Screens and projection · HUB · REV 2026-10-06
Screens and projection
The image is an engineering decision: what must be read, from what distance, under what light, and how the panel is serviced or the lamp replaced. A handsome render is not a viewing distance and not a cooling load.
What this gate is
The gate compares an LED screen with a projector from viewer geometry, not from which technology is newer. Pixel pitch is discussed with the one-arcminute estimate: distance in metres is about 3.4 times pitch in millimetres when a pixel subtends 1/60 of a degree. That is an acuity estimate, not a product rule.
Luminance comes from the manufacturer sheet at the stated drive and content, not from this gate. Indoor and outdoor are different problems because daylight is far above hall lighting. AVIXA DISCAS is a procedure for 2D image size. This gate does not perform it and does not output a screen height.
What is published now
LED screens
Pitch versus distance, indoor versus outdoor, front or rear service, power, heat, and content.
Projectors
Throw ratio, ambient light, screen gain, lamp versus laser as maintenance, and short-throw shadow.
What stays with the standard
DISCAS for image size, the lens table for actual image width, and the panel sheet for any nit value.
Coordination with the hall
Sightline, stage lighting, exhibition-stand viewing distance, and electrical power and cooling load.
When to open this gate
Before room depth is frozen
Throw needs distance. A wall needs width and service access. Both change the architectural section if the decision is late.
When the content changes
Fine text and drawings sit closer to the viewer than scenic video at the same distance. Pitch and throw follow the task.
When the light is not a studio
Windows, house light, or a bright exhibition stand. Contrast is a room problem, not a lumen figure invented here.
How to read the subject
- 01
Name the farthest viewer, the nearest viewer, and the task: reading text, following a face, or a general image. Without those three there is no image size.
- 02
Treat the one-arcminute estimate as a geometric limit for when a pixel shows, not as a brand minimum distance. Content, luminance, and acuity move the figure.
- 03
Ask about service before the facade: a rear catwalk, front removal, or a lamp and lens change that does not mean dismantling half the ceiling.
- 04
Turn content into electrical and thermal load from the manufacturer sheet. Full white is not a meeting video, and the sheet is what names the difference.
What this gate does not do
A nit value from this gate
No luminance on this gate may be copied as a BoxTech O2mea specification. An indoor room is not designed with an outdoor figure.
A throw ratio with no lens table
Distance over width is a class name. Actual image width comes from the lens table at the shift in use.
Performing DISCAS by guesswork
The standard exists and ties image height to the farthest viewer and the content class. This gate does not run the calculation.
Questions designers and owners ask
Is a finer pitch always better?
Only if the viewer is close enough to resolve the pixel and the content is worth the cost and the heat. From far away, the finer pitch is not read.
Does laser remove throw geometry?
No. Laser is a maintenance and source-life choice against a lamp. Short-throw shadow, screen gain, and ambient light remain room decisions.
Where do I take luminance?
From the panel or projector sheet at the stated content and drive. Not from a page on this site.
Does a screen fix a bad sightline?
No. If the head in front blocks the image, a larger screen can make it worse. The sightline is solved in section.
What do I open after the gate?
The LED page or the projector page, then the matching calculator as a first guess, then the manufacturer sheet and the standard.
Technical sources
- AVIXA DISCAS
The procedure for 2D content image size from viewing task and distance. This gate does not perform the procedure.
- Panel or projector manufacturer sheet
Pitch, luminance, power, and the lens table. Copy them with their conditions, not as a detached marketing figure.
- One-arcminute geometry
An angle of 1/60 of a degree gives about 3.4 m of distance per millimetre of pitch. An acuity estimate, not a product rule.
Last editorial review: 2026-10-06. Review means the text was checked, not that a project was measured.
Turn the question into a brief
A study starts from room volume, use, and existing condition, not from a product name. Fill the brief and copy it.
Project study form