The Ezer ETN-1800 non-contact tonometer is a fully automated, table-top air-puff instrument with a published measurement range of 1–60 mmHg, fully automated 3D tracking alignment, a motorized chinrest and a built-in thermal printer. It is built around a single operational premise: that taking an intraocular pressure reading should be a task a trained technician can complete without joystick hunting, and without the doctor in the room.
This is a single-model deep dive. If you are still deciding which non-contact tonometer belongs in your practice, start with our 2026 non-contact tonometer buyer's guide, which compares the category across brands. This page assumes that decision is made and answers the next question: what exactly does this instrument do, what does its spec sheet leave out, and what should you confirm in writing before you sign. For the clinical rationale behind IOP measurement itself, see our companion article on how glaucoma is diagnosed — this page stays on the equipment decision.
Shopping for non-contact tonometers? US Ophthalmic is a direct provider of non-contact tonometers to eye care practices across the US. Tell us how your lane is set up and we will come back with the configurations that fit, plus current availability and lead times.
Published specifications
Every figure below is taken directly from the current ETN-1800 product page. Where the manufacturer does not publish a specification, we say so rather than estimate it, and we list those gaps as questions to ask.
| Measurement principle | Air puff method |
| Measurement range | 1–60 mmHg |
| Measurement range setting | Auto / 30 mmHg / 60 mmHg |
| Display units | mmHg / hPa |
| Working distance | 11 mm |
| Alignment | Fully automated 3D tracking |
| Chinrest | Motorized |
| Printer | Thermal line printer with auto-cut function |
| Interface | USB / RS232 |
| Power supply | AC 100–240 V, 50/60 Hz, auto selected |
| Operating environment | Temperature 10 °C to 35 °C; humidity 30% to 90% |
| Dimensions (W×D×H) | 12×20×20 in (282×500×500 mm) |
| Weight | 38 lb (17 kg) |
What "fully automated 3D tracking" actually changes
Automation is the specification that most changes how this instrument fits into a working practice, and it is the one buyers most often skim past.
On a manually aligned tonometer, the operator drives a joystick in three axes to bring the instrument into position on each eye before firing. That is a learned motor skill. It is the reason tonometry on older instruments tends to stay with whoever happens to be good at it, and the reason a new hire's first weeks produce more repeat attempts than anyone budgets for.
The ETN-1800 removes that skill requirement entirely. The alignment specification is fully automated 3D tracking, and the chinrest is motorized rather than hand-cranked. Between them, the two mean the operator's job is reduced to seating the patient, entering or selecting the record, and confirming the capture. That is what makes the instrument delegable.
The practical consequences are worth spelling out, because they are what you are actually buying:
- Training time collapses. There is no joystick technique to teach, so a new technician's competence is a matter of understanding the workflow rather than developing a physical skill.
- Results stop depending on who is working. When alignment is instrument-driven rather than operator-driven, the variable of "which staff member ran it" is largely removed from the process.
- The bottleneck moves. Once capture is automatic, your pre-test throughput is limited by patient seating and data entry, not by the instrument. That is worth knowing before you buy a second unit to solve a queue that a second chair would fix.
The trade-off is the one every motorized instrument carries: there are more moving parts than on a manual unit. The motorized chinrest in particular is a mechanical assembly under daily cycling. This is exactly the kind of component where an in-house parts and service department matters more than the purchase decision, and we come back to it below.
The three range settings: what is published, and what to ask
Against its full published range of 1–60 mmHg, the ETN-1800 offers a range setting selectable between Auto, 30 mmHg and 60 mmHg. Buyers frequently read this as three levels of accuracy. It is not that — but the published specification stops at naming the three options and does not describe what the instrument does differently in each, so we are not going to guess on your behalf. Ask your equipment specialist to walk your staff through all three at installation, and to state which one ships as the default.
Treat it as a defaults question to settle once, with your team present, rather than a per-patient decision at the chinrest. Which setting is clinically appropriate for a given patient is a matter for the practitioner, not the equipment specification; if you are weighing how IOP measurement fits into your wider protocol, that belongs with your glaucoma workup, not your purchase order.
Working distance, footprint and the table it needs
The 11 mm working distance is the gap the instrument maintains between the nozzle and the eye at capture. It matters for one reason buyers care about: it is the physical distance that makes an air-puff instrument a non-contact instrument. Nothing touches the eye, so there is no probe to disinfect between patients and no tip inventory to manage.
The numbers that get overlooked are the ones on the bottom of the spec table, and they are the ones that decide whether the instrument fits your lane:
- Footprint: 282 mm wide by 500 mm deep (about 12 by 20 inches). The depth is the number to check, not the width. Half a meter of table depth plus room for the patient's chin and the operator's screen access is more than some pre-test counters actually have.
- Height: 500 mm (about 20 inches). Add this to your table height and confirm the eyepiece lands in a seated patient's range — the motorized chinrest travels, but the table does not.
- Weight: 17 kg (38 lb). Well within a proper instrument table's capacity, but worth confirming against a shared or older table that is already carrying another unit.
- Power: AC 100–240 V, 50/60 Hz, auto selected. The auto-selecting supply means the same unit works on any standard US outlet without configuration, and travels to a satellite office or a second site without a transformer.
- Operating environment: 10 °C to 35 °C, 30% to 90% humidity. Comfortable for any conditioned exam room. Worth a second look if the instrument will live in a mobile unit, an unconditioned satellite office, or a room that loses climate control over a weekend.
Getting data out: USB, RS232 and the printer
The ETN-1800's stated interfaces are USB and RS232, and the manufacturer describes the instrument as connectable to patient records, with on-board display, search and input so staff can look up and edit patient data at the instrument. The built-in thermal printer has an auto-cut function and can be set to print automatically after every use.
This is the section of the spec sheet where we would push you hardest to ask a follow-up question, because "USB / RS232" describes a physical connector, not an integration.
Ask specifically what the connection delivers in your environment. A serial or USB link can mean a true bidirectional interface into your EHR, or a one-way export of results, or a file drop that someone still has to attach to the chart. Those are three very different amounts of daily staff time, and they are not distinguishable from a spec table. Before you buy, ask your equipment specialist to confirm — in writing, naming your specific EHR — what the ETN-1800 will do in your practice. RS232 in particular is a legacy serial standard, so if you are planning an integration, also ask what adapter or interface box is required on a current workstation.
Budget for the paper. A thermal line printer with auto-cut is a genuine workflow convenience, and it is also a consumable. Thermal roll size and sourcing is a small recurring line item that nobody puts in the capital budget and everybody discovers in month two. Confirm the roll specification at purchase and order a starting supply with the instrument.
Where the ETN-1800 sits in our tonometer line-up
US Ophthalmic carries tonometers in three physical formats — table-top, slit-lamp mounted and handheld — and the format, not the brand, is usually the real decision. The table below compares the ETN-1800 with the closest carried unit in each of the two table-mounted formats, using what each manufacturer publishes. It is a fit-and-format comparison, not a clinical one.
| Instrument | Format | Published range | Weight |
| Ezer ETN-1800 | Table-top, non-contact (air puff) | 1–60 mmHg | 17 kg |
| Frey TN-100 | Table-top, non-contact (air puff) | 0–60 mmHg | 18 kg |
| Ezer ESL-Emerald-TN | Slit-lamp mounted applanation | 0–80 mmHg | 725 g |
Against the Frey TN-100, the closest carried comparison, the two are near-identical in physical class — both are roughly 300 mm-wide, ~500 mm-deep table-top instruments in the 17–18 kg range, both fully automated, both with an electrically adjusted chinrest, a built-in thermal printer and a 100–240 V supply. The differences worth knowing are in what each manufacturer chooses to publish. The TN-100 publishes a stated measurement accuracy of 0.5 mmHg, a 7-inch color LCD, internal flash plus SD card storage, and a database capacity of up to 4,000 patients with XML as the data format. The ETN-1800's published table does not state an accuracy figure, a screen size or a storage capacity. That is a documentation difference rather than a performance verdict — but if on-board patient database capacity or a specific export format is load-bearing for your workflow, the TN-100 tells you the answer up front and the ETN-1800 is a question to put to your equipment specialist.
Against the slit-lamp mounted ESL-Emerald-TN, the comparison is not really competitive — it is a different place in the exam. At 725 g and mounted to the slit lamp, that unit lives in the doctor's chair-side workflow; the ETN-1800 lives in pre-test and is designed to be run before the patient reaches the doctor. Practices commonly run both. You can see the mounted options in slit-lamp tonometers and the full air-puff line in non-contact tonometers.
What the spec sheet does not answer — confirm these before you buy
These are genuine gaps in the published ETN-1800 specification. None of them is a red flag; all of them are answerable by asking, and all of them are easier to resolve before a purchase order than after.
- Measurement accuracy. Not stated in the published table. Request the manufacturer's figure.
- Corneal thickness handling. The published specification lists no pachymeter. If a central corneal thickness value is part of your protocol, ask whether the software accepts a manually entered CCT and what it does with it.
- Screen size and on-board storage. The description references a large touch screen and patient look-up, but the spec table gives no dimension or record capacity. Ask for both.
- Export format. Ask what file or message format leaves the instrument, and confirm it against your EHR by name.
- Thermal roll specification. Get the exact roll size and a source, and order spares with the unit.
- Warranty term and what it covers. Specifically ask whether the motorized chinrest assembly and the printer mechanism are covered, since those are the moving parts.
- Parts availability and typical turnaround. Ask how long a repair actually takes and whether parts are held domestically.
Buying the ETN-1800 from US Ophthalmic
Ezer is US Ophthalmic's own brand, which changes the ownership picture in a way that is easy to underrate when you are comparing spec tables.
Because the line is ours, support does not route through a chain of third parties. US Ophthalmic is a direct provider to eye care practices nationwide, with an in-house technical and spare-parts department and US-based warranty and service. On an instrument whose defining features are a motorized chinrest, a tracking alignment system and a printer mechanism — three assemblies with moving parts that will cycle every working day for years — who answers the phone in year four is a real part of the total cost of ownership, not a footnote to it. You can read more about how we support the equipment we sell, and if you are building a lane from scratch, our new practice equipment checklist puts the tonometer in context alongside everything else you will need.
Ready to spec your non-contact tonometers?
Send us your requirements and our equipment specialists will come back with a configuration built around how your practice actually works — including availability and lead time. US Ophthalmic is a direct provider to eye care practices nationwide.
Frequently asked questions
What is the measurement range of the Ezer ETN-1800?
The published measurement range is 1–60 mmHg, with a selectable range setting of Auto, 30 mmHg or 60 mmHg. Results can be displayed in mmHg or hPa.
How does the ETN-1800 measure intraocular pressure?
By the air puff method, at an 11 mm working distance. Nothing contacts the eye, so there is no probe tip to disinfect or replace between patients.
Does the ETN-1800 need a skilled operator?
Alignment is specified as fully automated 3D tracking and the chinrest is motorized, so there is no joystick alignment technique to learn. The operator seats the patient, handles the record and confirms the capture, which makes the instrument straightforward to delegate to trained staff.
How much space does the ETN-1800 need?
It measures 282×500×500 mm (roughly 12×20×20 inches) and weighs 17 kg (38 lb). The 500 mm depth is usually the constraint — check your table depth before ordering.
Can the ETN-1800 connect to our patient records?
The instrument provides USB and RS232 interfaces and on-board patient display, search and entry. Because those are connector standards rather than a defined integration, confirm with your equipment specialist what the connection will deliver with your specific EHR before you buy.
Does it print results?
Yes. It has a built-in thermal line printer with an auto-cut function, and it can be configured to print automatically after each use. Thermal rolls are an ongoing consumable to budget for.
Will it run on standard US power?
Yes. The supply is AC 100–240 V, 50/60 Hz and auto-selecting, so it works on any standard outlet and moves between sites without a transformer.
How does the ETN-1800 compare with the Frey TN-100?
Both are fully automated table-top non-contact tonometers of very similar size, weight and power class, each with a motorized chinrest and built-in thermal printer. The TN-100 additionally publishes a stated accuracy of 0.5 mmHg, a 7-inch LCD, SD-card storage and XML export; the ETN-1800's published table does not list those figures. If on-board database capacity or a named export format is critical to your workflow, ask for the ETN-1800's figures before deciding.
What warranty and service come with it?
Ezer is US Ophthalmic's own brand, supported by an in-house technical and spare-parts department with US-based warranty and service. Confirm the specific term and whether the motorized chinrest and printer assemblies are included when you request your quote.
