Canon's Mastery of Lens Design Technologies Delivers Advanced Performance and Optimized Optical and Ergonomic Advantages in the New KJ17ex7.7B HDgc Lens

Continually refining and advancing the performance of its portable HD zoom lenses for ENG, EFP, and all other production applications, Canon U.S.A., Inc., a leader in digital imaging, at the 2009 NAB Show has introduced a “second generation” member to its line of cost-effective HDgc lenses: the 2/3 inch KJ17ex7.7B.
Since the original introduction of the HDgc line, Canon has listened closely to the users of those lenses. Their feedback, coupled with the recent emergence of even higher performing 2/3-inch HD camcorders for HD ENG, influenced the Company’s design of the all-new KJ17ex7.7B 2/3-inch HDgc lens. The KJ17ex7.7B is a ‘second-generation’ HDgc lens in that it draws upon all that was learned with the original HDgc products to direct an optimized design based upon recent advances in Canon’s computer-based optical design tools and the use of the most contemporary optical technologies. Canon’s new KJ17ex7.7B HDgc lens represents a higher bar in cost-effective imaging value and performance for a wide range of broadcast and professional users.

At NAB 2006, Canon introduced its original line of HDgc portable lenses in response to the introduction of lower-cost tapeless HD ENG cameras from all major manufacturers. This optical line rapidly evolved to encompass the many HD ENG acquisition systems, which soon included cameras having 2/3-inch, 1/2-inch, and 1/3-inch image format sizes, and today there is available a total of 16 HDgc lenses.

“Canon’s HDgc line was instantly well-received,” stated Larry Thorpe, national marketing executive, Broadcast and Communications division, Canon U.S.A. “HDgc is exactly what a rapidly expanding segment of the broadcast and professional video production market is looking for, namely, a line of portable HD lenses designed to suit every one of the new portable HD cameras. HDgc lenses have imaging attributes that match those cameras while offering correspondingly affordable price-points.”

The new generation KJ17ex7.7B lens employs refinements in glass materials and optical coatings with advances in lens element designs, including the use of aspherical elements. The combination of these optical technologies has contributed to improvements in monochromatic defocusing distortions, curvature of field, and comatic aberration, and to a further lowering of longitudinal and lateral chromatic aberrations.

Collectively they enhance the sharpness of the images, especially at the longer focal lengths. The new optical coatings have further reduced flare and consequently enhanced lens contrast. They have also introduced important improvements to the minimization of ghosting artifacts that can be stimulated by strong light sources in the scene. This augments nighttime shooting, which can be very important in ENG.

New Digital Drive Unit Design
The updated design of the Digital Drive unit for the new KJ17ex7.7B is the same as that used on the new HJ14ex4.3B high-performance wide-angle HD EFP lens also being introduced at NAB 2009. The new Digital Drive unit incorporates Canon-developed ultra-compact precision rotary encoders capable of 0.1um position detection. They employ Canon’s unique Micro Roofmirror Array (MRA) technology to produce 16-bit resolution of the positions of the zoom, iris and focus controls. These provide a means by which camera operators can digitally program precise and repeatable settings into their lenses for speed, focus, and iris as well as zoom positions. An information display built into the Digital Drive unit makes precise customization quick and convenient. The new unit extends programmability of all lens operations.

The new Digital Drive unit of the new KJ17ex7.7B lens features an ergonomic design derived from long-term market research by users of all of Canon’s portable HD zoom lenses. Using 3D CAD-CAM programs, Canon significantly improved the tactile interface for the control of zoom, iris and focus. The Digital Drive unit was reduced in width to position the palm of the camera operator’s hand closer to the optical axis, thus reducing the angle at which operators must bend their arm; the result is the alleviation of physical stress during long-term shooting. The curvature of the Digital Drive unit was also optimized to more comfortably fit in the palm of the operator’s hand. Newly developed grip coatings and a new rubber grip support further improve the tactile interface between camera operator and the Digital Drive unit. In addition, the spacing between the focus ring and the Digital Drive unit was widened so operators are less likely to accidentally change settings while manipulating the focus control.

“Canon’s HDgc line of affordable portable HD zoom lenses offers models for every camera-imager size, whether 2/3-inch, 1/2-inch or 1/3-inch,” Thorpe added. “Given the now significant range of HD cameras using 2/3-inch imagers within the new generation of affordable tapeless ENG acquisition systems, we anticipate industry interest in the new KJ17ex7.7B HDgc portable HD lens to be very strong indeed. We plan to extend the family of second generation 2/3-inch HDgc lenses to eventually include wide-angle and telephoto versions.”

See the entire line of cost-effective portable HDgc lenses and other HD lenses and products from the Broadcast and Communications division of Canon U.S.A. at the 2009 NAB Show, April 20-24, at exhibit number C4325, in the Central Hall of the Las Vegas Convention Center.