HOLOCUBIC — TINY 'HOLOGRAPHIC' CUBE DISPLAY ON ESP32 (6.7K STARS)
A coin-sized ESP32 board projects a floating image inside a transparent cube using a beam-splitter prism and a 240×240 screen.
DisplaysOpen-hardware
- difficulty
- ●●●●○
- time
- a weekend-plus
- license
- GPL-3.0
- repo
- repo ACTIVE6,677 stars
●●●●○ · a weekend-plus · GPL-3.0 · 6,677 stars · repo ACTIVE
WHAT YOU’LL NEED
- 3D printer + filament — printable parts — files are in the repo
- Electronic parts — full list with part numbers in the repo BOM
- Dev board / microcontroller — runs the project firmware
Partner
COMPAREE VERDICT
HoloCubic is a desktop curiosity that uses a beam-splitter prism to reflect a tiny LCD into the centre of a clear cube, creating the illusion of a floating image. An MPU6050 IMU lets you control it by tilting — no buttons. The effect is striking in person, but this is not a hologram in the physics sense; it is a mirror trick, and the viewing angle is narrow. The project became famous because the creator built it in a single weekend and posted a polished video, but replicating that timeline assumes you already know how to order PCBs with SMT assembly, source Chinese components from the BOM, and debug PlatformIO firmware. The repo has everything you need to manufacture the boards and print the enclosure, but the documentation is thin and mostly in Chinese. The single biggest trap is the prism: the STL files include a holder, but the prism itself is glass or acrylic and you have to source it separately — the repo does not give a size or a link. If you have never ordered a custom PCB or soldered 0402 components, this will be a frustrating first project. If you have, and you want a tiny desk ornament that surprises people, this is a well-executed build with a strong visual payoff.
IN THE REPO
NOT IN THE REPO
- —Two PCB designs (v1 and v2, Altium and KiCad sources), full firmware (PlatformIO), and STL files for the cube and prism holder are all in the repo.
- —The BOM is a spreadsheet in Chinese with part numbers but no supplier links or current prices.
- —There is no English build guide. The README is brief, the wiki pages are mostly in Chinese, and assembly assumes you know how to order PCBs and source SMT components.
- —The licence is GPL-3.0, which permits commercial use but requires derivative works to remain open source under the same licence.
- —The beam-splitter prism is not 3D printed — you buy or cut a glass/acrylic pyramid separately, and the repo does not specify a size or supplier.
Can I build this?
Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.
Partner · KickstarterHeyGears G1: 10M+ colors and transparent parts in one print, plus UV printing on flat objects. Figures, parts and labels — no painting.
Videos
Creator demo video (Chinese, no subtitles)
This is the original video by Zhihui Peng that made the project famous — excellent production quality, shows the build and the effect in action, but there is no voiceover build guide and no English subtitles.
Gallery
Start here
Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.
- 1.Read the README and check the wiki (The wiki has some assembly notes, but most pages are in Chinese. Use a browser translator.)
- 2.Review the BOM and source the prism(The BOM spreadsheet is in the repo under /hardware. The beam-splitter prism is not listed — search for 'holographic pyramid prism' or measure and cut one from acrylic sheet.)
- 3.Order the PCB with assembly(Export Gerbers from the KiCad or Altium files (v2 is recommended), upload to JLCPCB or PCBWay, and use their SMT assembly service with the provided BOM and CPL files. Hand-solder the through-hole parts when it arrives.)
- 4.Compile and flash the firmware(The firmware is in /software, built with PlatformIO. You will need to install the ESP32 toolchain and any library dependencies listed in platformio.ini.)
Resources
Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.
Partner · KickstarterBluHub reads and burns Blu-ray/DVD/CD, adds USB-C, USB-A, SD/TF and 10 Gbps data — plug and play, grand-piano finish.
KNOWN ISSUES
- The beam-splitter prism is not in the BOM and the repo does not link to a supplier or give exact dimensions. Most builders buy a 'holographic display pyramid' from AliExpress or eBay and trim it to fit, or laser-cut one from 2mm acrylic. Measure twice.
- The BOM is a Chinese-language spreadsheet with LCSC part numbers but no English descriptions and no indication of which parts are critical vs. substitutable. If you have never cross-referenced datasheets, budget time for this.
- The PCB has 0402 passives and a QFN ESP32 module. Unless you pay for SMT assembly, hand-soldering this is expert-level work. Most people use a PCB fab's assembly service and solder only the battery connector and a few headers.
- There is no step-by-step build guide in English. The README is a feature list, the wiki has fragments, and the rest is reverse-engineering the KiCad files and the firmware. Expect to spend as much time researching as building.
- The tilt control is sensitive and the firmware's default settings may feel twitchy. Tuning the IMU thresholds requires editing and reflashing the code.
- The 1.54-inch ST7789 display is not a standard Adafruit part — verify the pinout and driver IC before ordering, because there are multiple incompatible modules sold under similar names.
Is this an actual hologram?
No. It is a beam-splitter illusion — a mirror pyramid reflects the LCD image so it appears to float in the centre of the cube. The effect only works from certain angles, and there is no 3D depth. It is the same principle used in Pepper's Ghost stage tricks.
Can I buy a kit with all the parts?
There is no official kit. Some sellers on AliExpress and Tindie offer unofficial HoloCubic clones or part bundles, but quality varies and they may use older PCB revisions. Sourcing the parts yourself from the repo BOM gives you the most control.
Do I need to know Chinese to build this?
It helps. The BOM, most of the wiki, and the original video are in Chinese. Browser translation works for the text, but part numbers and firmware comments are easier if you can read some technical Chinese or are comfortable cross-referencing datasheets in English.
How long does the battery last?
The README does not specify, and it depends on which LiPo you use and how bright you run the display. Community reports suggest a few hours of continuous use with a 500mAh cell.
Can I use a different microcontroller?
The firmware is tightly coupled to the ESP32-PICO-D4 and the ST7789 driver. Porting to another chip would mean rewriting the display and IMU code. Possible, but not a weekend project.
Community builds
No community builds yet — be the first, we feature the best ones.
Discussion1
FROM THE COMPAREE TEAM
The repo has two PCB versions and the creator built it in a weekend — but there is no English build guide and the prism is not in the BOM. If you have built this, where did you source the pyramid and how long did assembly actually take?
Zhihui Peng (稚晖君)
Zhihui Peng is a hardware engineer and maker known for highly polished open-source electronics projects. HoloCubic was built in a single weekend as a desktop curiosity and posted with a cinematic video, which went viral in the Chinese maker community and brought the project to 6.7k GitHub stars.
Keep building — related projects
Same category, picked by how close they are to this build.
FULL CADSmartKnob — open-source haptic input knob with software-defined detents
Open-hardwareDisplays●●●●○advanced
FULL CADBuild your own e-paper smartwatch for 60 dollars — the battery lasts a week
Open-hardwareDisplays●●●○○moderate
Partner · KickstarterCORE POWER BANK S: 0.2" thin, 2.8 oz, 5000 mAh with 22.5W fast charging. Semi-solid battery, carbon fiber, IPX7 waterproof.
FULL CADBuild your own e-paper smartwatch for 60 dollars — the battery lasts a week
Open-hardwareDisplays●●●○○moderate
FULL CADYou can build a cinema camera that records the same RAW format as the professional ones
Open-hardwareDisplays●●●●○advanced
DISCLAIMER
- Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
- Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
- Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
CompareeTEAM1mo agoedited
Practical notes from our verification: the repo has been stable since 2021 with occasional minor firmware updates, the KiCad files are complete and recent PCB fabs handle them without issues, and the single largest time sink is not the build — it is sourcing the beam-splitter prism, which is mentioned nowhere in the README and has no specified dimensions. Most community builders buy a generic 'holographic display pyramid' from AliExpress (search for 3-4cm base width) and file it to fit, or laser-cut one from 2mm clear acrylic using the holder STL as a sizing guide. The effect in person is narrower and dimmer than the video suggests, but it is genuinely striking on a desk. If you have never ordered SMT assembly, the PCB will feel expensive for what is essentially a novelty — but the design is clean and the firmware is stable once flashed.