Optoma
ZK431ST-B
The brightest true-4K ultra-short-throw we carry under $2,000, and one of the few projectors in the catalog that Optoma builds specifically for simulator use — it ships with a Golf Sim Lens and a factory-calibrated Golf Sim colour mode rather than a generic preset you tune yourself. 4,100 ANSI lumens of native 4K at a 0.496:1 throw, which puts a 100-inch image up from under three feet. The DuraCore laser is rated 30,000 hours in eco mode, half again the life of BenQ's laser line. Input lag is published and low: 16.7 ms at 4K/60 and 8.6 ms at 1080p/120. Against the UHZ35ST at $1,499 it is $300 more for 600 extra lumens at the same throw and the same resolution. That is the whole decision — if your room controls light well, the cheaper unit is enough.
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Who this is for
Honest match per persona.
Good for
- Performance Seeker
Native 4K with published low lag and a factory golf colour profile, so the image is right without a calibration session. 4,100 lumens holds up in a room that is not fully blacked out.
- Space-Constrained
0.496:1 puts a 100-inch image up from under three feet, so it mounts close and stays out of the swing path. The tightest throw in the catalog alongside the GT2400HDR, but in 4K.
- Family Setup
Bright enough for a room with ambient light and fast enough to game on, which is what a shared room actually gets used for between rounds.
Not for
- Cost-Effective Buyer
$1,799 when the UHZ35ST is 4K at the same throw for $1,499. The 600 extra lumens are real but they are not a value argument.
- Recreational Player
Fixed throw with no zoom means placement is decided for you. A zoom model is more forgiving if you are not building around it.
- Showroom
Mid-tier brightness. The ZK521ST-B or the LK936ST are what a showroom room wants.
Specifications
The numbers, plainly stated.
Image
| Resolution | 4K UHD (3840×2160) native |
| Lumens | 4,100 ANSI |
| Picture Mode | Golf Sim colour mode, factory-calibrated |
| Screen Size | 30–300 in |
Hardware
| Light Source | DuraCore laser (30,000 hours, eco) |
| Throw Ratio | 0.496:1 (ultra-short throw) |
| Lens | Golf Sim short-throw lens included |
| Keystone | ±15° with Smart Fit auto-alignment |
Performance
| Input Lag | 16.7 ms at 4K/60Hz; 8.6 ms at 1080p/120Hz |
Builds that include this product
Where this fits in a full simulator.
Same category, different tradeoff
Other projectors we considered.
Mid-tierBenQAH500ST0.499 throw, 4,000 lumens, golf-dedicated. The right answer when ceiling depth is the constraint.
Mid-tierBenQTK700STiTrue 4K with HDR — the cheaper 4K option vs. the laser TK710STi. Still a community favorite when budget caps at $1,500.
Mid-tierOptomaUHZ35ST4K + laser + 4.4ms input lag at $1,499. The fastest 4K sim/gaming projector under $1,500.
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