Projection Mapping Glossary: 28 Terms from Lumens, Edge Blending and Media Servers to Outdoor Advertising Rules

Projection mapping is a form of expression where terms from many fields meet: not only video production, but also projector and audio equipment, venue permissions and safety standards. This glossary briefly defines 28 terms that are easy to stumble over when reading articles, project proposals or local government calls for proposals, grouped into four sections: basics, equipment, production, and operations and regulations. Links to TOKYO ART SPHERE’s explainers are included for readers who want to learn more.

Basic terms

Projection mapping

A technique in which video created to fit the shape of a building or object is projected onto it, making the object appear to move or transform. Its defining feature is that the three-dimensional form itself, rather than a flat screen, becomes the stage for the images. How it works and its history are explained in our article on what projection mapping is.

Immersive exhibition

An exhibition that surrounds visitors with images and sound on the walls and floor, letting them experience the work as if stepping into its world. Some venues use rows of projectors, while others display images on LED screens. See also our article on what immersive art is.

Media art

Artworks that use technologies such as computers, sensors and networks, and incorporate the characteristics of those media into their expression. Projection mapping can be seen as one of its forms. Its history is introduced in our media art explainer.

Nighttime economy

Economic activity at night. Many local governments use the illumination and projection mapping of cultural properties and government buildings as highlights of nighttime tourism. Examples are summarized in our article on the nighttime economy and light art.

Light-up and illumination

Light-up usually refers to lighting buildings or trees with floodlights, and illumination to decorations made by arranging light bulbs or LEDs. Both differ in technique from projection mapping, which projects video.

Equipment terms

Projector

A device that projects video as light. To project onto large outdoor buildings, several high-brightness professional projectors are often combined.

Lumen (lm)

A unit of the amount of light (luminous flux), used as a measure of a projector’s brightness. The higher the number, the brighter the projector. The brightness required depends on the darkness of the surroundings, the size and color of the projection surface, and the viewing distance.

Resolution (4K, WUXGA)

The number of pixels that make up an image. Standard 4K is 3,840 × 2,160 pixels, and WUXGA is 1,920 × 1,200 pixels. Combining the images of several projectors creates a picture larger and more detailed than one projector can produce.

DLP and 3LCD

Two different ways projectors create images. DLP controls light with a chip covered in tiny mirrors (DMD), while 3LCD uses three liquid-crystal panels for red, green and blue. Large professional models also use 3-chip DLP with three DMDs.

Laser light source

A projector that uses lasers as its light source. Compared with lamp-based models, it is said to last longer and lose less brightness over time, and it is widely used in permanent venues. Technology trends are introduced in our article on projectors and laser light sources.

Throw ratio and short-throw lens

Throw ratio is the projection distance divided by the image width. The smaller the number, the larger the image a projector can create from a short distance. In venues with limited space for equipment, short-throw lenses are used. Installation basics are summarized in our projector installation guide.

Media server

Hardware or software that distributes video to multiple projectors and plays it back in sync. It also handles geometric correction and blending, and synchronization with sound and lighting.

Edge blending

A process that overlaps the edges of images from multiple projectors and gradually changes the brightness of the overlap so that the seams are less visible.

Geometric correction (warping)

A process that distorts the image to match the shape and angle of the projection surface so that it appears as intended. It is essential when projecting onto curved or angled surfaces. The flow from measurement to projection is explained in our article on how projection mapping works.

Spatial audio

Sound that uses many speakers to express the position and movement of sounds within a space. Some technologies change what visitors hear depending on where they stand, and spatial audio is used in immersive exhibitions. Case studies are introduced in our article on the projectors and sound systems behind immersive exhibitions.

Production terms

3D measurement (3D scanning) and point clouds

The process of turning the shape of a building or object into data with laser scanners or photogrammetry. The collection of points obtained is called a point cloud and becomes the foundation for video production.

3DCG

Three-dimensional computer graphics. Creating images to match a 3D model of a building makes it possible to produce illusions such as walls collapsing or popping out.

Content production

Creating the video, music and sound effects to be projected. Local government calls for proposals often group planning and the production of images and sound together as “content production.”

Test projection

The process of actually projecting on site before the show to check brightness, position, appearance and the effect of light on the surroundings. Sometimes images are tested on a scale model. The flow from planning to the show is introduced in our article on how to stage projection mapping.

Loop and scheduled screenings

A loop screening repeats the same video with breaks in between, while a scheduled screening runs at fixed times. The length of screenings and the intervals between them also affect crowd management in viewing areas.

Operations and regulations

Permission from the facility manager

Projecting onto a building requires permission from its owner or manager. For National Treasures, Important Cultural Properties and similar buildings, equipment installation and projection methods are coordinated with the owner or manager and the authorities in charge of cultural properties. The approach is summarized in our article on projection mapping on cultural properties.

Outdoor advertising ordinance

A local government ordinance that regulates outdoor advertising. If the projected images include advertising elements such as company names or logos, permission may be required. For details, see our article on projection mapping and outdoor advertising rules.

Road use permit

A permit from the chief of the local police station may be required when equipment is placed on a road or an event is held on a road.

Light pollution

The negative effects of outdoor lighting and other light on residents’ lives, ecosystems and the visibility of the night sky. Japan’s Ministry of the Environment has issued guidelines on light pollution. See also our article on the light pollution guidelines.

Flicker standards

Strong flashing light and flashing saturated red can trigger photosensitive seizures. Tokyo’s guidelines ask that, as a rule, flashing not exceed three times per second.

Proposal-based competition

One way local governments choose contractors: companies submit project proposals, and the one rated highest in the review is selected. It is often used for projection mapping projects. Examples of work scopes and contract caps are introduced in our article on projection mapping project costs in local government calls for proposals.

Subsidies

Programs that cover part of the cost of an event. Some, such as the Projection Mapping Promotion Support Subsidy of the Tokyo Metropolitan Government and the Tokyo Convention & Visitors Bureau, cover costs such as equipment rental. See also our article on subsidies for light events.

Guinness World Records

TOKYO Night & Light at the Tokyo Metropolitan Government No. 1 Building is certified by Guinness World Records for the “Largest architectural projection-mapped display (permanent),” at 13,904.956 m². For details, see our article on projection mapping Guinness World Records.

Frequently asked questions

What is the difference between projection mapping and an immersive exhibition?

Projection mapping refers to the technique of projecting images that fit the shape of a building or object, while an immersive exhibition refers to a form of exhibition that surrounds visitors with images and sound. Projection mapping techniques are often used within immersive exhibitions.

How bright a projector do I need to project outdoors?

There is no single figure, because it depends on the darkness of the surroundings, the size and color of the projection surface, and the viewing distance. The usual approach is to combine several high-brightness professional projectors and check the result with a test projection on site.

How do local governments commission projection mapping?

Many choose contractors through proposal-based competitions. The scope of work and contract caps are set out in the call for proposals, and some combine production, projection, installation and removal into a single contract.

*Information as of November 9, 2026.

*Top image: “City of Water: Edo Outer Moat” (from a press release by HITOHATA, INC.)

*This article was compiled by the TOKYO ART SPHERE editorial team based on related TOKYO ART SPHERE articles and public materials from the Tokyo Metropolitan Government, the Ministry of the Environment and others.

Text: TOKYO ART SPHERE Editorial Team

A note from the publisher

HITOHATA, INC., an affiliate of HITOHATA ASSOCIATION, the general incorporated association that operates TOKYO ART SPHERE, plans, directs, produces and operates projection mapping at National Treasures, Important Cultural Properties, World Heritage Sites and urban landmarks, as well as immersive exhibitions (“City of Water: Edo Outer Moat” in the top image is also one of its works). Inquiries, including those at the stage before a budget is set, are accepted through HITOHATA, INC.’s contact form (which has an option for local governments and public projects). Past projects are introduced on HITOHATA, INC.’s project page, and the company profile in our profile of HITOHATA, INC.