It was used for special effects and some animation techniques and remained an important tool into the late 20th century. Optical printing was not the only option for creating special effects, using projectors on film sets in rear projection and front screen projection setups were also common techniques to combine scenes into one final image.
A previously filmed background scene would be projected onto a large screen from behind the stage, while to a camera on the other side of the screen, actors appeared to inhabit fantastical worlds and noisy situations where trying to record dialogue would otherwise prove fruitless.
Projectors were also a popular practical lighting effect, displaying images directly onto the scenes or actors on camera. Other purely mechanical optical illusions emerged. On one end of the spectrum, the incredibly complex Zeiss Planetarium projectors could recreate the movements of the stars through the night sky on the inside of a large dome.
On the other end of the spectrum, a GOBO disc inserted into a spotlight assembly could create patterns and images for theatrical performance, as well as film lighting effects, mimicking rain, trees, and window frames, or summoning vigilantes. Adding plastic color gels to the GOBO gave it even more flexibility.
Adding color to film projection proved more difficult. This technique built upon the Young-Helmholz Trichromatic Color Theory suggested more than a century prior.
This theory inspired Scottish scientist James Clerk Maxwell to produce the very first color photograph in Four years later, Maxwell went on to revolutionize our understanding of the universe with his Dynamical Theory of the Electromagnetic Field. Maxwell observed that magnetic and electric fields both traveled in waves at the same constant speed as light does. Since these waves move at a constant velocity, different levels of energy manifest as variations in the frequency at which those waves oscillate.
Together, the range of energy levels of these radiation waves is known as the Electromagnetic Spectrum. Most of these waves are not visible to humans. Low-frequency radio waves, microwaves, and infrared waves have the longest wavelengths, and high-frequency ultra-violet, x-rays, and gamma rays have the shortest wavelengths. Between these two ends of the spectrum is a tiny range of electromagnetic radiation frequencies that we know as visible light.
These frequencies stimulate the three unique types of light-sensitive cells in your retina , which we know as cone cells.
Each of the three kinds of cone cells in the human retina are sensitive to a specific range of the electromagnetic spectrum. When a specific frequency of radiation hits one of these cone cells, that sends a signal to the brain , which interprets it as what we know as red.
A different frequency wave hitting a cone cell sensitive to that range tells the brain it has seen blue, and a third cone cell communicates when it comes into contact with green wavelengths of electromagnetic radiation. The sensitivity range of the three types of human cone cells to the visible wavelengths of the electromagnetic spectrum. These distinct color signals are interpreted in the brain as a sum of their parts, like mixing different colors of paint together.
Applying this same additive color strategy to photographic film with different layers of color dyes successfully replicated this phenomenon. Modern photographic film stocks, as well as ink printers, tend to use CMYK subtractive color — in which Cyan, Magenta, and Yellow are removed from White light to render colors, but electronic display systems use the additive RGB color space.
Many of these early color films were positive images, which meant that they could be viewed directly without the need to print them with a photo enlarger. The s also saw the advent of commercial television. In German inventor Paul Nipkow patented his eponymous Nipkow Disc, a simple wheel with a spiral pattern of aperture holes. When combined with newly invented photovoltaic sensors that could convert light into electrical signals, scientists were able to electronically transmit and display simple images with light by As the disc rotated over a thousand times per minute in front of a light sensor, the variations in brightness as each moving point of light passed by were converted into an electric signal, with each hole in the spiral forming one vertical line of the frame from left to right.
This technique was known as raster scanning. Scotsman John Logie Baird experiments with displaying these raster scans by synchronizing a second Nipkow disc and using the encoded light signal to modulate the voltage of a neon lamp behind the viewing disc were known as the mechanical televisor. The image was tiny , particularly compared to the size of the machine itself, and was very high contrast, but it demonstrated an alternative to chemical film.
Instead of rendering each individual frame of an image sequence in its entirety for a fraction of a second like a film system, mechanical television leveraged persistence of vision and the raster scan to record and display just a small portion of the image frame for an even smaller increment of time.
The rapidly changing brightness, synchronized with the spiraling movement of the disc holes, caused the raster scan to appear as one continuous image — though in reality, it was recreating an image point by point , faster than the human eye could perceive. The loud, cumbersome mechanical viewing device was quickly surpassed by a more elegant electronic solution, the Cathode-Ray Tube.
Much like chemical film, the CRT was the result of centuries of research and advances in manufacturing capabilities. In the late 19th century, vacuum tube manufacturing techniques were able to create an atmospheric pressure low enough for scientists to observe a new phenomenon. As more and more gas was pumped from the vacuum tube, the glow moved further and further away from the negatively charged cathode, and in a total vacuum, the tube itself began to glow at the positively-charged anode at the opposite end.
The observation of these cathode-rays was the genesis not just of electronic imaging, but a more concrete understanding of atomic physics.
For centuries, humans had experimented with electricity without fully comprehending the forces they were harnessing. By the mids, scientists were relatively confident that everything in the universe was made of miniscule molecules and even tinier atoms.
In British Physicist J. Thompson successfully measured the mass of a cathode-ray inside a vacuum tube and found that it was times smaller than that of a hydrogen atom. This critical experiment gave us not only a deeper understanding of the building blocks of our universe but also television.
When electrons are shed from a negatively charged cathode and travel towards a positively charged anode in the vacuum of a cathode-ray tube, there are no gas atoms for them to crash into, so they travel in a straight unobstructed line known as an electron beam.
By adding a phosphorescent material on the positively charged side of the vacuum tube and moderating the electrical voltage, researchers were able to accurately control the brightness of the point of light that occurred when the beam of electrons collided with the phosphor coating. An electromagnet placed around the cathode could divert the electron beam to anywhere on the phosphor surface with an electrical signal. This small elementary particle is the force carrier not just for the light that comprises our visible world, but for the quantum mechanical function of the universe.
By rapidly changing an electromagnetic field to direct a sub-atomic beam of electrons onto a reactive phosphor surface thousands of times a second to create photons that combine to form an image, Takayanagi achieved the first electronic illusion of persistent vision in 40 lines of point-by-point resolution. Other systems debuted by Philo Farnsworth and Vladimir Zworykin shortly afterward used electronic technology to capture a raster scan instead of a mechanical Nipkow Disc, but it would be decades before the CRT Television became commercially available in the s.
The concept of using a CRT as a display was also applied to optical projection. With the addition of a lens in front of a small bright CRT, the image could be thrown through space and displayed on any surface, instead of on just a small screen. In fact, limitations in the size of phosphor screens in early CRT televisions meant that most early TV units were projection televisions , which used a lens to throw an enlarged CRT image onto a rear projection screen instead of viewing the phosphor of the CRT directly.
This style of projected television screen was a popular alternative through the end of the 20th century until its eventual replacement by LCD and DLP projectors. Color CRT projectors debuted in the s but were not commonly found for a few more decades. Using three CRTs together , each with their own lens, to project individual RGB channels simultaneously, they could accurately project accurate colors images without loud moving parts or film strips.
The introduction of commercial television inspired some filmmakers to experiment with new ways of projecting images without creating persistent vision. At first, it was limited to monochrome, but by the end of the decade they could show colors, too. Both video players and overhead projectors bring vivid memories of frustrated teachers to life.
How hard it seemed to be, to make sure the video actually played and to make sure the overhead transparent was oriented properly. A lot happened in the history of projection during the s — like the arrival of those gigantic ships of projection that used cathode ray tube CRT to generate the image.
To create color, they had three separate CRTs and their own lens. However, due to the fact that this kind of projector has very specific, high-quality performance attributes deep black levels, no motion blur and long service life as required in several niche applications, they have remained in use much longer. In fact, you can still find simulators using them today.
These projectors were smaller, affordable and digital; all characteristics that are highly appreciated by anyone interested in projection. Today you can find everything from tiny pico projectors the size of a matchbook with a handful of lumens, up to the largest, high-resolution beast boasting up to 60 lumens.
That said, most projector manufacturers have announced or demonstrated 8K resolution projectors. The future certainly looks bright! Topics: dataton , projection , slide projector , CRT projectors. By: David Aleksandersen. David Aleksandersen has extensive experience from the audiovisual industry and is an active blogger. He has been responsible for developing and executing marketing, sales and initiatives in knowledge transfer and partner training for more than 20 years.
This blog is created by Dataton , and is about multi-display software and surrounding technologies, media servers, content creation - basically anything within the AV industry that serves to enrich the audience experience! A short history of projection By David Aleksandersen Slides step forward The era of overheads From CRT to digital Where it all started Roughly we can divide the history of projection into the following eras: Very early projection systems pre-lens projection systems Analog projection lenses and optics Digital projection high-end lenses, optics and illumination sources The history of both analog and digital projection has been heavily influenced by the development of computers.
Magic Lantern The Dutch scientist Christiaan Huygens is generally recognised as the true inventor of the magic lantern, a forerunner of the traditional slide-based image projector.. Episcope The episcope was invented by the Swiss mathematician, astronomer and engineer Leonhard Euler around Le Cinema!
A second series of discs, made in —94, used outline drawings printed onto the discs photographically, then colored by hand. A more sophisticated movie projector was invented by Frenchman Louis Le Prince while working in Leeds. In Le Prince took out a patent for a lens device that combined a motion picture camera with a projector. In , he used an updated version of his camera to film the first ever motion picture, the Roundhay Garden Scene. The pictures were privately exhibited in Hunslet.
The Lumiere brothers invented the first successful movie projector. The first commercial, public screening of cinematographic films happened in Paris on 28 December The cinematograph was also exhibited at the Paris Exhibition of In , digital projectors were being tried out in some movie theatres. These early projectors played the movie stored on a server and played back through the projector.
The images at the time showed pixelization blocks in some scenes, much like images on early widescreen TV's. By , this system had been perfected and there was no trace of pixelization. The systems became more compact from the larger machines of four years earlier. By , movie theatres started replacing the film projectors with digital projectors.
It is believed that by , no more film would be manufactured in the US, and anyone still running it would either be playing old movies or finding a manufacturer outside the US to strike up a new film print. At this point, film projectors are considered obsolete. Click Here to Know about a Legend Dr. Abdul Kalam. Toggle navigation Menu. Social Discuss Sign Up Login. Movie Projector Famous Inventors. Home inventions Movie Projector.
Invented Year. Invention Field. About Invention A movie projector is an opto-mechanical device for displaying motion picture film by projecting it onto a screen. Motion Pictures Charles Francis Jenkins started experimenting with movie film in , and eventually quit his job and concentrated fully on the development of his own movie projector, the Phantoscope.
History The first movie projector was the Zoopraxiscope, invented by British photographer Eadweard Muybridge in Invention of Movie Projector Video. Other inventions in Instruments. Marine chronometer.. Printing press with movable metal type.. Pocket watch.. Stocking frame.. Vernier scale.. Screw micrometer..
Vacuum pump.. Universal joint.. Steam pump..
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