Ricoh 308935 Fixed #1 Short-Throw Lens for PJ WU6181N PJ WX6181N PJ X6180N

Genuine Ricoh Lens 308935 Fixed #1 is an OEM optical accessory for Ricoh professional projectors. It is a short-throw (Short Throw) lens with a throw ratio of 0.80:1. The OEM compatibility list covers 3 models; before installation, simply verify the projector model and panel size, with no need to make do with adapter rings. The value of an OEM lens lies not in a few extra rows of figures, but in its factory calibration to the optical path and mount of the relevant model series: once installed, the image circle, edge illumination, and focusing travel are all at their design values, eliminating the need to use keystone correction to compensate for image quality.

I. Lens Specifications

The above specifications are based on the OEM specifications. Mechanical dimensions, flange distance, and mount type are not shown in the specifications table and should be verified with us according to the projector model. Placing an order solely because the model numbers are similar carries the risk that the lens will not fit.

II. Calculating Installation Distance from Throw Ratio

The throw ratio is the ratio of the installation distance to the image width. This genuine lens has a fixed focal length (0.80:1), so the installation distance varies linearly with image size and offers no adjustment margin. It must be measured accurately before installation.

These figures represent the clear distance from the front face of the lens to the screen and do not allow for rear projector ventilation or cable connection space. They are calculated for a 16:10 image; actual values are subject to on-site measurement and the manufacturer's manual.

III. Compatible Models (3 Models)

The table below is taken from the OEM compatibility list. Brightness and resolution are populated from the projector model database; entries that cannot be obtained are marked “—” and are not estimated.

To verify whether a model not on the list can use this lens, send us photos of the projector nameplate and the existing lens—projector platforms of the same generation often share a mount, but ordering on the basis of a similar model is not worth the risk.

Throw Ratio by Model Series

The nominal throw ratio differs by model series when the same 308935 Fixed #1 is installed. Select the value based on 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 area, causing vignetting or light loss at the edges after installation.
• Calculate the installation distance first. This lens has a nominal throw ratio of 0.80:1; use the table in Section II to calculate the distance for your site dimensions. A fixed-focal-length lens offers no adjustment margin, and even a zoom lens should have 10–20 cm of clearance at both ends.
• Verify the mount and lock. The OEM lens is calibrated to the mount of that model series and must audibly lock into place after installation. A skewed image or soft edges is usually due to an incompletely engaged lock, 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 equipment is the most reliable approach.