Projector Room-Fit Guide · Short throw 4K laser
BenQ LH820ST for a Golf Simulator: Throw Distance & Mounting Guide
BenQ · 3840x2160 · 4000 lumens · Updated June 2026
The BenQ LH820ST has a 0.81–0.89 throw ratio, which means it needs 11′ 6″ to 12′ 8″ of distance to fill a standard 8-foot-tall 16:9 impact screen. That short throw is what makes it sim-friendly: the projector mounts ahead of the hitting area, so your body never blocks the beam.
Throw distance by screen size
Lens-to-screen distance for common impact-screen heights (16:9 aspect).
| Screen height (16:9) | Image width | Lens-to-screen distance |
|---|---|---|
| 7 ft | 12.4 ft | 10′ 1″ – 11′ 1″ |
| 7.5 ft | 13.3 ft | 10′ 10″ – 11′ 10″ |
| 8 ft | 14.2 ft | 11′ 6″ – 12′ 8″ |
| 8.5 ft | 15.1 ft | 12′ 3″ – 13′ 5″ |
| 9 ft | 16.0 ft | 13′ 0″ – 14′ 3″ |
Ceiling mount & lens drop
With a 108% vertical offset, in a 9 ft room a 7.5 ft screen would push the lens above the ceiling — lower the screen or use a model with lens shift; in a 10 ft room with a 8 ft screen the lens sits about 4″ below the ceiling. Match your ceiling mount's drop length to that number — fixed 6″ drop mounts are often too long for high-offset short throws, which hangs the image below the screen.
Room depth check
Budget about 18 ft of total room depth for the BenQ LH820ST: maximum throw of 12′ 8″ to an 8 ft screen, plus 10–12 ft of ball-to-screen distance and swing room (throw and hitting space overlap with a short throw, which is why it fits tighter rooms). Behind-ball radar launch monitors add a further 7–9 ft behind the ball.
Frequently asked questions
How far should the BenQ LH820ST be from a golf simulator screen?
For an 8 ft tall 16:9 impact screen (14.2 ft wide), the BenQ LH820ST's 0.81–0.89 throw ratio puts the lens 11′ 6″ to 12′ 8″ from the screen. Measure from the front of the lens, not the back of the chassis.
Is the BenQ LH820ST good for a golf simulator?
BenQ LH820ST is a short throw 4k laser model with 4000 lumens. Its short throw keeps the mount ahead of the golfer, which minimizes shadows on the screen.
What room depth do I need for the BenQ LH820ST?
Plan on roughly 18 ft minimum: 12′ 8″ of throw to an 8 ft screen plus ball-flight and stance space. Radar launch monitors push the comfortable minimum higher — verify your exact layout in the free calculator.
Similar projectors
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- Optoma UHD35STx — Short throw 4K gaming, 0.50–0.50 throw
- Optoma EH200ST — Short throw 1080p business, 0.49–0.66 throw
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