BenQ 5J.JAM37.051 Semi Long Zoom Lens: Compatible with 9 Models

BenQ Genuine Lens 5J.JAM37.051 Semi Long Zoom is an OEM optical accessory for BenQ professional projectors. It is a long-throw (Long Throw) lens with a throw ratio of 2.22:1 - 3.67:1. The factory model compatibility list covers 9 projector models. Before installation, simply verify the projector model and panel size; there is no need to improvise with an adapter ring. The value of an OEM lens lies not in the extra rows in the specification table, but in the fact that it is calibrated at the factory to the optical path and mount of the corresponding model series: once installed, the image circle, edge illumination, and focusing travel are all at their design values, so there is no need to use keystone correction to compensate for image quality.

I. Lens Specifications

The above specifications are subject to the manufacturer's official 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.

II. Calculating Installation Distance from the Throw Ratio

The throw ratio is the ratio of the installation distance to the image width. This OEM lens is a zoom lens (2.22:1 - 3.67:1), so each image size corresponds to a range of distances, and it can focus at any point within that range when installed.

The values above represent the clear distance from the front surface of the lens to the screen and do not include the space behind the projector required for cooling and cable connections. They are calculated for a 16:10 image; in practice, use on-site measurements and the manufacturer's manual.

Image quality differs at the two ends of the zoom range: near the short-throw end, the image is brighter and the edges are slightly softer; near the long-throw end, the edges are sharper and brightness decreases slightly. If the installation site allows, positioning the lens around the middle of the range is recommended. After installation, first find the sharpest setting on the focus ring, then fine-tune the lens shift.

III. Compatible Projector Models (9 Models)

The table below is taken from the manufacturer's model compatibility list. Brightness and resolution are filled in from the model database; where the data is unavailable, “—” is shown, and no values are estimated.

For models not on the list, send us photos of the projector nameplate and the existing lens so we can verify compatibility. Although platforms of the same generation often share a mount, the risk of ordering based solely on a similar model is not worth taking.

Throw Ratio by Model Series

The rated throw ratio of the same 5J.JAM37.051 Semi Long Zoom lens varies by model series. When selecting a lens, use the value for the series of the actual projector.

IV. Three Checks Before Replacement

• Confirm the projector's imaging chip and resolution.OEM 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 light loss at the edges.
• Calculate the installation distance first.The rated throw ratio of this lens is 2.22:1 - 3.67:1. Use the table in Section II to calculate the distance for your site dimensions. A fixed-focus lens provides no adjustment margin, and even a zoom lens requires 10–20 cm of leeway at both ends.
• Check the mount and locking mechanism.OEM lenses are calibrated to the mount of the corresponding projector series, and you must hear the lens click into the locked position after installation. A skewed image or soft edges is usually caused by incomplete locking, rather than a problem with the lens itself.

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