NEC NP31ZL Zoom Standard Throw Lens: Fits 10 Models incl. PX1004UL-B-18, PX1004UL-BK, PX700W2

The NEC original lens NP31ZL Zoom is an OEM optical accessory for NEC professional projectors. It is a standard-throw lens (Standard Throw), with a throw ratio of 0.75-0.93:1. The factory compatibility list covers 10 projector models; before installation, simply verify the projector model and panel size—there is no need to make do with an adapter ring. The value of an original lens lies not in the extra numbers in the specification sheet, but in the fact that it is calibrated at the factory to the optical path and mount of the relevant projector 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.

1. 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 specification table, please verify them with us using the projector model; placing an order solely on the basis of a similar model carries the risk that the lens will not fit.

2. Throw Ratio and Installation Distance

The throw ratio is the ratio of installation distance to image width. This original lens is a zoom lens (0.75-0.93:1), so the same image size corresponds to a range of distances; installation anywhere within this range allows the lens to focus.

The distances above are clear distances from the front face of the lens to the screen and do not include space required for rear cooling and cable connections on the projector. They are calculated for a 16:10 image; actual values should be confirmed by on-site measurement and 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 is slightly lower. When site conditions allow, it is recommended to position the lens near the middle of the range. After installation, first find the sharpest position on the focus ring, then fine-tune the lens shift.

3. Compatible Projector Models (10 Models)

The table below is taken from the factory compatibility list; brightness and resolution are populated from the model database, and unavailable values are shown as “—”, with no assumptions made.

To determine whether a model outside the list can be used, please send us photos of the projector nameplate and the existing lens for verification—platforms from the same generation often share the same mount, but ordering based on a similar model is not worth the risk.

Throw Ratio by Model Series

The rated throw ratio varies by projector series when the same NP31ZL Zoom is used; use the value corresponding to the series of the actual projector when selecting a lens.

4. Three Checks Before Replacement

• Confirm the projector's imaging chip and resolution. Original lenses are designed for specific panel sizes; 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 0.75-0.93:1; use the table in Section 2 to calculate the distance for your site dimensions. A fixed-focus lens has no adjustment margin, while a zoom lens should also allow 10–20 cm at both ends.
• Verify the mount and locking mechanism. The original lens is calibrated to the mount of that projector series; after installation, you must hear it lock into place. Image skew and soft edges are usually due to incomplete locking, not a problem with 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; checking against the actual equipment is the safest approach.