Eiki AH-B22020 Zoom Standard-Throw Lens for EK-800U

Eiki Original Lens AH-B22020 Zoom is an original optical accessory for Eiki engineering projectors. It is a Standard Throw lens with a throw ratio of 1.02-1.36:1. The official compatibility list covers 1 model; before installation, simply verify the projector model and panel size, with no need to make do with adapter rings. The value of an original lens lies not in the extra rows of specifications, but in the fact that it is calibrated at the factory to the optical path and mount of that model series: the image circle, edge illumination, and focusing travel all meet their design values, so there is no need to use keystone correction to compensate for image quality.

1. Lens Specifications

Brand	Eiki (Eiki)
Lens Model	AH-B22020 Zoom
Throw Ratio	1.02-1.36:1
Product Type	Standard Throw
Compatible Models	1 projector
Warranty	12 months; damage not caused by the user is eligible for after-sales service, subject to the date shown on the shipping documents

These specifications are subject to the manufacturer's specifications. For mechanical dimensions, flange distance, and mount type not shown in the specifications table, please verify them with us based on the projector model. Ordering directly based on a similar model carries the risk that the lens will not fit.

2. Converting Throw Ratio into Installation Distance

The throw ratio is the ratio of the installation distance to the image width. This original zoom lens (1.02-1.36:1) supports a range of installation distances for the same image size and can be focused anywhere within that range during installation.

Image Size	Image Width	Required Installation Distance
100 inches	2.15 m	approx. 2.19 – 2.92 m
120 inches	2.58 m	approx. 2.63 – 3.51 m
150 inches	3.22 m	approx. 3.29 – 4.39 m
200 inches	4.30 m	approx. 4.39 – 5.85 m

These distances represent the clear distance from the front surface of the lens to the screen and do not account for rear housing clearance for heat dissipation and cable connections. Calculated for a 16:10 image, actual distances should be verified on site and according to the manufacturer's manual.

Image quality differs at the two ends of the zoom range: toward the close end, the image is brighter and the edges are slightly softer; toward the far end, the edges are sharper and brightness decreases slightly. Where the venue allows, the middle of the range is recommended. After installation, first find the sharpest position on the focus ring, then fine-tune the shift.

3. Compatible Models (1 Model)

The table below is taken from the official compatibility list. Brightness and resolution are populated from the model database; unavailable values are shown as “—”, with no assumptions made.

Model	Brightness	Resolution
EIKI EK-800U	—	—

To verify whether a model outside the list is compatible, send us photos of the projector nameplate and existing lens—projectors from the same generation often share a mount, but ordering based on a similar model is not worth the risk.

Throw Ratio by Model Series

The nominal throw ratio differs by series when the same AH-B22020 Zoom is installed on the following series. Use the value corresponding to the actual projector series when selecting a lens.

Model Series	Throw Ratio
—	1.02-1.36:1

4. Three Checks Before Replacement

• Confirm the projector chip and resolution. The original lens is designed for a specific panel size. If the panel specifications differ, the image circle cannot cover the full image, resulting in vignetting or edge light loss.
• Calculate the installation distance first. This lens has a nominal throw ratio of 1.02-1.36:1; use the table in Section 2 to calculate the distance for your venue. A fixed-focus lens offers no adjustment margin, while a zoom lens should also allow an extra 10–20 cm at both ends.
• Verify the mount and locking mechanism. The original lens is calibrated to the mount of that model series and must be heard to lock securely after installation. A skewed image and soft edges are usually caused by incomplete locking, not by a problem with the lens itself.

If you are unsure, take one photo of each nameplate—the projector and the existing lens—and send them to us. Verification against the actual hardware is the safest approach.