Who Invented The Overhead Projector?

Who invented the overhead projector?

Amidst the continuing growth of the projector technology, one important thing that should be remembered is that the inspiration and insight that created LCD and DLP projectors can all be traced to that almost forgotten technology known as the overhead projector.


Regardless of how far apart the gap in technology has grown since the overhead projector reigned supreme, those among us who have developed a fondness for the big bulky lighted box with the gooseneck and transparencies simply do not want to let go that easily.

This little bit of history is for those who grew up in the mid-80s to late 90s and benefited tremendously from the limited but useful warmth of the overhead projector to which all modern projectors owe their existence.

The idea for the overhead projector has floated around for ages but according to scientific historians, there is no definitive account that pegs the invention of the overhead projector to one moment in time.

Simply put, ideas were built on top of each other to create the not-so-modern overhead projector which eventually paved the way for the LCD and DLP devices today.

According to historical accounts, a device closely resembling the overhead projector known as the episcope first found use in the 1900s. It had the same function as the overhead projector and was designed using the same concepts of bending and reflecting light.

However, its use of multiple lenses to direct light into to the projector screen from which the image can be viewed made it complicated to operate and set up. The episcope also had one glaring weakness; while it excelled in projecting the image of opaque materials, it was incapable of capturing the essence of transparent images.

Naturally, the epiadiscope superseded the episcope soon after by being able to project both transparent and opaque images using one device.

A more ‘modern’ incarnation of the overhead projector eventually found practical application in the US military in the 1940s. That same institution that gave birth to many modern amenities and applications also had a hand in developing the premier presentation device of the 20th century.

Obviously, the military found it a problem to brief hundreds of servicemen in one large hall without the benefit of a device that can project images into a bigger screen. It was during this time when the practical use of the projector was born and distilled into a device that uses a 9-inch stage with a cellophane roll as a medium for transferring more detailed images into the viewing screen.

Not long after, in the 1950s and 1960s, the design of the projector made the leap from the war rooms and mess halls to the classrooms and boardrooms of education institutions and business offices. The growth was sparked by the efforts of 3M and Buhl Industries who pioneered mass manufacturing of projector machines to a very demanding market.

However, before all of these happened, executives in both companies needed some amount of convincing as to whether the device was really going to be sellable or it was just another fad not worthy of capital investment in manufacturing operations.

Roger Appledorn was just another employee in 3M’s Thermal Fax section until the projector gave him a calling for which the rest of the world will be forever thankful. Appledorn was more than game in putting the necessary effort to convince his superiors at 3M that the projector serves a real need. At the very least, it can be used in bigger rooms when chalkboards are not as effective. At its very best, it can totally render chalkboards and messy chalk moot.

Not long after Appledorn’s inspired sales pitch, the overhead projector became a staple in many classrooms and boardrooms. It stood witness to the genius of many graduates in the 1980s and 1990s and the subsequent birth of the Dotcom era soon after.

Through every overhead projector in this period, ideas flowed and business agreements were forged paving the way for the world we live in today. The overhead projector made further leaps in technology evolving from monochrome to full colored models, more powerful lights, more refined projector lenses, less noisy fans, and relatively lower power consumption.

Still, every good thing has to come to an end and the overhead projector met its demise as the demand for more fluid displays came with the advent of video and computer graphics. In the mid-1990s when Microsoft released multiple installments of the now ubiquitous Microsoft computer operating systems, the overhead projector was slowly edged by more sophisticated products that fully supported video and animation displays. The modern devices also seamlessly worked with computers, something that overhead projectors weren’t able to achieve in the time of its reign.

Today, the overhead projector is relegated to the dusty confines of basements by many previous owners who have since moved on to more fascinating and capable technology. Consequently, the only remaining organizations that continue to use overhead projectors are located in third world countries where modern LCD and DLP projectors continue to remain relatively expensive.

Still, the good run that the overhead projector had is more than enough blessing to the many that were touched by its warm glow one way or another. The overhead projector aptly bridged the transition from a post-war era to a time of immense business growth, through it all patiently displaying the ideas that would shape our world to what it was today.

Because of Mr. Appledorn’s efforts, we were momentarily gifted by the services of the overhead projector. And while it may now seem too antiquated using today’s standards, it is hard to argue that not too long ago, it was as useful as any other device that was introduced to the market. It may not have been fancy, but it was definitely useful, and for that we say our last ‘thanks’ and bid our byes to the legacy of the overhead projector.