Canon Patent Details Constant-Aperture 70-200mm f/2 Design

Asobinet reported that Canon’s patent JP 2026-168807, published October 16, 2026, contains 11 optical examples, including a full-frame 70-200mm f/2 design that stays 240.16mm long through zooming and focusing.

For now, this is a patent document, not a Canon product announcement. The report gives no retail price, mount, launch date or shipment schedule. Asobinet described the filing as combining a 50-80mm f/1.4 design with 70-200mm examples at f/2 and f/1.4.

What the patent specifies

All 11 examples use constant maximum apertures. The drawings provide different focal ranges, dimensions and optical prescriptions:

• Example 1: 51.50–82.52mm at F1.46, a 22.79–14.69-degree half-angle of view, 21.64mm image height, 196.675–198.27mm length and 13.53–13.97mm back focus.
• Example 4: 36.06–82.52mm at F1.46, a 30.97–14.69-degree half-angle, 21.64mm image height, 238.87–238.08mm total length and 13.00–20.85mm back focus.
• Example 6: 36.50–48.44mm at F1.46, a 28.92–23.43-degree half-angle, 20.17–20.99mm image height, 185.01–164.93mm length and 14.58–22.39mm back focus.
• Example 9: 71.65–194.00mm at F2.06, a 16.80–6.36-degree half-angle, 21.64mm image height, 240.16mm total length and 16.24mm back focus. It specifies 23 elements in eight groups, including six aspheric surfaces, and appears to use an internal zoom that keeps the barrel length fixed while zooming and focusing. Its closest focusing distance grows from 0.50m to 1.00m as it zooms in.
• Example 10: 72.00–194.00mm at F2.50, a 16.72–6.36-degree half-angle, 21.64mm image height, 223.00mm total length and 15.51mm back focus.

Focusing is divided among three independent groups positioned toward the subject at close range. The main f3 group carries most of the work; f1 and f2 address field curvature. Their small, light construction means they would not require large motors, supporting the design’s compactness argument.

That is patent-stage engineering, not a published weight or autofocus result.

The filing’s 50-80mm branch is the unusual option. It uses 19 elements in four groups and seven surfaces. Example 6 shrinks from 185.01mm to 164.93mm across its zoom and employs a reduced image circle, which would require in-camera distortion correction.

What does this change for working photographers?

Nothing changes for purchasing, kit budgets or client pricing today. Canon’s RF 70-200mm choices already include f/2.8 and f/4 versions, while EF lenses offer similar apertures in different focal ranges. The broader RF range also includes 35mm, 24-70mm and 100-400mm options.

The source says the current f/2.8 model costs $2,400 and already prices out many enthusiasts. Its $6,000–$8,000 estimate for an f/2 version is speculation, not an announced price; that range would put the lens at roughly two-and-a-half to three-and-a-third times the current f/2.8 cost.

Photographers cited in a Canon Rumors discussion said there would be a “halo lens for portrait photographers,” reportedly covering 70mm, 85mm, 100mm, 135mm and 150mm at f/2. The same discussion hoped for an f/2 trio including 15-35mm and 24-70mm models, reasoning that Canon’s existing 28-70mm makes such a family possible. Neither aspiration constitutes a product announcement.

The report also floats that the design could be “the world’s first 70-200mm,” but provides no comparison or define that claim, making it untestable.

If Canon built the patent as drawn, portrait and wedding photographers could replace several fast primes with one zoom while retaining a shallow depth of field. That is a plausible workflow benefit, not a tested result.

For indoor sports, the report says basketball photographers could gain “more than a stop over f/2.8” in dim arenas. Nominal f/2 versus f/2.8 delivers roughly one stop before transmission or metering effects, and the filing includes no measured performance. Constant maximum aperture would avoid exposure changes while zooming, but sharpness, bokeh quality, autofocus and build weight remain unknown.

The next useful disclosures are Canon’s official specifications, mount, final focal range, weight, price and shipment date; until then, treat the patent as a design signal, not a purchase commitment.