SC226 Projector Lens 0.85–1.37:1 for 2 Hualu Models, Including HL-GU18K and GU21K

SC226 is a short-throw lens for 0.96-inch panels (Hualu), with a 0.85–1.37:1 throw ratio and lens shift. It is compatible with 2 projector models across 1 model series. This article presents the lens specifications, installation distance, model compatibility list, and replacement considerations in one place.

I. Lens Specifications

Lens shift is the key differentiator of this lens. A shift range of 10% horizontal and 4% vertical allows the projector to be installed off the screen’s central axis, with lens shift used to reposition the image without requiring keystone correction. Keystone correction comes at a cost—each correction step sacrifices some effective pixels and blurs text edges. In professional installations, never use keystone correction when lens shift can solve the alignment; preserving image quality is non-negotiable.

II. Calculating Installation Distance from the Throw Ratio

The throw ratio is the ratio of the installation distance to the image width. This is a zoom lens (0.85–1.37:1), so each image size corresponds to a range of installation distances, and the lens can be focused at any position within that range.

The distances above are clear distances from the front lens surface to the screen and do not account for clearance for rear cooling and cabling. They are calculated for a 16:10 image aspect ratio; actual values are subject to on-site measurements and the manual.

Image quality varies at the two ends of the zoom range: near the shorter end, the image is brighter and the edges are slightly softer; near the longer end, the edges are sharper and the brightness is slightly lower. When the venue allows, the middle of the range is recommended. After installation, first find the sharpest position on the focus ring, then fine-tune the shift—adjusting both variables at the same time makes precise alignment difficult.

III. Compatible Models (2 Models, Hualu)

The table below is arranged from newest to oldest by model production date and includes each model’s resolution, brightness, and zoom ratio of the original lens, making it easy to identify the right option for project requirements.

The zoom ratio is the zoom factor of the model’s original standard lens (upper limit ÷ lower limit of the original throw ratio range), not the zoom range of the lens featured in this article.

Common Features of These Models

The original standard lenses for these 2 models generally have throw ratios concentrated around 1.5~2.0. The 0.85–1.37:1 ratio of the model in this article effectively adjusts the focal range, allowing different image sizes at the same projection distance—this is precisely the direct reason for replacing the lens. At the same time, full lens shift capability is retained, so the image can still be aligned after the focal range is changed.

IV. Three Checks Before Replacement

• The panel and resolution must match. This model is compatible with a 0.96-inch panel. Projectors with different panel sizes or resolutions will vary somewhat in projection performance; the safest approach is to verify the specifications against the chassis nameplate before installation.
• Interfaces and locking mechanism. Interfaces on platforms of the same generation generally offer good compatibility, but locking latch positions vary by generation. If the image appears skewed or the edges are soft after installation, the lock is usually not fully engaged rather than the lens itself being defective.
• Factor the shift margin into the installation. The shift range provides some installation leeway, but edge image quality declines at the extremes. It is recommended to keep actual use within 70% of the rated values.

For compatibility with a model not on the list, the safest approach is to send us the chassis nameplate and a photo of the original lens for verification—same-generation platforms often share the same interfaces, but placing an order based only on a similar model designation is not worth the risk.