Vivitek D98-4070 Ultra Long Zoom Telephoto Lens: DU9900Z-BK Compatibility

Vivitek Genuine Lens D98-4070 Ultra Long Zoom is a factory-supplied optical accessory for Vivitek engineering projectors. It is a long-throw lens (Long Throw) with a throw ratio of 4.00-7.00:1 for the inch-size panels used in the DU/DW/DX engineering series. The manufacturer's compatibility list covers 1 model; before installation, simply verify the projector model and panel size—no adapter-ring workaround is needed. The value of a genuine lens lies not in the extra figures in a specification sheet, but in the fact that it is calibrated at the factory to the optical path and mount of that projector series. Once installed, the image circle, edge illumination, and focus 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. Mechanical dimensions, flange distance, and mount type are not listed in the specification table. Please verify them with us based on your projector model; ordering solely because the model numbers are similar risks a fitment failure.

II. Calculating Installation Distance from Throw Ratio

The throw ratio is the ratio of installation distance to image width. This genuine lens is a zoom lens (4.00-7.00:1), so a given image size corresponds to a range of installation distances; it can focus anywhere within that range.

These figures represent the clear distance from the front of the lens to the screen and do not include space behind the projector for cooling and cable connections. They are calculated for a 16:10 aspect ratio; actual values should be verified through on-site measurements and in accordance with 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 long end, the edges are sharper and brightness is slightly lower. When the venue allows, the middle of the range is recommended. After installation, find the sharpest position on the focus ring first, then fine-tune the lens shift.

III. Compatible Models (1 model)

The table below is taken from the manufacturer's compatibility list. Brightness and resolution are populated from the model database; entries that cannot be obtained are shown as "—" and are not estimated.

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

Throw Ratio by Model Series

The rated throw ratio varies by series when the same D98-4070 Ultra Long Zoom lens is used on the models listed below. Use the value corresponding to the actual projector's series when selecting.

IV. Three Checks Before Replacement

• Panel size must match. D98-4070 Ultra Long Zoom is designed for the inch-size panels in the DU/DW/DX engineering series. Even if the mount fits, a projector with a different panel size or resolution will have problems with the image circle and edge illumination.
• Calculate installation distance first. The rated throw ratio of this lens is 4.00-7.00:1. Use the table in Section II to calculate the distance for your venue; a fixed-focus lens has no adjustment margin, and even a zoom lens should allow 10–20 cm at both ends of the range.
• Check the mount and locking mechanism. The genuine lens is calibrated for the mount of this projector series. After installation, you must hear the lock engage; a skewed image or soft edges is usually caused by incomplete locking, not by a fault in the lens itself.

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