Canon Patent - EF 1000mm f/5.6 DO IS Lens

Canon EF 800mm f/5.6L IS lens

My readers know I am a fan of Canon's Diffractive Optics technology. The current EF 400mm f/4 DO IS II is my favorite Super Telephoto lens when I want to travel light on my wildlife photography tours. You can see my equipment bag and works on MichaelDanielHo.com. Canon has been working to perfect the DO technology since the first EF 400mm f/4 DO IS lens came out in 2001. The EF 600mm f/4 DO BR lens was showcased in last year's Canon EXPO at New York City.

In April, a new Canon DO patent has been uncovered for the APS-C sensor. The new design has a focal length of 50-300mm f/4.5-6 with STM. The current EF 800mm f/5.6L IS is Canon longest Telephoto lens. It is heavy and the technology is aging. Canon has been toying with the ideal of replacing it with a Series II model. But now another DO patent has been discovered by Egami. It is the EF 1000mm f/5.6 DO IS lens.

This will be ultimate in Super Telephoto Diffractive Optics design. If Canon can bring this lens out with a top weight of around 8 to 9 pounds and pack it with the latest DO BR technology, I will be a buyer for sure. Nikon saw the value in DO lens design last year but is much further behind than Canon in this technology. They announced the Phase Fresnel (PF) 300mm f/4 lens in January 2015. Fresnel lenses were originally developed by the French physicist, Augustin-Jean Fresnel for use in lighthouses.


Patent Publication No. 2016-102852 (Google Translated)

• Published 2016.6.2
• Filing date 2014.11.27
• Zoom ratio 1.00
• Focal length 950.00
• F-number 5.80
• Angle of view 1.30
• Image height 21.64
• Overall length of the lens 485.94
• BF 0.40
• Canon patent
• Positive and negative Shibomake
• Diffractive optical element (first group)
• Inner focus (the second group)

Nikon Patents 24-70mm f/2.8 Phase Fresnel Lens

Apparently Nikon has seen the light and is trying to play catch up to Canon's Diffractive Optics lens lineup. A newly discovered patent shows a Nikkor 24-70mm f/2.8 lens with a Phase Fresnel element although it was filed back in May, 2014.

Fresnel lenses were originally developed by the French physicist, Augustin-Jean Fresnel for use in lighthouses. Unfortunately for Nikon, they have been surpassed by Canon since 2001, when the EF 400mm f/4 DO IS lens came out. Utilizing Diffractive Optics technology, the Canon glass is much lighter than other prime lens with the same focal length and speed.

I have owned this lens for over a decade and although it is not the sharpest in Canon's EF lens line up, the speed and versatility outweigh the disadvantage. Thankfully, Canon released the Series II version of this lens - EF 400mm f/4 DO IS II a few months ago. I have taken delivery and it is a big improvement over the original model. This is my favorite Super Telephoto lens for handheld wildlife photography. By the way, Canon has already patented more DO lenses for future developments.

Nikon plans may also include a 200-400mm f/4-5.6 , 16-30mm f/4.3-5.6 , and a wide angle, tilt-shift PF lens in the future. Their Phase Fresnel (PF) 300mm f/4 lens was announced in January of 2015. Weighing approximately 1.66 pounds (755 grams), the new lens is a light weight, full frame, prime lens.