The Quick Verdict
Get the Optoma ZK431ST-B. It lists at $2,699 against the BenQ's $4,899 MSRP, a $2,200 gap at list. It puts up a wider image from the same mounting distance, and Optoma states a 4:3 mode, which matters if your impact screen is 4:3. The BenQ LK936ST 4K HDR Short Throw Laser Projector is worth its list price only if you want a golf mode the maker actually names, or the mounting slack of optical zoom and lens shift. The Optoma's fixed lens offers neither. Check price at The Indoor Golf Shop →
What They Have in Common
Both are laser projectors at 3840x2160 with a 16:9 native shape, and both are short-throw. Each lists 16.7 ms of input lag at 1080p 60Hz, so there's no gap there. Neither BenQ nor Optoma publishes a warranty term for these models, so ask about that before you commit to either one.
Where They Differ
Throw and image size
Image width = throw distance ÷ throw ratio. The BenQ's zoom lens runs 0.81–0.89:1, so from 10 ft back it puts up an image 11.2 ft to 12.3 ft wide. The Optoma's fixed lens is 0.496:1, which gives an image 20.2 ft wide from the same 10 ft. For a 10 ft wide image, the BenQ sits 8.1 ft–8.9 ft from the screen and the Optoma sits 5.0 ft from it.
That's the practical split. For the same size image, the Optoma hangs closer to the screen and the BenQ hangs further from it. Where the projector hangs decides what's between the lens and the screen, and in a hitting bay that includes you. Measure the distance from where the lens would sit to the screen, then check it against those figures.
Screen shapes and mounting slack
Optoma states 4:3, 16:9 and 16:10 modes. A square 1:1 isn't among them. BenQ lists no selectable modes for the LK936ST at all. That isn't the same as saying it only does 16:9; BenQ just doesn't say.
On adjustment, BenQ gives the LK936ST 1.1x optical zoom, vertical lens shift of -60%+60%, horizontal shift of -23%+23%, and 3D keystone at ±40 degrees vertical, horizontal and rotation. The Optoma has a fixed lens with no lens shift, a stated offset of 114%, and keystone of ±15° horizontal and vertical. Zoom and shift give you some room to land the image without moving the mount. With the Optoma, the mount position has to be right.
Brightness, golf mode and light source
BenQ lists 5,100 lumens without stating a measurement standard. Optoma lists 4,100 lumens to ISO 21118. Those figures aren't measured the same way, so I won't call either one brighter.
BenQ names a golf mode on the LK936ST. Optoma doesn't say whether the ZK431ST-B has one, and that means unpublished, not "no." BenQ rates the laser at 20,000 hours. Optoma publishes no light-source life figure.
Size, year and price
The Optoma weighs 6.3 lbs at 10.8 W x 4.3 H x 8.5 D inches. The BenQ weighs 15.4 lbs at 16.4 x 6.5 x 13.8 inches, which makes it 9.1 lbs heavier. The BenQ is a 2021 release and the Optoma is a 2026 model. At list, it's $4,899 for the BenQ and $2,699 for the Optoma.
Who Should Buy Which
Get the Optoma ZK431ST-B if:
- Your impact screen is 4:3. Optoma states that mode, and BenQ lists no modes.
- The projector needs to hang close to the screen: 5.0 ft out for a 10 ft wide image.
- You want the lower list price: $2,699, which is $2,200 under the BenQ.
- You're mounting overhead and want the lighter unit at 6.3 lbs.
Get the BenQ LK936ST 4K HDR Short Throw Laser Projector if:
- You want a golf picture mode the maker names.
- You can't lock in the mount position exactly and want 1.1x zoom plus lens shift to make up the difference.
- You want a published light-source rating, which BenQ puts at 20,000 hours.
- The lens can sit 8.1 ft–8.9 ft from the screen for a 10 ft wide image.
If your screen is square, neither maker states a 1:1 mode, so that won't settle it.
The Bottom Line
The Optoma ZK431ST-B lists $2,200 under the BenQ, gets a 10 ft wide image from 5.0 ft out, states a 4:3 mode and weighs 6.3 lbs. The BenQ LK936ST 4K HDR Short Throw Laser Projector brings zoom, lens shift, wider keystone, a named golf mode and a published 20,000-hour laser rating. That's the whole case for paying $4,899. Call it a hunch, but in a hitting bay a stated 4:3 mode and $2,200 at list count for more than mounting slack. Measure lens-to-screen first.