Optoma BX-CTA19 Wide Zoom Standard Throw Lens: Fits WU1500 ZU1700 ZU1900 ZU2200

Optoma Original Lens BX-CTA19 Wide Zoom is an original optical accessory for Optoma professional projectors. It is a standard-throw lens (Standard Throw) with a throw ratio of 1.02-1.36:1. The official model compatibility list covers 4 models. Before installation, simply verify the projector model and panel size; there is no need to make do with adapter rings. The value of an original lens lies not in the additional specifications listed in its datasheet, but in the fact that it is calibrated at the factory to the optical path and lens mount of that model series. Once installed, the image circle, edge illumination, and focusing travel all meet their design values, so there is no need to compensate for image quality with keystone correction.

I. Lens Specifications

The above specifications are subject to the manufacturer's official specifications. For mechanical dimensions, flange distance, and lens-mount type not shown in the specification table, please contact us with the projector model. Placing an order solely because the model numbers appear similar risks a fit that may not work.

II. Converting Throw Ratio into Installation Distance

The throw ratio is the ratio of the installation distance to the image width. This original lens is a zoom lens (1.02-1.36:1), so a given image size corresponds to a range of distances, and the lens can focus at any distance within that range during installation.

The above figures represent the clear distance from the front surface of the lens to the projection screen and do not include space behind the projector for ventilation and cable connections. They are calculated for a 16:10 aspect ratio; actual distances should be verified on site and in accordance with the manufacturer's manual.

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

III. Compatible Projector Models (4 models)

The table below is taken from the official model compatibility list. Brightness and resolution are populated from the model database; unavailable data is shown as “—” and is not estimated.

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

Throw Ratios by Projector Model Series

The rated throw ratio of the same BX-CTA19 Wide Zoom varies by the series listed below. For model selection, use the value corresponding to the series of the actual projector.

IV. Three Checks Before Replacement

• Confirm the projector's imaging chip and resolution. Original lenses are 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 after installation.
• Calculate the installation distance first. This lens has a rated throw ratio of 1.02-1.36:1; use the table in Section II to calculate the distance for your installation space. Fixed-focus lenses offer no adjustment margin, and zoom lenses should also allow an additional 10–20 cm at both ends.
• Verify the lens mount and locking mechanism. The original lens is calibrated to the mount of that model series and must audibly lock into place after installation. A skewed image or soft edges are usually caused by the lens not being fully locked, rather than by a fault in the lens itself.

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