Christie 118-131106-03 ILS1 Fixed UST Lens: M 4K+15 RGB, M 4K+25 RGB, M 4K15 RGB, M 4K25 RGB

Christie Original Lens 118-131106-03 ILS1 Fixed is an OEM optical accessory for Christie engineering projectors, in the ultra short throw (Ultra Short Throw) category, with a throw ratio of 0.37:1. The factory compatibility list covers 4 models; before installation, simply verify the chassis model and panel size — no need to make do with adapter rings. The value of an original lens lies not in the extra rows of numbers in the spec sheet, but in the fact that it is calibrated at the factory to the optical path and mount of that chassis series: the image circle, edge illumination and focus travel are all at their design values once fitted, so there is no need to compensate for picture quality with keystone correction.

1. Lens Specifications

Brand	Christie (Christie)
Lens Model	118-131106-03 ILS1 Fixed
Throw Ratio	0.37:1
Product Type	Ultra Short Throw (Ultra Short Throw)
Compatible Models	4 models
Warranty	12 months; for damage other than human-induced causes, after-sales service applies, based on the date shown on the shipping document

The above specifications are subject to the original factory specifications. For mechanical dimensions, flange distance and mount type not shown in the spec table, please verify with us by chassis model — ordering directly on the basis of a similar model number carries the risk that the lens will not fit.

2. Converting Throw Ratio into Installation Distance

The throw ratio is the ratio of the installation distance to the image width. This original lens is a fixed-focus lens (0.37:1): the installation distance varies linearly with image size, with no adjustment margin, so it must be measured accurately before installation.

Image Size	Image Width	Required Installation Distance
100 inches	2.15 m	approx. 0.80 m
120 inches	2.58 m	approx. 0.95 m
150 inches	3.22 m	approx. 1.19 m
200 inches	4.30 m	approx. 1.59 m

The above is the clear distance from the front of the lens to the screen, without accounting for the space required for heat dissipation and cabling at the rear of the chassis. Calculated for a 16:10 aspect ratio; actual results are subject to on-site measurement and the original manufacturer's manual.

3. Compatible Models (4 models)

The table below is taken from the original factory compatibility list; brightness and resolution are backfilled from the model database, and entries that cannot be retrieved are marked "—"; no assumptions are made.

Model	Brightness	Resolution
M 4K+15 RGB	—	—
M 4K+25 RGB	—	—
M 4K15 RGB	—	—
M 4K25 RGB	—	—

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

Throw Ratios for Different Model Series

The nominal throw ratio of the same 118-131106-03 ILS1 Fixed differs across the series listed below, so select the value according to the series of the actual chassis.

Model Series	Throw Ratio
—	0.37:1

4. Three Things to Confirm Before Replacement

• Confirm the chassis chipset and resolution. The original lens is designed for a specific panel size; when the panel specification differs, the image circle cannot cover the full area, resulting in vignetting or edge light loss once the lens is fitted.
• Calculate the installation distance first. This lens has a nominal throw ratio of 0.37:1, so apply the table in Section 2 to your own venue dimensions; a fixed-focus lens has no margin, and even a zoom lens needs 10–20 cm of reserve at both ends.
• Check the mount and locking mechanism. The original lens is calibrated to the mount of that chassis series, and you must hear it lock into place after installation; a skewed image or soft edges are usually caused by the lock not being fully engaged, not by the lens itself.

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