Optoma BX-DL100 Zoom Standard-Throw Lens for EH503 EH503e EH505 EH505-B EH505e W505 X605

Optoma Genuine Lens BX-DL100 Zoom is an OEM optical accessory for Optoma business projectors. It is a standard-throw lens (Standard Throw) with a throw ratio of 1.15-1.37:1. The official compatibility list covers 7 models; before installation, simply verify the projector model and panel size—no need to make do with an adapter ring. The value of a genuine lens lies not in the extra figures in the specification sheet, but in the fact that it is calibrated at the factory to the optical path and lens mount of the corresponding projector 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.

I. Lens Specifications

The above specifications are subject to the official specifications. For mechanical dimensions, flange distance, and mount type not listed in the specification table, please contact us with the projector model for verification. Ordering based solely on a similar model carries the risk that the lens will not fit.

II. Calculating Installation Distance from the Throw Ratio

The throw ratio is the ratio of the installation distance to the image width. This genuine lens is a zoom lens (1.15-1.37:1), so each image size corresponds to a range of installation distances. The lens can achieve focus at any distance within that range during installation.

These distances represent the clear distance from the front face of the lens to the screen and do not account for ventilation or cable connection clearance behind the projector. They are calculated for a 16:10 image; actual distances should be verified through on-site measurements and in accordance with the official manual.

Image quality differs at the two ends of the zoom range: the image is brighter and the edges slightly softer near the short-throw end, while the edges are sharper and brightness is slightly lower near the long-throw end. Where the venue allows, it is recommended to position the lens near the middle of the range. After installation, first find the sharpest position using the focus ring, and then fine-tune the lens shift.

III. Compatible Models (7 Models)

The table below is taken from the official compatibility list. Brightness and resolution have been populated from the model database; unavailable information is marked as “—” and has not been estimated.

To determine whether a model outside the list is compatible, send us photographs of the projector nameplate and the existing lens for verification. Platforms from the same generation often share the same mount, but it is not worth taking the risk of ordering based solely on a similar model number.

Throw Ratios by Model Series

The rated throw ratio of the same BX-DL100 Zoom varies depending on the series below. When selecting a lens, use the value corresponding to the series of the actual projector.

IV. Three Checks Before Replacement

• Confirm the projector panel and resolution.OEM lenses are designed for specific panel sizes. If the panel specifications differ, the image circle cannot cover the full image, resulting in vignetting or light loss at the edges after installation.
• Calculate the installation distance first.This lens has a rated throw ratio of 1.15-1.37:1. Use the table in Section 2 to calculate the distance for your venue dimensions. Fixed-focus lenses provide no margin, and zoom lenses still require an additional 10–20 cm at both ends of the range.
• Verify the lens mount and locking mechanism.The OEM lens is calibrated to the lens mount of the corresponding projector series and must audibly click into the locked position after installation. A skewed image or soft edges are usually caused by incomplete locking rather than a problem with the lens itself.

If you are unsure, take one photograph of the projector nameplate and one of the existing lens nameplate and send them to us. Verification against the actual equipment is the most reliable approach.