Eiki AH-A25010 Short Fixed Lens for EK-623U EK-623UW EK-625U EK-815U EK-820U

Eiki original lens AH-A25010 Short Fixed is an original optical accessory for Eiki engineering projectors. It is an ultra-short-throw (Ultra Short Throw) lens with a throw ratio of 0.36:1. The factory compatibility list covers 5 models; before installation, simply verify the projector model and panel size, with no need for adapter rings. The value of an original lens lies not in the extra specifications it adds to a datasheet, but in the fact that it is calibrated at the factory to the optical path and mount of that model series. Once installed, the image circle, edge illumination, and focus travel all meet their design values, with no need to use keystone correction to compensate for image quality.

1. Lens Specifications

These specifications are subject to the original manufacturer's specifications. For mechanical dimensions, flange distance, and mount type not listed above, please check with us using the projector model. Ordering based solely on a similar model carries the risk that the lens will not fit.

2. Calculating Installation Distance from the Throw Ratio

The throw ratio is the ratio of the installation distance to the image width. This original lens is a fixed lens (0.36:1), so the installation distance varies linearly with image size, with no adjustment range. Accurate measurements are essential before installation.

The values above represent the clear distance from the front surface of the lens to the screen and do not allow for ventilation clearance or cable connections behind the projector. They are calculated for a 16:10 image; confirm the actual distances through on-site measurement and in accordance with the manufacturer's manual.

3. Compatible Models (5 Projectors)

The following table is taken from the manufacturer's compatibility list. Brightness and resolution have been populated from the model database; entries that could not be verified are shown as “—” and have not been estimated.

To determine whether a model outside the list can be used, send us photos of the projector nameplate and the existing lens for verification. Models from the same generation often share the same mount, but ordering based on a similar model is not worth the risk.

Throw Ratios by Model Series

The nominal throw ratio of the same AH-A25010 Short Fixed lens varies across the series listed below. When selecting a lens, use the value for the actual projector series.

4. Three Checks Before Replacement

• Confirm the projector imaging chip and resolution. The original lens is designed for a specific panel size. If the panel specifications differ, the image circle cannot provide full coverage, resulting in vignetting or light falloff at the edges after installation.
• Calculate the installation distance first. This lens has a rated throw ratio of 0.36:1. Use the table in Section 2 to calculate the required distance for your site. A fixed lens offers no adjustment margin, and even zoom lenses need 10–20 cm of clearance at both ends.
• Verify the mount and locking mechanism. The original lens is calibrated to the mount of that model series. After installation, you must hear it lock into place. A skewed image or poorly defined edges usually indicate that the lens is not fully locked, rather than a fault with the lens itself.

If you are unsure, photograph both the projector nameplate and the nameplate on the existing lens and send the photos to us. Verification against the actual hardware is the safest approach.