Optoma BX-CTA22 Long Zoom Lens for WU1500 ZK1000 ZK1050 ZK1120 ZK1320 ZK750 ZU1700 ZU1900 ZU2200

Optoma Original Lens BX-CTA22 Long Zoom is an original optical accessory for Optoma business projectors. It is a long-throw (Long Throw) lens with a throw ratio of 2.00-4.00:1. The manufacturer's compatibility list covers 9 models, so simply verify the projector model and panel size before installation—no need for an adapter-ring workaround. The value of an original lens lies not in the extra figures on a specification sheet, but in the fact that it is factory-calibrated 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, eliminating the need to use keystone correction to compensate for image quality.

1. Lens Specifications

Brand	Optoma (Optoma)
Lens Model	BX-CTA22 Long Zoom
Throw Ratio	2.00-4.00:1
Product Type	Long Throw
Compatible Models	9 Models
Warranty	12 months; after-sales service applies to damage not caused by the user, subject to the date on the shipping document.

The above specifications are subject to the manufacturer's official specifications. For mechanical dimensions, flange distance, and mount type not listed in the specifications table, please provide your projector model so we can verify them. Placing an order solely because the model is similar carries the risk that the lens will not fit.

2. Calculating Installation Distance from Throw Ratio

The throw ratio is the ratio of the installation distance to the image width. This original zoom lens (2.00-4.00:1) provides a range of installation distances for each image size, and it can focus at any distance within that range during installation.

Image Size	Image Width	Required Installation Distance
100 inches	2.15 m	Approx. 4.30 – 8.60 m
120 inches	2.58 m	Approx. 5.16 – 10.32 m
150 inches	3.22 m	Approx. 6.45 – 12.90 m
200 inches	4.30 m	Approx. 8.60 – 17.20 m

The above is the clear distance from the front face of the lens to the projection screen and does not include space behind the projector for ventilation and cable connections. These distances are calculated for a 16:10 image; actual distances should be confirmed through on-site measurements and the manufacturer's manual.

Image quality varies 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 the image is slightly dimmer. Where the installation environment allows, use the middle of the range. After installation, find the sharpest setting on the focus ring, then fine-tune the lens shift.

3. Compatible Models (9 Models)

The table below is taken from the manufacturer's compatibility list. Brightness and resolution are populated from the model database; where the data is unavailable, an em dash (—) is shown rather than estimated.

Projector Model	Brightness	Resolution
WU1500	11000 lumens	1920x1200
ZK1000	10000 lumens	3840x2400
ZK1050	11000 lumens	4K (3840 x 2160)
ZK1120	11500 lumens	4K (3840 x 2160)
ZK1320	13500 lumens	4K (3840 x 2160)
ZK750	7500 lumens	4K (3840 x 2160)
ZU1700	17000 lumens	WUXGA,1920 x 1200
ZU1900	19000 lumens	WUXGA,1920 x 1200
ZU2200	25000 lumens	WUXGA,1920 x 1200

For models not on the list, send us photos of the projector nameplate and the existing lens so we can verify compatibility. Platforms from the same generation often share the same mount, but ordering based solely on a similar model name carries unnecessary risk.

Throw Ratio by Model Series

The specified throw ratio varies by model series when the same BX-CTA22 Long Zoom lens is installed. Select the value that applies to the series of your projector.

Model Series	Throw Ratio
—	2.00-4.00:1

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 panel, resulting in vignetting or edge light loss after installation.
• Calculate the installation distance first.This lens has a specified throw ratio of 2.00-4.00:1. Use the table in Section 2 to calculate the distance for your installation space. A fixed-focus lens offers no adjustment margin, and even a zoom lens requires an additional 10–20 cm at both ends.
• Verify the mount and locking mechanism.The original lens is calibrated to the mount used on that model series, and you must hear it lock into place 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, send us one photo each of the projector nameplate and the nameplate on the existing lens. Verification against the actual hardware is the most reliable approach.