[nfb-talk] Optacon:

[Kenneth Chrane]

Hi Helene, this is Kenneth Chrane and Carol Siegel.
Didn't I correspond with you at one time?
Some one sent the Email about the Optacon to Carol but didn't send the 
person's contact information.
Sincerely,

Kenneth Chrane
and
Carol Siegel
----- Original Message ----- 
From: "helene ryles" <dreamavdb at googlemail.com>
To: "NFB Talk Mailing List" <nfb-talk at nfbnet.org>
Sent: Tuesday, March 03, 2009 4:06 PM
Subject: Re: [nfb-talk] Optacon:


>I hope the opticon does go back into ciculation. I learnt how to use
> an opticon and I do miss the fact that it is no longer in production.
>
> Helene.
>
> On 03/03/2009, Kenneth Chrane <kenneth.chrane at verizon.net> wrote:
>> This is something we might do well to support.
>> Jim Bliss
>> New Optacon Design Ideas
>>
>> *by James C. Bliss*
>>
>> *1/26/09*
>>
>> * *
>>
>>             The Optacon was designed in the late sixties at the dawn of
>> integrated circuits, silicon photocell arrays, and before 
>> microprocessors.
>> The
>> design was based on extensive experiments with human subjects, blind and
>> sighted, that used computer simulation of various designs to determine 
>> the
>> most effective for reading text.
>>
>> The final design incorporated a novel array of tactile stimulators 
>> composed
>> of piezoelectric reeds, or bimorphs, a custom integrated array of silicon
>> photocells, and custom integrated circuits of shift register/bimorph
>> drivers.
>>
>>             The custom integrated circuits and unique piezoelectric 
>> reeds,
>> together with the small market, made the Optacon a difficult product to
>> source parts and manufacture.  However, for those that mastered its use, 
>> the
>> Optacon filled an essential need.  Even though the Optacon has been out 
>> of
>> production for over fifteen years, there are still over 150 avid users
>> trying to maintain their Optacons and demanding a new Optacon.
>>
>>             Now, almost 40 years after the original Optacon design, 
>> advances
>> in technology make possible a new Optacon design that could have greater
>> resolution, be easier to learn and use, and could have features that 
>> would
>> greatly extend the applications of use.
>>
>>             To reach the widest possible market, it is important to keep 
>> the
>> simplicity of the original Optacon while enabling new capabilities and
>> applications.  Below are my thoughts on design possibilities that could 
>> be
>> considered.  Not all of these ideas may be worth developing, but 
>> considering
>> them to assign priorities could help the process toward a new Optacon.
>>
>> I.  Resolution and Field of View
>>
>>             The original Optacon was designed around an array of 24 rows 
>> and
>> 6 columns of pixels that drove a corresponding array of 24 rows and 6
>> columns of bimorph tactile stimulators.   The 24 by 6 was based on tests
>> with human subjects that indicated this was the minimum number of pixels 
>> for
>> reading and tracking text at a practical speed.  Actually, if you 
>> consider
>> 24 pixels across a 0.1 inch letterspace, this is equivalent to only 240
>> dots/inch compared to the 300 dots/inch typically considered to be the
>> minimum needed for OCR.  Also, the Optacon's 24 pixels across a 0.1 inch
>> letterspace is equivalent to a visual resolution of only 20/40.
>>
>>             In addition, reading with an Optacon requires the user to 
>> move
>> the hand held camera along a line of text.  The limited field of view of 
>> the
>> Optacon camera requires this scan to be very precise; else the images of 
>> the
>> text are cut off.  So reading would be easier and faster if the field of
>> view of a new design could be greater, thereby relaxing the precision 
>> needed
>> for line tracking.
>>
>>             Thus, for ease of tracking and reading a wider range of text
>> fonts and text quality, more pixels would certainly be better, analogous 
>> to
>> the greatly enhanced picture quality resulting from the recent television
>> change from a 480 line interlaced scan to a 1080 progressive line scan.
>>
>>             Fortunately, advances in technology make an improved 
>> resolution
>> and field of view possible at a reasonable cost.  Therefore, I believe 
>> that
>> a goal of basing a new design on 36 vertical pixels to provide both 
>> improved
>> resolution and greater field of view should be considered.
>>
>>             Unfortunately, the Optacon II, which was designed by Canon, 
>> had
>> only a 20 by 5 array.  This reduction in resolution and field of view was
>> one of the reasons reading is more difficult with it.
>>
>>             In the original Optacon design, the pixels were not square, 
>> but
>> rectangles that were twice as wide as they were high.  This is because 
>> when
>> camera is moved along a horizontal line of text the letterspace is 
>> sampled
>> in the vertical direction, but an analog signal is obtained horizontally
>> across the letterspace.  All of the image information can be obtained 
>> from
>> one column of pixels moved horizontally across the letterspace.  However,
>> tests with human subjects clearly showed that reading accuracy increased 
>> as
>> more columns were added.
>>
>>             Based on these considerations, I suggest that a new design 
>> have
>> 12 columns across the same horizontal field of view as the original 
>> Optacon.
>> Thus, the newly designed Optacon's pixels would be square, with the 
>> vertical
>> and horizontal resolutions being the same.  The 36 by 12 array would
>> increase the number of pixels to 432, compared to the 144 in the original
>> Optacon, perhaps justifying a name for the new model as "Optacon HD" for
>> "high definition".
>>
>> II.  Tactile Array
>>
>>             In the past 40 years, there have been some significant 
>> advances
>> in piezoelectric materials.  Several years
>>
>> ago there was a study at Stanford University that indicated the bimorph
>> reeds in the Optacon tactile array could be half as long as in the 
>> original
>> design.  This would allow incorporating the increased number of bimorphs 
>> in
>> approximately the same space as before.
>>
>>             A complaint about the Optacon has been the noise that it 
>> makes.
>> This noise comes from the bimorphs, which are being driven by a 250Hz 
>> square
>> wave, a frequency of maximum tactile sensitivity.  This provides a strong
>> tactile sensation.  The bimorph reeds were designed to be at near 
>> resonance
>> at this frequency to consume a minimum amount of power from the battery.
>> After
>> the Optacon design was finalized and production had begun, we discovered
>> this noise was greatly reduced if the bimorphs are driven with a 250Hz 
>> sine
>> wave instead of a square wave.  This is because the human ear is much 
>> more
>> sensitive to the harmonics of a square wave than to the fundamental 250 
>> Hz
>> frequency.  However, we never had the opportunity to test whether there 
>> was
>> any detrimental effect on the tactile sensation when a sine wave drive is
>> used instead of a square wave.  In a new design this should be tested and
>> the sine wave used if desirable.
>>
>>             At Telesensory the assembly of the tactile array was labor
>> intensive requiring considerable skill.  Modern manufacturing techniques
>> including robotics could help reduce this cost.
>>
>> III.  Retina Module
>>
>>             When the Optacon was designed, no suitable integrated solid
>> state arrays of photocells were available, so a custom design was 
>> developed
>> in the Stanford Laboratories. Finding and maintaining sources for this
>> custom part at the relatively low quantities needed made Optacon 
>> production
>> difficult and expensive.  Now integrated solid state arrays of photocells
>> are widely used in digital cameras, web cams, cell phones, etc.  Thus in 
>> a
>> new design, a standard off-the-shelf part should be used if at all 
>> possible.
>>
>> IV.  Lens Modules
>>
>>             The original Optacon lens is not a true zoom lens because 
>> only
>> the lens is moved to change the magnification.  This meant that the image 
>> is
>> only in true focus at two points along the zoom range and out of focus at
>> the ends and middle of the zoom range.  The amount of out of focus is
>> sufficiently small to not be a problem given the low resolution of the
>> original Optacon retina.  Because of the increased resolution I'm 
>> suggesting
>> in a new design, a better zoom system will be required.  Actually, one of
>> the Optacon prototypes built at SRI and Stanford did have a zoom system 
>> that
>> moved both the lens and the retina to keep the image in true focus.  This
>> did not change the size of the camera and would not be a significant
>> increase in cost after tooling for production.
>>
>>             Various lens modules, such as the typing attachment and CRT
>> screen module, were very important for the Optacon market because they
>> increased employment applications.  While these particular accessory lens
>> modules are not as important today, others could be developed for 
>> producing
>> handwriting, reading LCD screens, viewing and taking pictures at a 
>> distance,
>> etc.
>>
>>             In addition to image signals from the Optacon camera, an
>> independent signal indicating camera movement should be considered. 
>> While
>> sometimes this can be derived from the camera images, there may be
>> situations in which it may be desirable to have signals from the lens 
>> module
>> rollers.
>>
>> V.  Electronics
>>
>>             Since the original Optacon was designed before 
>> microprocessors,
>> the electronics did not include a microprocessor, however Optacon II did 
>> and
>> any future designs most certainly would.  In addition, a new design could
>> include some image storage as well as a port for an external memory
>> stick.  This
>> would enable camera scans to be stored for later retrieval and/or further
>> processing on a PC.
>>
>>             OCR and synthetic speech capability could be built into the
>> Optacon electronics.  These capabilities, together with the storage
>> capability, means that the new design would need to have file handling 
>> and
>> other software built-in.
>>
>>             A very important control on an Optacon is the threshold, 
>> which
>> determines the photocell signal level between black and white. 
>> Especially
>> for poor quality print and for different colored print, how the threshold 
>> is
>> set can determine whether the text is readable or not.  For precision
>> threshold setting, I think this part of the circuitry should be analog 
>> with
>> a high resolution potentiometer.  Unfortunately, in Optacon II this 
>> control
>> was digital with too few bits for precision.
>>
>>             In addition to threshold and tactile stimulator intensity, 
>> there
>> would need to be some additional controls, or buttons, similar to those 
>> on a
>> "point and shoot" digital camera, for deleting images from storage, 
>> cycling
>> through a menu, etc.
>>
>> VI.  Ports
>>
>>             A new design could have a port for the camera (possibly
>> wireless), a port for power (batteries could be charged in the Optacon or 
>> on
>> a separate charging station), a port for a memory stick, and a USB port 
>> for
>> sending camera images to a PC, for enabling the PC to write on the 
>> tactile
>> array, and for enabling new software to be installed in the Optacon.
>>
>> VII.  Battery
>>
>>             The Optacon II design was an improvement in battery 
>> convenience
>> over the original Optacon and a new Optacon design could improve things
>> further.  A system with readily available batteries that the user could
>> easily replace and charge should be the goal.
>>
>> VIII.  Packaging
>>
>>             The Optacon II design was an improvement in packaging over 
>> the
>> original Optacon and a new Optacon design could improve things further.
>>
>> IX.  PC Software for the Optacon
>>
>>             By providing a new Optacon with a USB port where camera 
>> images
>> can be transferred to a PC and the PC can write tactile images on the
>> Optacon means that the basic simplicity of the Optacon can be maintained
>> while providing the possibility of adding many new features for expanding
>> Optacon use.  Some examples are:
>>
>>             A.  Optacon Reading Lessons and Speed Building
>>
>>             Optacon training was essential in producing so many people 
>> that
>> were successful in Optacon use.  Teaching someone to use an Optacon
>> effectively was a labor intensive process.  The most successful Optacon
>> training programs involved one teacher full time for every student for
>> several weeks.  Since the seventies when these programs started, labor 
>> costs
>> have dramatically increased relative to the cost of technology.
>>
>>             However, with the widespread availability and increased
>> capability of PCs, it is now feasible to develop software that could
>> automate at least part of the training process.  The PC could write 
>> letters,
>> words, and text on the Optacon tactile screen, build speed by presenting
>> these at various rates, test student progress, and provide feedback 
>> through
>> synthetic speech.
>>
>> B.  Speech and Braille Output
>>
>>             By OCR processing the images from scans from the Optacon 
>> camera,
>> the PC could provide speech or Braille output.  Several tactile 
>> stimulators
>> could be combined to simulate a Braille dot on the Optacon's tactile 
>> screen.
>> Speech and Braille files could be stored in the PC in addition to image
>> files.
>>
>> C.  Optacon Screen Reader Software
>>
>>             Optacon screen reader software could be developed in which
>> images from the PC screen were displayed on the Optacon tactile array. 
>> The
>> PC mouse could be used to move the field of view of the tactile image 
>> around
>> on the screen.  This could be particularly useful in understanding screen
>> layout, viewing graphics on the screen, and in formatting documents.
>>
>> X.  Conclusion
>>
>>             I believe that developing and disseminating a new Optacon 
>> along
>> the lines described here would significantly enhance the educational and
>> vocational opportunities, as well a personal independence, of blind 
>> people
>> around the world.  I've described a design that would preserve the basic
>> simplicity of the original Optacon, greatly improve the quality of the
>> tactile image, and make tracking along a line of text easier.  By adding 
>> the
>> capabilities of memory storage and communication with a PC, new features
>> could be developed to make reading easier and faster through speech and
>> Braille, and that would expand Optacon applications.  These design ideas
>> need to be evaluated by the blindness community.
>>
>>             My guess is that the development of this basic Optacon alone
>> could cost several million dollars.  (The PC software and other 
>> accessories
>> could be developed later by third parties.)  However, the relatively 
>> small
>> market coupled with the cost of development and the difficulties of 
>> selling
>> to this market will discourage private companies from taking on such a
>> project.  The situation is analogous to that with low incidence diseases
>> where biopharmaceutical companies don't develop treatments unless there 
>> is
>> some consideration such as "orphan drug status".
>>
>>             The hope for bringing back a new Optacon might rest on 
>> obtaining
>> grant support for development and dissemination from private foundations 
>> or
>> government.  For this to be viable would require strong support from the
>> blindness community and leadership from an organization with the 
>> capability
>> of accomplishing the task.
>>
>>
>>
>>
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>
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