Engineering essay
A tablet on a door is a computer that wants power, brightness, and a lock screen. An e-ink register is a still frame that should survive a weekend. We do not sell either door. This page exists so you do not confuse a chest badge with a corridor computer.
Engineering essay. No public display SKU. No hire. No buy. No checkout. Calendar pairing is specified, not live. If you need a door panel this week, buy from a shop that lists one.
Tablets run applications. They play video, take taps like a phone, and die when Facilities forgets the charger. They are familiar. They are also a glowing rectangle in a glass corridor at 08:00 in February.
E-ink doors hold pigment. They refresh when written. Between writes they look like paper. They are slow compared with 60 Hz glass. That slowness is the point if the job is a status sentence, not a browser.
A 250×122 three-ink badge is neither. It is a chest film. Do not put it on a door with blu-tack and call it a room display. Handshake distance is not corridor distance. Brick red is not sixteen greys.
Joan 6 RE (6 September 2026) is a 6-inch touch e-paper at 1024×758, roughly three months of battery in their published story, magnetic mount, €349 plus licence. That is the comparison class for doors. Our comparison class for chests is their 4-inch four-colour badge, on a different URL.
LCD doors need a PSU in the wall or a ritual. The ritual fails on bank holidays. PoE tablets exist; they are still computers with a backlight. Budget the electrician.
E-ink’s published month-scale batteries assume a write rate, not a video loop. If you push a new image every ten seconds, you have bought a radio with extra guilt. EcoSync-style honesty (Joan’s term on their site) is a policy: write when the calendar actually changed.
USB-C on our badges is a chest-device charge, not a door story. Do not infer a wall panel from a hire crate that includes a cable.
If your building forbids batteries in corridors, you are in a different RFP: mains or PoE. That constraint picks the shop. We still have no SKU to offer inside it.
A tablet competes with a window. Facilities turns brightness up. Battery dies. The lock screen appears. The door now says swipe. Occupancy truth died for a password.
E-ink pigment does not emit. Side light still matters — a recessed mount in a dark niche can look muddy — but you are not fighting a specular backlight in the same way.
Colour: tablets show photographs of rooms. Grey e-ink shows a timetable. Four-colour visitor badges (Joan’s 528×768 shop panel) are a third object. Do not mix colour counts in one sentence.
Accessibility: contrast on grey e-ink is a design problem. Tiny type on 6-inch grey fails older eyes. Large room name, then time. Applications that cram a week view onto 6 inches fail both technologies.
An iPad on a VESA arm is a known street price. Staff will notice when it vanishes. Insurance will ask why the door ran a consumer tablet.
E-ink panels are less liquid on a second-hand market, which is not the same as secure. Magnetic mounts can still walk. Specify a screw and a policy.
Lock screens on tablets are a security feature that destroy the corridor job. If the door requires Face ID, you have built a kiosk, not a status register.
Our hire badges in a foam crate are a different theft model: they leave in a van with a return label. A door SKU would need asset tags. We do not have that SKU.
Sleep on LCD is a lie: the panel looks off, then a tap wakes a browser that might still show yesterday. Occupancy truth is a write, not a dimmer.
E-ink can also lie: a ghost image from a failed write, or a radio that did not wake. Honesty is firmware plus calendar health, not the word paper.
Touch on Joan 6 RE exists because they sell workplace verbs. A non-touch status poster can still work if the calendar is the only writer. Buttons are optional. Truth is not.
Video, wayfinding maps, and ads are tablet jobs. Putting them on e-ink is a category error. If you need a map, buy a map. If you need a room sentence, buy a register — from a shop that has one.
LCD does not burn like 1998 CRTs in every panel, but a static room name on a cheap tablet still ages. E-ink ghosts when a write is incomplete. Both technologies lie. Honesty is a write policy plus a refresh when the calendar moved.
A still frame is the e-ink bet. If you need a wayfinding map that pans, you wanted a tablet. Putting a map on grey e-paper is a category error we will not sell.
Joan 6 RE’s sixteen greys are a timetable palette. Our badge’s three inks are a chest palette. Neither is a photograph of the room. Tablets show photographs. Pick the job.
Burn-in arguments in RFPs often come from signage CMS vendors. Occupancy truth does not need a playlist. If you bought a CMS, you are not in this essay’s problem.
February, glazed corridor, 08:00. The tablet is a mirror. Brightness goes up. Battery dies before lunch. The lock screen appears. The door now says swipe. Occupancy truth died for a password.
Facilities learns this the second winter. PoE exists. It needs an electrician. Budget that if you insist on glass.
E-ink pigment does not emit. A recessed niche can still look muddy. Specify light, or specify a front-lit panel from a shop that has one. Joan lists a front light on 6 RE. We list nothing, because we sell nothing here.
USB-C on our badges is a chest-device fact. Do not order a crate and expect a wall wart for a door you imagined.
A tablet kiosk can run a browser, take a signature, play an induction video. That is a glass job. Envoy and the kiosk cohort live there. We do not.
A status register answers two questions without unlocking a phone. Applications that cram a week view onto six inches fail both LCD and e-ink. Large room name, then time.
Touch on Joan 6 RE exists because they sell Meet now. Non-touch posters can still work if the calendar is the only writer. Buttons are optional. Truth is not.
Lock screens are a security feature that destroy the corridor job. If the door requires Face ID, you built a kiosk. Score it as a kiosk.
Chest film: 250×122, three inks, hire or buy, Cleckheaton compile. Corridor film: someone else’s millimetres, someone else’s licence, someone else’s mount — until we publish ours.
Do not blu-tack a name badge to a door. Handshake distance is not walking distance. Brick red is not sixteen greys.
If you run Joan on doors and hire us for Thursday’s visitors, you have sequenced vendors correctly. Mixing jobs in one trial is how you score SSO against a box of bezels.
This page still has no cart. The parent essay repeats the notice. The badge pillar takes payment because the object ships.
A person who just booked on their phone may wait seconds before the door agrees. That is acceptable if the image is then still. It is not acceptable if the image lies for an hour because the radio slept and nobody wrote a policy.
LCD sleep looks like a dead room. Black glass in a corridor is ambiguous: off, free, or broken. E-ink’s still pigment at least looks like a sign. Ghosting is a different lie. Name both.
Video, ads, and animated wayfinding are tablet jobs. If the brief includes those, stop reading this essay and buy glass. If the brief is a sentence about the next hour, you wanted a register — from a vendor who lists one.
Measured watt-hours beat slogans. If you have a logger on a tablet door, email the number. We will not invent a three-month figure for a panel we do not sell, and we will not pretend our badge cell is a wall panel.
Theft, glare, power, and sleep are the four reasons people replace tablet doors. E-ink answers three of them if the write rate is honest. Refresh latency is the remaining tax. None of those sentences is a SKU. The live SKU is the chest at handshake height, hired or bought from Cleckheaton, not a corridor computer taped to a screw plate on a Tuesday morning in February.
This page does not hire a tablet. It does not hire an e-ink door. It does not route to /book/ as if a display were in the crate.
Read /e-ink-displays/ for the parent notice, /e-ink-displays/room-status/ for calendar verbs we do not ship, and /e-ink-badges/ for the object we do ship.
If a future door SKU exists, the versus-tablets argument will sit next to a price. Until then, Joan’s shop and other integrators are the live hardware path for corridors.
Corrections to tablet-versus-e-ink claims: hire@inkbadgehire.com. Bring a measured watt-hour if you have one. We will not invent a three-month number for a panel we do not sell.
This URL does not take payment for a door. Joan 6 RE public facts are dated 6 September 2026: getjoan.com/joan-6-re/. Badge hire and buy live on the chest pillar.