor ordered for there are many 
critical steps along the way. 
Let's enter the world of Opti-Craft and 
see what really takes place behind the 
scenes. 
Most prescriptions are called in by 
phone and recorded on the lab forms. 
Great care is taken to obtain all the 
necessary information from the doctor 
such as frame color, seg height, and 
the patient's P.D. 
The information for each job is placed in 
one of the many trays at the lab. These 
trays are color-coded to distinguish 
between jobs using glass lens blanks and 
those using plastic blanks. 
A unique conveyor belt system is utilized 
to transport the trays to each station 
throughout the lab. 
The information is then entered into the 
computer. The computer not only determines 
the doctor's bill, but takes the doctor's 
prescription, along with the characteris-
tics of the frame and the patient's P.D. 
and computes all the necessary numbers to 
be used throughout the lab in manufacturing 
the glasses. 
The computer printout is placed in the 
tray and is referred to often by the 
individuals in the lab. The process is 
just beginning. 
In this room the computer sheet is used 
in locating the exact frame the doctor 
ordered. The eye size, bridge size and 
temple length are also found on the com-
puter printout. 
-1-
Video 
car 
sign 
foyer 
doorway 
starting room 
trays 
conveyor belt 
computer 
printout 
stock room 
Time 
1:55 
2:10 
2:26 
3:05 
3:19 
3:33 
Narration 
The frame fronts are usually stored sepa-
rately from the temples. It is necessary 
for the lab to have a large inventory of 
frames so as not to delay the job by having 
to order the frame directly from the 
manufacturer. 
Next, lens blanks are obtained for the job. 
These lens blanks already have a finished 
spherical front curve and bifocal. The 
appropriate toric back curve will be ground 
on the back of the blank here at the opti-
cal lab. 
We now enter a large room where the real 
work begins. The conveyor belt will lead 
us to stations that will prepare the 
blank to be surfaced on the back. Other 
stations will finish this surface to a 
fine optical quality. A lens pattern will 
be chosen to act as a template to cut down 
the lens blank to the exact size and shape 
of the frame. The lens will be tinted 
and then inserted into the frame. As will 
be seen, each station is critical. 
Employees know that if thay fail to cor-
rectly perform their work the entire job 
must be done over. 
In order to generate a toric back curve 
in the correct orientation, a layout and 
blocking process must be carried out. 
First, a special protractor is used to 
mark the geometrical center and minus 
cylinder ax~s on the lens blank. 
The lens is then sprayed with a coating 
so a metal block can adhere to the front 
surface of the blank along the minus 
cylinder axis. The metal block has to 
be positioned like this to allow the 
generating machine to hold the lens blank 
in the correct orientation. 
It's actually three pinholes ~n the 
blocking body that are lined up on the 
correct axis. Pressure is then applied 
to the back surface of the lens blank 
and the metal block adheres to the 
front. 
2 
Video 
frame fronts 
lens blanks 
large room 
layout area 
spray 
blocking machine 
Time 
3:54 
4:15 
4:28 
4:55 
5:08 
5:33 
5:40 
Narration 
This special machine does the layout and 
blocking all at once. The left side has 
the protractor where the layout is done. 
The rotating arm has the lens blank. The 
metal block is then applied to the right 
side, whereupon it is bonded to the 
blank. 
This is the generator where the toric 
back curve is surfaced. The generator 
has three dials: one for regulating 
the base curve, one for regulating the 
cross curve, and one for the thickness. 
The blocking body, with the lens blank, 
is attached to the generator. The 
block is aligned correctly during this 
layout procedure so when it's attached 
to the generator the correct orientation 
corresponds with the three dial settings. 
The machine has a diamond-studded cutting 
wheel that cuts the toric back curve all 
at once. 
Even though the back curve is cut it is 
still very rough. A fining and polish-
ing process must take place to get rid 
of the generator lines making this sur-
face optically clear. 
Fining uses orange aluminum oxide pads 
which are placed on a metal lap. The 
correct lap is specified on the computer 
printout. The back surface of the lens 
blank will move across the lap and a 
very fine grating process will smooth the 
rough lens surface. Fining is a process 
which takes approximately 2~ minutes to 
complete. 
It's done with these special machines. 
The laps are placed directly on the 
machine. The blanks are then placed on 
the upper arms of the unit, concave 
side down. They are brought to rest 
against the lap and the machine is 
turned on. When fining is completed the 
blanks are removed from the machine, 
blown dry and inspected. 
3 
Video 
special machine 
generator 
close-up on 
blank 
other 
generators 
orange pads 
fining machines 
fining 
Time 
5:58 
6:15 
6:48 
6:56 
7:05 
7:25 
7:43 
Narration 
The blanks then move on to the polishing 
department. The 5~ minute process is 
very similar to fining. Magnifying 
lenses are used to check the polished 
optical surface. 
It's time for the blocks to be removed 
from the blanks. The blanks, with the 
metal blocks attached, are put in a spe-
cial tray and placed in a bath of hot 
water and soap. The blocks fall off the 
blanks and drop to the bottom of the 
tray. Any adhesive substance remaining 
on the lens blanks is cleaned off with 
the brush. The blanks are then tho-
roughly rinsed and placed ~ack into the 
plastic trays. 
Great care must be taken to make sure 
the lens blanks get back into their 
respective trays so the orders will 
not become confused. 
The trays are then taken over to the 
inspectors. 
The prescription is then checked at the 
next station along with the center 
thickness. The 180th degree axis is 
dotted with the lensometer. This axis 
will be referred to later during the 
layout process for pattern blocking. 
The inspector sets the axis first and 
then the power. 
The lens blanks are now optically clear 
and ready to be cut and edged to the 
correct size to fit their respective 
frames. Before the blanks can be cut 
and edged, the appropriate lens pattern 
must be selected. Once again the com-
puter printout is utilized to obtain the 
pattern number. 
These numbers allow the patterns to be 
readily located among the many thousands 
on hand. 
Video 
magnifying 
lenses 
deblocking 
4 
blanks back 
in trays 
inspectors 
lensometer 
pattern area 
pattern numbers 
Time 
7:50 
8:13 
8:46 
8:56 
9:25 
9:40 
Narration 
Opti-Craft provides a unique service to 
its doctors. Many times the doctor calls 
and needs to know where his prescription 
is and how much longer it will take to 
process. Well, here at Opti-Craft, the 
computer is updated at this station to 
tell how much of the job is completed 
and how much longer it is expected to take 
until the prescription is filled. 
The lens blanks can not just be cut to fit 
the frame. They must also be decentered 
to place the optical center directly in 
front of the patient's pupil. If this 
does not take place, resultant prismatic 
effects can occur. This decentration is 
accomplished by placing a metal pattern 
block in the correct location on the front 
of the lens blank before cutting and edging. 
The blank size is double-checked and the 
marked location is sprayed with an adhesive 
much like the procedure done in the first 
blocking operation. 
This is another machine that does the 
same, though somewhat more rapidly. 
The job moves on to the last stages of 
its travels through the lab. It has 
passed many stations so far and great 
care must still be taken so the lenses 
are not damaged during processing. 
What follows is pattern blocking, cutting 
and edging, and deblocking, followed by 
tinting, drop-ball testing and lens 
insertion. 
Here the pattern block is attached to 
the front surface of the blank. The 
plus mark on the blank is lined up with 
the center of the pattern block. Pres-
sure is applied at this location and the 
block is firmly adhered to the blank. 
The blank is now ready to be cut and edgerl. 
It is attached to the edger while the 
pattern is placed on the left side. The 
pattern looks like the eye rim shape of 
the frame but is usually smaller. An 
adjustment 1s made to compensate for the 
difference in size. This pattern acts as 
a template which the edger follows in 
5 
Video 
blue box 
pattern 
marking area 
faster 
machine 
conveyor belt 
blocking 
edger 
Time 
10:15 
10:37 
10:50 
11:05 
11:39 
12:06 
Narration 
cutting the blank. By making the proper 
adjustments on the edger, blanks can be cut 
for different eye sizes using only one 
pattern. This particular edger cuts the 
bevel automatically. 
The operator monitors the progress of 
many of these machines at the same time. 
The shield is lifted so he can directly 
observe the blank being cut down to the 
right size. 
The pattern blocks are now removed from 
the lenses. The lenses, with the pattern 
block attached are put in a tray which 
is then placed in a special bath. Each 
tray is checked periodically to see if 
the blocks have fallen off. 
In order for the lens to fit properly ~n 
the frame, special hand edging and 
beveling is done. The lens is custom 
fit for the frame so it will not chip 
or fall out. A considerable amount of 
care is taken during hand edging and 
beveling. 
A continuous pressure and motion ~s 
applied to the lens at all times. The 
lens is kept at the proper angle to the 
wheel so the bevel will be uniform 
around the circumference of the lens. 
This procedure must be done with care 
but quickly enough so as not to hold up 
production. 
We are now in the area where tinting is 
done. Many doctors will order tints 
on their plastic lenses. Some of the 
tinting is done by hand, as in this case. 
The lens is dipped in the hot dye which 
is absorbed by the lens material. The 
amount of time the lens is left in will 
determine the darkness of the tint. 
Before the tinting is done the lenses 
are cleaned of all remaining residue. 
6 
Video 
operator 
deblocking 
hand edging 
large wheel 
tinting area 
cleaning 
Time 
12:17 
12:37 
12:43 
12:51 
13:18 
13:47 
14:03 
Narration 
Sometimes the tinting is carried out by 
another method. In this method, an 
extended metal arm overhangs the dye. 
When the lens is attached, it will bob 
up and down in the dye to achieve the 
gradient effect seen on many of today's 
lenses. 
The tinted lenses are put back onto the 
trays and move on to where they will be 
drop-ball tested. 
According to federal safety standards, 
the lenses are tested using a 5/Sth 
inch ball dropped from a height of 50 
inches. 
Once again the lenses are inspected and 
cleaned. It's essential to check for 
any hairline fractures or chips. Any 
damage done by drop-ball testing would 
require the lens to be manufactured 
again. Once the lens has been tinted 
and tested, it is inserted into the 
frame. 
The frame used for this job is metal. 
Many metal frames require that extra 
care be taken with the lenses before 
they are inserted. Since metal frames 
are not as malleable as zyl frames, 
fine adjustments must be made to the 
bevel so that it will line up with the 
eyewire. Also, unlike a zyl frame, a 
metal frame does not stretch and could 
easily crack a slightly oversized lens. 
At this point, the job moves on to 
another area where fine adjustments 
and checks are made. Several measure-
ments are taken and compared with the 
data on the computer sheet. This helps 
to insure that the job turns out to be 
just what the doctor ordered. 
The glasses often require more minor 
adjustments. Sometimes, for instance, 
the lens is rotated slightly to line 
up the bifocal seg and any frame mis-
alignments are corrected. Of course, 
many other types of adjustments are also 
made to insure that the glasses will be 
acceptable to both the doctor and his 
patient. 
' J 
7 
Video 
extended arm 
lenses 1n 
trays 
drop ball 
testing 
cleaning 
metal frame 
measurements 
m1nor 
adjustments 
Time 
14:28 
14:50 
15:02 
15:10 
15:36 
15:40 
Narration 
The glasses are now placed back into the 
tray and move on to another station 
where they are cleaned and dried. 
Forced air is used to remove moisture on 
the lenses and is much faster and safer 
than using a towel. 
Now, it is time to verify the prescrip-
tion. Special care is taken to insure 
that the power and axis are within 
tolerances. Also, the P.D. and seg 
heights are checked. 
Once again the glasses are cleaned 
before they are finally ready to be 
mailed to the doctor. 
Only the final packaging remains to be 
completed. The art of making a pair 
of glasses is a detailed process that 
usually takes only a few days. A 
modern and efficient lab, with quality 
control in mind, ~s essential. Each 
step is critical and great care is 
taken to ensure that the glasses are 
just what the doctor ordered. 
no narration 
8 
Video 
cleaning 
verification 
cleaning 
packaging 
dispensing room 
credits 


A videotape of an optical lab,  Just what the doctor ordered: The optical lab in perspective

https://commons.pacificu.edu/cgi/viewcontent.cgi?article=1970&amp;context=opt

A videotape of an optical lab, Just what the doctor ordered: The optical lab in perspective

Abstract

Similar works

Full text

Available Versions

CommonKnowledge