Digital Projection SL-4K-121 Standard Throw Projector Lens: INSIGHT 4K Laser, INSIGHT Laser 8K

Digital Projection Original Lens SL-4K-121 is a genuine optical accessory for Digital Projection large-venue projectors. It belongs to the standard throw category, with a throw ratio of 0.93:1 (fixed focal length), designed for 0.95inch 3DLP(INSIGHT) panels. The original compatibility list covers 3 projector models; simply verify against the projector model and panel size before installation—no adapter rings needed. The value of an original lens isn't about extra rows of numbers in a spec sheet, but that it is calibrated at the factory to the optical path and bayonet of that projector series: once mounted, the image circle, edge illumination, and focus travel all match design values, so you don't need keystone correction to compensate for image quality.

1. Lens Specifications

Brand	Digital Projection (Digital Projection)
Lens Model	SL-4K-121
Original Part Number	115-630
Throw Ratio	0.93:1 (fixed focal length)
Product Type	Standard Throw
Compatible Panel	0.95inch 3DLP(INSIGHT)
Compatible Models	3 units
Warranty	12 months; non-human damage covered by after-sales service, based on the date on the shipping document

The above specifications are subject to the original manufacturer's specifications. For mechanical dimensions, flange focal distance, and bayonet type not shown in the spec table, please verify with us against your projector model—ordering based on model similarity alone carries the risk of incompatibility.

2. Throw Ratio Conversion for Installation Distance

Throw ratio is the ratio of installation distance to image width. This original lens is fixed focal length (0.93:1 (fixed focal length)), so the installation distance changes linearly with image size with no adjustment margin—measure precisely before installation.

Image Size	Image Width	Required Installation Distance
100 inch	2.15 m	approx. 2.00 m
120 inch	2.58 m	approx. 2.40 m
150 inch	3.22 m	approx. 3.00 m
200 inch	4.30 m	approx. 4.00 m

The above figures are the clear distance from the lens front to the screen, excluding rear ventilation and cabling space behind the projector. Calculated for 16:10 aspect ratio; actual values are subject to on-site measurement and the original manufacturer's manual.

3. Compatible Models (3 units)

The table below is taken from the original compatibility list; brightness and resolution are filled in from the model database, with "—" where unavailable—no speculation.

Model	Brightness	Resolution
INSIGHT 4K Laser	—	—
INSIGHT Laser 8K	—	—
INSIGHT MLS	—	—

To check whether models outside the list are compatible, please send us photos of the projector nameplate and the existing lens for verification—same-generation platforms often share bayonets, but the risk of ordering based on model similarity alone isn't worth it.

Throw Ratios Across Model Series

The same SL-4K-121 mounted on the following series has different nominal throw ratios; selection must use the value for the actual projector series.

Model Series	Throw Ratio
—	0.93:1 (fixed focal length)

4. Three Things to Confirm Before Replacement

• Panel size must match. The SL-4K-121 is designed for 0.95inch 3DLP(INSIGHT) panels. Projectors with different panel sizes or resolutions may have image circle and edge illumination issues even if the bayonet fits.
• Calculate installation distance first. This lens has a nominal throw ratio of 0.93:1 (fixed focal length); apply it to your venue dimensions using the table in Section 2. Fixed focal length has no margin; even for zoom lenses, leave 10–20 cm at both ends.
• Check the bayonet and locking. The original lens is calibrated to the bayonet of that projector series; after mounting, you must hear it lock into place. Image skew and soft edges are usually due to incomplete locking, not the lens itself.

If unsure, take a photo of the projector nameplate and the existing lens nameplate and send them to us—verification against the actual hardware is the safest approach.