The Remarkable Inventions of Dr. Dave Luce: Physicist of Sound, Sight, and Synthesis

– by Ben Luce


David A. Luce (1936-2017), my father, known affectionately to most of his colleagues as “Dr. Dave,” was a physicist turned inventor who is known in various fields of research and technology for 1) his pioneering research on the structure of musical tones, 2) his design of important analog synthesizers, e.g. the Polymoog. Taurus Bass Pedal Synthesizers among others, and 3), and quite incongruously, his invention of revolutionary, sight-saving ophthalmic technology. All told, his work exerted, and still exerts, a significant influence on the sound of the music we listen to, and on our visual health. Although relatively unsung, and in some quarters badly misunderstood and under appreciated, he deserves to be remembered as one of the great scientists and inventors of latter half of the 20th and early 21st centuries. A list of patents and publications appears at the end on this page from which one can quickly gain an overall sense of his work. Or simply read on! I am presently preparing a full biography of his life and works, to be released sometime in the relatively near future, but I provide below a brief overview here of his major accomplishments, along with some resources, and also discussion regarding various external issues surrounding his prolific work, which will hopefully alleviate some misunderstandings that have been propagated by others.

Although very prolific in his work, I also want to emphasize his character right at the outset. David Luce was a humble person, and also extremely generous and ethical. He was as deeply devoted to family, friends, and his coworkers as to his technical interests and pursuits. Indeed, I believe a great deal of his success as a scientist and an inventor is rooted in his ethical standards and devotion to those around him. As such, he is dearly missed by his surviving family and friends, and scores of people with whom he worked closely with and in many cases mentored or went out of his way to support in other ways. He also had a wry sense of humor.

Philosophically, besides being an ardent believer in the power of the scientific method to unearth truth, he was a dedicated humanist, in the tradition of Bertrand Russell and progressive thinkers such as Prof. Robert LeFevre Shurter, whom he interacted with at Case Institute. Consistent with this, he was actively committed to avoiding corruption and exploitation in the business environments he worked in, and to community service, civil rights, and environmental protection. And although he became highly educated, and achieved some positions of significant stature and influence, he did not forgot his humble origins, and was not an elitist, or ambitious about seeking wealth, credit, or fame. He consistently turned down lucrative offers from large corporations to pursue the things he thought meaningful and worthwhile. and to utilize his knowledge and abilities for the benefit of all.

These positive personal traits were no accident: His parents, Paul and Grace Luce of Struthers, Ohio, who were school teachers, and Paul a principal later in his career, were dedicated community volunteers and leaders themselves, to a rather extreme degree, and deserve the credit for imbuing their children (David and daughter Nancy) with their values and with their zeal for education. David was thus an extremely good student throughout his school years, enabling him to earn scholarships and attend college at Case Institute and then graduate school at MIT. Crucially though, he was also very independently minded and extremely inquisitive and creative: He was the quintessential mad-scientist kid of his neighborhood, spending endless hours in his laboratory in his parents basement conducting all manner of experiments, taking apart and reassembling every device he could lay his hands on, and creating new devices (e.g. Tesla coils and such) thus preparing himself for a dual life later on both scientific research and invention.

Finally, David was an absolute fireball of energy and concentration, throughout his entire life, even when at play. He had a crazily strong work ethic, and never stopping inquiring about nature, creating, and working to further his knowledge, research, and inventions. His last patent was finally awarded three years after his passing.

Four Careers

By his own count, my father’s work effectively spanned four separate careers, not counting some intermediary adventures in other areas which are omitted here for brevity:

1) Pioneering Physicist of Musical Sound

In a moment of inspiration in 1959 after encountering a notice on a bulletin board, David Luce, then a relatively new graduate student at MIT, abruptly turned his back on nuclear physics, and with it the world of Cold War physics in general – with which he had growing ethical concerns – and decided to devote himself to uncovering the physics of musical sound instead. At the impetus of his new thesis advisor in this area, one Dr. Melville Clark Jr., he pioneered the use of computers, which at that time were giant, punchcard driven machines, to carry out the first fully rigorous and truly comprehensive analysis of the structure of the musical tones. His Ph.D. thesis analyzed no less than 14 different orchestral instruments in depth, using an exhaustive sample set of tones that he obtained by recording musicians playing uncomfortably in an anechoic chamber. This project proved to be a herculean effort at the time given all the inherent technical challenges he encountered, but his persistence ultimately resulted in a voluminous thesis (provided below) that reads like a veritable textbook on musical acoustics, and also experimental technique, and which is still an informative read today due to the plethora of accurate and useful information it contains.

Having become a master of those giant computers and the special data processing techniques he specially developed for this task, and given the departure from MIT of his initial advisor, he also provided extensive assistance to his fellow graduate students, gratis, in completing their studies as well on many other musical instruments, which effort helped launch a number other careers, and fleshed out the overall contribution that the project made to our collective knowledge of musical tones.

The key insights into musical tones revealed in his own thesis, particularly those related to the evolution of harmonics, attack and decay envelopes, and spectral formants, subsequently spread like wildfire through both scientific and electronic music circles, and exerted a significant influence, both direct and indirect, on the development of signal analysis methods, on electronic music creation by various composers, and on the development of electronic music synthesizers. This includes, I have good reason to believe, some indirect influence on the development of the Moog Ladder Filter, with occurred through Robert Moog’s interaction with music acoustics researcher and synthesizer experimentalist James Beauchamp at the University of Illinois, who was strongly influenced by David’s work. The following photos capture some of the above described history:

The Thesis:

2. Inventor of Powerful Synthesizers, pre-Moog Music

David then went on, from 1964-1971, to invent some of the most innovative and powerful analog synthesizers ever invented, working essentially solo in a tiny lab in Wayland, Massachusetts at the behest of his original thesis advisor and now employer, Dr. Melville Clark Jr.. It had been Clark’s intent all along to invent electronic keyboard instruments, even though he lacked the expertise in electronics himself to do so. David hence embarked on an intense program of research and develop to carry out the circuitry design and sound development tasks, which included some important work extending his Ph.D. research (published in several influential papers with Clark), and even created much of his own equipment, including inventing some new technology for rapid signal analysis (see the paper “A Real-Time Multipartial Waveform Analyzer-Synthesizer, Luce and Clark, 1968). Clark and David together decided which features the instruments would have as they proceeded, and David did all the circuit design work. The project was extremely ambitious in scope, covering extensive development in both analog and digital circuitry, and also specialized keyboards and sonic control devices of various sorts.

Although never commercialized due to inexplicable reluctance and backpedaling on the part of Clark – even despite some of successful attempts by David to attract investment – the instruments that David invented in this context were truly remarkable in terms of their ability to mimic the complex timbres and performance characteristics of orchestral instruments (something Clark specifically wanted him to focus on, and only on). The following sound file provides a short sample recording of one of these instruments, recorded circa 1969. This was performed by composer Harold Shapiro, a close friend of David’s and the overseer of the electronic music studio at Brandeis University at the time. The first segment utilizes a french horn tone generator. Note that it is fully polyphonic as well. The second uses a trumpet tone generator. You can verify that the sounds mimic the real instruments very convincingly, almost to the point of sounding like a sampler, even though this is in fact be accomplished with analog synthesis:

It was a real tragedy for David, and for history, that these instruments were not commercialized, as their impact on the music world would surely have been great. On the other hand, this work prepared David thoroughly for his later work with Moog Music, even though David had to invent completely new circuitry for that, and so still has great technical and historical significance. These instruments also likely had some strong influence on certain other synthesizers being developed by others at the time, particularly the Arp Soloist, due to some exposure provided to visitors to the Luce-Clark Lab.

Although they utilized analog synthesis entirely, these instruments were also remarkable for their digital control circuitry. The latter included both presets and other functions, and also the digital scanning keyboards. David in fact independently invented the “scanning keyboard” approach to synthesis long before it became the basis of other synthesizers in the late 1970s, with enormous although not widely known consequences for the entire history of polyphonic synthesizer development thereafter in terms of the largely hidden world of patent claims and fights – a story I plan to shed more light on in the future.

Finally, David also invented keyboard mechanisms and other control mechanisms for creating a high level of expressive control for players. Expressive control was in fact a major focus of the work of Luce & Clark.

Here are a few slides showing some of the digital architecture and analog circuitry from these instruments and one of the keyboard mechanism schemes, drawn from the patents which bear David and Mel Clark’s names, which were primarily drawn and written by David:

  • A flow diagram for a generalized tone generator. Note the "Burple Generator," a circuit used to create the complicated attack properties at the beginning of a note played by, for example, a trumpet.
  • Schematic of keyboard scanner. For creating a polyphonic synthesizer from a collection of tone generators.

3. Synthesizer Design and Leadership at Moog Music Inc.

After a short stint at Sperry Rand to pay the bills, Robert Moog invited David to join him in 1972 at what would soon become Moog Music Inc. Here he we go on to contribute several important synthesizer designs and numerous synthesizer design ideas to other Moog synthesizers, and he also oversaw the engineering department as a whole (1972-1981), served a president of the company (1981-1983), and finally became co-owner/CEO of Moog Electronics Inc. (1983-1987). The latter was actually a desperate and moderately successful attempt that he and the company’s CFO Mr. Scott Chapman organized to save the company, and in particular to save the many jobs the company provided, from all-but-certain liquidation after Moog’s parent company, Norlin Corporation, gradually collapsed under a combination of fatal management errors and a hostile takeover attempt.

Some of the specific contributions David made at Moog Music include:

  • Essentially saving the company early on with a crucial fix to the Minimoog after the production line had been shut down for weeks after many units had suddenly started behaving erratically in the field due to a design error by Robert Moog, and after Moog had been unable to diagnose the problem for several weeks.
  • Various design contributions to the Minimoog and also to Moog Modular systems, including designing the 1150 Ribbon Controller, and thereby helping to extent their commercial viability and quality.
  • Improving the Sonic Six Synthesizer, in collaboration with Robert Moog, making the Mark II version of this synthesizer a much more reliable and better instrument.
  • Contributing key design elements to the Lyra Synthesizer (otherwise designed by Robert Moog), one of which, the touch sensitivity, played a major role in the sound of the instrument as utilized the work of Emerson, Lake, and Palmer.
  • Contributing important electronic design innovations to the Micromoog, Multimoog, and virtually all other Moog Synthesizers.
  • Famously inventing the Polymoog. This was in fact, and despite various misrepresentations propagated by some, one of the most innovative and rich sounding polyphonic synthesizers ever created, including for subtle sonic reasons that few are aware of today (but which are described in the patents). This instrument, despite some genuine reliability issues not related to its electronic design, was also a huge musical and commercial success for Moog Music.
  • Invention of the Taurus Bass Pedal synthesizer (and collaborating with Tony Marchese on the mechanical design), a very influential and good sounding synthesizer that also pioneered digital presets for Moog Music and unparalleled tuning stability.
  • Electronic design of the Opus III polyphonic keyboard, a good sounding, innovative, and solid string/brass keyboard. (The concept of the Opus was proposed by Herb Deutsch).
  • Invention of the “digital scratchpad” approach to digital patch memory, which approach is realized in the Source and Memorymoog Synthesizers, and which Jim Scott first helped flesh out into a prototype monophonic “Memory Moog” that unfortunately did not see production.
  • Thorough and meticulous management of Moog Music’s Engineering Department overall from 1972 to 1981, and then of the whole company from 1981-1987, including co-founding and directing Moog Electronic Inc. This work included extensive mentorship and guidance of other engineers at Moog Music Inc., and myriad special projects as demanded by the circumstances of the time.

Finally, I would like to emphasize that none of the above mentioned work at Moog Music Inc, or the work at Reichert Inc. described below, happened in isolation. Developing and manufacturing commercially viable synthesizers, especially in the 1970s, required teams of people working in close collaboration, and overcoming myriad of challenges. My father was a team player through and through: Although he spent much time alone experimenting with circuitry and such, as was necessary sometimes, he also collaborated closely and enthusiastically with his colleagues, with whom he generally also developed deep and lasting friendships. Although this article focused mainly on his accomplishments, he deeply appreciated and loved his colleagues, and considered their work as important and as worthy of attention as his own. In the biography I am writing of his life and work, I accordingly devote substantial space to the work of others, to the extent I’m able to accurately describe it.

Here though is an (undoubtably incomplete) list of some of David’s colleagues at the original Moog Music, in last-name alphabetical order, and with my sincere apologies for any accidental omissions—omission here does not imply anything about the importance of anyone’s role in the company. May their fantastic accomplishments and contributions be forever remembered:

Jon Beers (Technician); Mike Bucki (Engineer); Ray Caster (Technician); Scott Chapman (CFO); Roger Cox (Engineer); Ray Denison (Engineer); Herb Deutsch (Marketing Director); Tom Gullo (Manufacturing Manager); Bob Hackett (Musician); Robbie Konikoff (Artist Relations); Roger Luther (Quality Control); Anthony Marchese (Mechanical Engineer); Robert Moog (Originator, Engineer, Physicist); Chris Percival (Engineer); Dan Pierce (Engineer); Val Podlasinski (Clinician, Marketing); Thomas L. Rhea (Vice President of Studio Systems); Dick Schlerf; Jim Scott (Engineer); Art Siriani (Draftsman); Ray Updike (Sales Manager); David Van Koevering (Sales Director); Rich Walborn (Engineer); Rock Wehrmann (Clinician, Marketing).

4. Revolutionary Opthalmic Technology

After the demise of Moog Electronics in 1987, which was one of the most stressful and painful periods of David’s life, David executed another remarkable career shift in midlife, and set about performing R&D work in ophthalmic technology for American Optical Inc, which morphed into an offshoot of American known today as Riechert Inc. With his incredible focus and work ethic, he quickly became a lead developer in the field, and made numerous contributions to improving Riechert’s products and inventing new ones.

In the year 2000 he made a discovery about a device called the “air puff tonometer,” which he had been working to improve at the time, and with a decade or so ended up completely revolutionized the field of ophthalmology by introducing the notion of “corneal hysteresis” along with a special device known as the “Ocular Response Analyzer” or “ORA” to measure it. This was essentially an improved air puff tonometer that also processes the data differently to measure corneal hysteresis. He then spent years collaborating with various other researchers and practicing ophthalmologists to collect clinical data, write papers, etc. This, and the other devices his work spurred other companies to develop, and the general reinforcement of a growing suspicion among researchers at the time that the cornea is actually viscoelastic, not just elastic (essentially meaning it transforms some mechanical energy into thermal energy when stretched instead of just storing it like a stretched spring), has now led to a major improvement in the ability of ophthalmologists to accurately diagnose eyesight disorders such as glaucoma in general. David is therefore remembered today as the “Father of Corneal Hysteresis” by experts in the field.

David at work in his lab at Reichert Inc., testing out his Ocular Response Analyzer apparatus, which sits to his right.

All was not smooth sailing however: Technological change does not come easily sometimes. In addition to doing all this research and development work, David and his colleagues at Reichert, especially David Taylor, and their colleagues in the research community at large, were obliged to carry out a decade plus long battle to win official acceptance and support for the ORA and his corneal hysteresis concept by the medical community against an entrenched faction of the industry that was still devoted to a now obsolete technique for measuring interocular pressure (the Goldman Tonometer). And all while the value of his work at Riechert Inc was called into question while managers waited impatiently for his innovation to produce actual profits.

After this, David continued research on corneal hysteresis, chasing down a profound intuition that he had regarding the connection between energy and life, until nature herself prevented him from continuing further in November, 2016. He finally passed on April 15, tax day, 2017. 

The following shows a few excerpts from a textbook on Corneal Biomechanics containing a chapter dedicated to the ORA:

The Patents

David has many patents to his name, all of which can be obtained publicly from the US Patent Office, and which form a useful and important record of his work:

  • Signal Processing Utilizing Basic Functions
    • M Clark Jr, DA Luce – US Patent 3,697,703, 1972
  • Signal Generator for Electronic Musical Instrument, Employing Variable Rate Integrator
    • DA Luce – US Patent 3,943,456, 1976 
  • Helically Wound Pitch-Determining Element for Electronic Musical Instrument
    • DA Luce – US Patent 3,997,863, 1976 
  • Wide Dynamic Range Voltage Controlled Filter for Electronic Musical Instruments
    • DA Luce – US Patent 3,974,461, 1976 
  • Musical Instrument with Means for Scanning Keys
    • M Clark Jr, DA Luce – US Patent 3,968,716, 1976 
  • Electronic Musical Instrument with Exponential Keyboard and Voltage Controlled Oscillator
    • DA Luce – US Patent 3,991,645, 1976 
  • Preset System for Electronic Musical Instrument
    • DA Luce – US Patent 3,981,218, 1976 
  • Keyboard for an Electronic Musical Instrument Employing Variable Capacitors
    • DA Luce, A Marchese – US Patent 4,027,569, 1977
  • Multiplexer for Electronic Musical Instrument
    • DA Luce – US Patent 4,028,979, 1977 
  • Foot Control Apparatus for Electronic Musical Instrument
    • DA Luce, A Marchese – US Patent 4,046,049, 1977 
  • Electronic Musical Instrument with Dynamically Responsive Keyboard (Polymoog related)
    • DA Luce – US Patent 4,099,439, 1978
  • Electronic Musical Instrument Capable of Generating a String Chorus Sound (Polymoog related)
    • DA Luce – US Patent 4,145,943, 1979 
  • Electronic Musical Instrument Capable of Generating a Chorus Sound (Polymoog related)
    • DA Luce – US Patent 4,228,717, 1980 
  • Memory Override System for Programmed Electronic Synthesizer
    • JL Scott, DA Luce – US Patent 4,291,604, 1981
  • Voltage Controlled Attenuator
    • DA Luce – US Patent 4,334,195, 1982 
  • Synthesizer Preset Editing Techniques
    • DA Luce, J Scott – US Patent 4,352,311, 1982
  • Musical Instrument
    • M Clark Jr, DA Luce – US Patent 4,365,533, 1982
  • Musical Instrument
    • DA Luce – US Patent 4,463,647, 1984 
  • Musical Instrument
    • M Clark Jr, DA Luce – US Patent 4,503,745, 1985
  • Optical Alignment System
    • DA Luce, S Krstanovic – US Patent 4,881,807, 1989 
  • Method And Apparatus For Determining The Optical Properties Of A Lens
    • CJ Percival, DA Luce – US Patent 5,301,004, 1994 
  • Instructive Display For Assisting in Centering An Optical Path Element On A Path
    • DA Luce, CJ Percival – US Patent 5,446,274, 1995 
  • Joystick For an Ophthalmic Instrument Where Vertical Movement is Controlled by Rotating The Joystick
    • DA Luce, JL Zelvin – US Patent 5,471,260, 1995 
  • Joystick Override Control For An Ophthalmic Instrument
    • DA Luce, DE Miller – US Patent 5,587,748, 1996 
  • Tonometer Air Pulse Generator
    • DA Luce – US Patent 5,779,633, 1998
  • Keratometric Illumination System
    • DA Luce, JL Zelvin – US Patent 5,825,457, 1998 
  • Applanation Detection System For A Non-Contact Tonometer
    • DA Luce – US Patent 5,954,645, 1999
  • Non-Contact Tonometer Having Non-Linear Pressure Ramp
    • DA Luce – US Patent 6,159,148, 2000 
  • Automatic Optometer Evaluation Method Using Data Over a Wide Range of Focusing Positions
    • DA Luce, M Severns – US Patent 6,042,232, 2000 
  • Non-Contact Tonometry Method
    • DA Luce – US Patent 6,419,631, 2002
  • Hand-Held Non-Contact Tonometer
    • CJ Percival, DH Hoover, DA Luce – US Patent 6,623,429, 2003
  • Method for Optimizing Piston Diameter In A Non-Contact Tonometer, And Non-Contact Tonometer Having Fluid Pump Designed By Said Method
    • B Siskowski, DA Luce – US Patent 6,616,609, 2003
  • Method for Eliminating Error In Tonometric Measurements
    • DA Luce – US Patent 6,817,981, 2004 
  • Non-Contact Tonometer Having Improved Air Pump
    • DA Luce – US Patent 6,726,625, 2004 
  • Duel Mode Non-Contact Tonometer
    • DA Luce – US Patent 6,875,175, 2005 
  • Method and Apparatus for Measuring Biomechanical Characteristics of Corneal Tissue
    • DA Luce – US Patent 7,004,902, 2006 
  • Method and Apparatus for Determining True Intraocular Pressure
    • DA Luce – US Patent 7,481,767, 2009
  • Method and Apparatus for Measuring Corneal Resistance
    • DA Luce – US Patent 7,798,962, 2010
  • Method and Apparatus for Tear Film Measurement
    • DA Luce – US Patent 7,771,353, 2010 
  • Method and Apparatus for Determining True Intraocular Pressure
    • DA Luce – US Patent 7,909,765, 2011
  • Subsystems and Methods for Non-Contact Corneal Deformation
    • DA Luce – US Patent 8,613,704, 2013
  • Ophthalmic Diagnostic Instrument and Method
    • DA Luce – US Patent 9,320,430, 2016
  • Tonometer Calibration Tool
    • R Bonaventura, DG Kelkenberg, DL Beverly, DE Miller, DA Luce – US Patent 9,289,124, 2016
  • Determination of Continuous Dynamic Corneal Viscoelastic Bending Moduli
    • DA Luce – US Patent 10,806,342, 2020


As his work dealt more with invention than with research on the whole, his publication list is not long as compared with many scientists. But some of his papers, and his thesis, were nonetheleess quite influential:

Theoretical Calculation of a Magnetic Field. D.A. Luce. Honor’s thesis at Case Institute of Technology, 1959.

 Alternating Current Spark Generator for the Elementary Physics Laboratory, KW Billman, JD Hayden Jr, RC Levine, and D.A. Luce,  American Journal of Physics, 29, 367, 1961. 

Computer Controlled Printing, MP Barnett, DJ Moss, DA Luce, KL Kelley, Proceedings of the Spring Joint Computer Conference, 263 IFIPS, 1963. 

Practical Operating Experience with a Tape Controlled Photon S-560 Unit, DA Luce, MP Barnett, Automation and Scientific Commun.(See Am. Doc. 7/64—151.) This apparatus has been in use at Cooperative Computing Laboratory, Mass. Inst. of Tech., since April. 1963.

The TYPRINT System, MP Barnett, DA Luce – 1963 – MIT Cooperative Computing.

Physical Correlates Of Nonpercussive Musical Instrument Tones, Ph.D. thesis, MIT, DA Luce – 1963

Preliminary Experiments on The Aural Significance of Parts of Tones of Orchestral Instruments and On Choral Tones, M Clark Jr, D Luce, R Abrams, H Schlossberg… – Journal of the Audio Eng. Society, 11, 182, 1963.

Computer Generation of Photocomposing Control Tapes. Part II. The PC6 System, MP Barnett, DJ Moss, DA Luce – Journal of the Americas, 1964

A Preliminary Experiment on The Perceptual Basis For Musical Instrument Families, M Clark Jr, PT Robertson, D Luce – Journal of the Audio Engineering, 12, 199, 1964.

Duration of Attack Transients of Nonpercussive Orchestral Instrument, D Luce, M Clark Jr – Journal of the Audio Engineering Society, 13, 134, 1965.

Intensities of Orchestral Instrument Scales Played at Prescribed Dynamic Markings, M Clark, D Luce – Journal of the Audio Engineering Society,  13, 151, 1965.

Physical Correlates of Brass Instrument Tones, D Luce, M Clark Jr – The Journal of the Acoustical Society of America, 42, 1232-1243, 1967.

A Real-Time Multipartial Waveform Analyzer-Synthesizer, D Luce, M Clark Jr Journal of the Audio Engineering Society,  17, 439-444, 1968.

Computer Controlled Printing, MP Barnett and DA Luce, MIT Academic Press, 1969.

Dynamic Spectrum Changes of Orchestral Instruments, DA Luce – Journal of the Audio Engineering Society, 23, 565,1975.

Time-Domain Measurement of Loss and Dispersion, DA Luce, HM Cronson and P.G. Mitchell, IEEE Transactions on Microwave Theory and Techniques, Jan.  50, 1976

Reichert Ocular Response Analyzer Measures Corneal Biomechanical Properties And Iop, D Luce, D Taylor – Reichert Ophthalmic Instruments, 2006.

Determining In Vivo Biomechanical Properties of The Cornea With an Ocular Response Analyzer, DA Luce – Journal of Cataract & Refractive Surgery, 2005 – Elsevier.

New Dynamic Corneal Biomechanical Parameters Derived From Curvature Versus Pressure Analysis of  Ocular Response Analyzer (Ora) Data, DA Luce – Investigative Ophthalmology & Visual Science, 2016.

Ocular Response Analyzer, D Luce, D Taylor – Corneal Biomechanics: From Theory to Practice, 2016.