DiRactor™ (Diaphram Refractor) technology forms the basis for Pixera's high-resolution, multi-function digital cameras systems. These cameras are really two cameras in one; they are high resolution digital still cameras and they also function as digital video cameras for video communications applications like videoconferencing or video e-mail. Pixera's DiRactor™ digital camera products use patented optical technology and innovative 100% software image processing to provide customers with an unmatched combination of resolution, image quality, flexibility and price/performance.
Pixera's DiRactor™ based high resolution, multi-function digital camera systems can capture 2-bit RGB color images in resolutions up to 1260x960 pixels using only a 250K pixel CCD and achieve image quality and color reproduction of cameras costing thousands of dollars more.
DiRactor™: An electro-mechanical light refractor that is highly accurate and reliable. Used to shift the incident light from the subject onto the CCD pixel elements.
Pixera Custom Color CCD: A proprietary color filter pattern on the CCD that is designed to work with the light refractor.
Pixera Software Image Processing: Proprietary, 100% software image processing engine that works in conjunction with the CCD filter pattern and light refractor to generate images of excellent image quality and resolution.
Pixera's DiRactor™ light refractor is used when capturing a high resolution image in resolutions of 800x600 or higher. Pixera's current products using this technology can capture color images in 24-bit RGB in resolutions up to 1260x960. And remember - that's the optical resolution.
Pixera's DiRactor™ light refractor consists of a two pieces of optical glass, each surrounded by a small coil of wire and encased in a plastic shell. These two pieces form the diaphragms of the refractor. The diaphragms are separated by a doughnut shaped magnet and these three prices are placed in front of the CCD and housed, along with the CCD, in a plastic case. Our light refractor is extremely accurate to sub-micron distances.
The diaphragms "float" inside the case and the walls of the case have very precise angles. These angles allow the diaphragms to move with very high precision to shift the incident light from the subject onto the pixel elements of the CCD. We use two diaphragms working in tandem because we shift the light both vertically and horizontally onto the CCD during our high resolution image captures.
A very key result of our image shifting technique is that we get two color samples per pixel. Why is this important? We get 2x the color information than our competitors' 1-CCD cameras and as a result we have superior color reproduction and better overall image quality.
There are two main types of image sensors: solid state image sensors, called CCDs (Charge Coupled Device) and CMOS image sensors, usually referred to as "CMOS sensors". Pixera uses CCD image sensors in its cameras because today, CCDs are significantly superior to CMOS image sensors in important areas such as sensitivity, signal/noise ratio, and resolution. CCDs today offer the best combination of resolution and image quality for the price. There are several types of CCDs, usually referred to by their structure. Common CCD types are IT (Interline Transfer), FIT (Frame Interline Transfer), FT (Frame Transfer), and Progressive Scan. Pixera uses the IT type of CCD since it is small, inexpensive, high quality, has high production yields.
For color CCDs, very small micro-filters are placed over the sensor elements in particular checkerboard-like patterns. The two most common types of color filters are Primary Color Filters, RGB (Red, Green, Blue) and Complimentary Color Filters, CMY (Cyan, Magenta, Yellow). Pixera chose to use the RGB color filters, but Pixera has designed a proprietary checkerboard color filter pattern that works with the light refractor and our software image processing to produce images of excellent color reproduction, clarity, and quality.
Essentially, image sensors have sensor elements, sometimes referred to as photo-sensors or pixel elements that are able to convert light energy, "photons," into electrical energy, "electrons". As light hits the photo-sensor, it converts the photon into an electron and holds the electrons in a kind of "bucket" or "well" until emptied. When the sensor element is emptied, this information is converted into an analog signal that represents the raw pixel data from that sensor. It is this raw pixel data that Pixera uses in the next step of its unique process.
The raw analog pixels from the CCD are converted to raw digital pixel data on our interface card using an 8-bit A/D converter. The raw digital pixel data is then sent, uncompressed, into the computer for processing by the image processing engine. By sending raw, unprocessed pixel data, we have the best possible starting point for our image processing.
The final piece of Pixera's unique DiRactor™ technology is our 100% Software Image Processing Engine. This type of technology is unique in the industry today, protected as Pixera trade secrets and it enables Pixera to produce sharp, high quality, color images in resolutions from 160x120 up through 1260x960 pixels.
Current analog and digital cameras today do the image processing in silicon chips, usually called DSPs (Digital Signal Processing) and implemented as ASICs, in the camera itself. There are a wide variety of these types of chips, some designed for particular purposes. The reason that Pixera chose to be different from the rest of the cameras available today is that using software-based image processing we can gain the following advantages:
- Pixera's software-based image processing is more sophisticated, more flexible, and easier to improve and expand its features and functionality.
- Pixera's image processing algorithms is much more complex and detailed than is possible to put into ASIC-based DSPs with today's technology.
- Pixera's software image processing takes advantage of the ever increasing power and speed of today's personal computers. As they gain performance and speed, so do we.
- The same image processing engine is used for video frame processing as well, resulting in excellent video image quality for use with popular video communications applications.
- When capturing a high-resolution picture, 800x600 pixels or above, our camera takes four exposures of the subject. This takes a little under a second.
For each exposure our DiRactor™ light refractor shifts the incident light in a particular direction for a particular distance onto Pixera's CCD pixel elements in order to get four separate and distinct samples for each pixel (4x250K). This process, in conjunction with our proprietary RGB color filter pattern on the CCD results in 2 color samples per pixel sampled. No image processing with the exception of AGC is done in the camera head.
After each exposure, the raw analog pixel data from the CCD is sent to our interface card where all we do is convert the raw analog pixel data into raw digital pixel data. The raw digital pixel data is then sent into the computer, without compression for processing by Pixera's 100% software image processing engine.
The resulting images have excellent image quality and are clean and sharp with the color reproduction of a 2-CCD camera and for much less than a competing digital or analog camera.