What can terrestrial laser scanners do in cultural property surveys? 7 use cases

In the field of cultural property surveys, there is an increasing demand each year to record objects as non-invasively, comprehensively, and accurately as possible. Cultural properties range widely—temple and shrine architecture, stone monuments, ruins, traditional houses, historic sites, gardens, cave sites, and more—but they all share one thing: once a shape or condition is lost, it cannot be restored. That is why measurement technologies that preserve the current condition with high accuracy are valued.

Among these, terrestrial laser scanners have attracted attention as a method that fits very well with cultural property surveys. Because they can acquire three-dimensional shape data as large point clouds without touching the object, they make it easier to visualize complex ornamentation, subtle distortions, deflections from aging, and surface irregularities that cannot be fully captured by manual methods. This does not deny traditional hand measurements or photo-centered recording methods, but terrestrial laser scanners add significant value by filling in ranges that were previously difficult to cover.

On the other hand, many practitioners feel that while terrestrial laser scanners sound high-precision, it is unclear what they actually can do; they cannot clearly distinguish them from photogrammetry or general surveying; and it is hard to imagine which deliverables will result from adopting them. In cultural property surveys, simply creating three-dimensional data is not enough—what matters is how it connects to practical tasks like preservation, restoration, research, exhibition, maintenance, and report creation.

This article organizes what terrestrial laser scanners can do in cultural property surveys in a way that is easy to apply to real work. Focusing especially on the use cases that field personnel should know before issuing contracts or during planning, it introduces seven representative use cases. It also explains key ideas to ensure successful use and perspectives when combining scanners with other recording methods. If you want to improve the quality of cultural property surveys, increase the reproducibility of records, or leave data useful for future preservation and restoration, please read to the end.

Table of contents

• Why terrestrial laser scanners are attracting attention in cultural property surveys

• Use case 1 High-precision three-dimensional record of current conditions

• Use case 2 Understanding complex ornamentation and fine details

• Use case 3 Time-series comparison of deterioration and deformation

• Use case 4 Streamlining drafting and report preparation

• Use case 5 Creating baseline materials for restoration planning and preservation review

• Use case 6 Development into public use and exhibition content

• Use case 7 Recording that includes surrounding topography and the entire space

• Points for making terrestrial laser scanners effective in cultural property surveys

• Conclusion

Why terrestrial laser scanners are attracting attention in cultural property surveys

Terrestrial laser scanners are valued in cultural property surveys not simply because they are high-precision. The main point is that they make it easy to preserve the shape and condition of cultural properties in a form that can be reused for multiple purposes later. Manual measurements can accurately pick up required dimensions, but they rely heavily on the operator’s judgment, making it difficult to reconstruct areas that were overlooked during the survey. Photographs are excellent visual records, but they have limitations when strictly handling dimensions, depth, surface distortion, and positional relationships.

Terrestrial laser scanners acquire many measurement points on the object’s surface and save them as three-dimensional point cloud data. In other words, they can broadly preserve not only the information judged necessary on site but also information that might be needed in the future. In cultural property surveys, an initial survey intended merely to confirm the current condition can later be repurposed for restoration review, disaster recovery, public exhibition, or research materials. Therefore, securing data usable for multiple purposes from a single measurement is a major advantage.

Cultural properties also tend to have complex shapes. In addition to the alignment of columns and beams, survey targets include curved surfaces, carvings, warping, tilting, settlement, cracks, wear, and surface steps. For such complexity, terrestrial laser scanners—which capture extensive areas as collections of points rather than surfaces—are well suited, making it easier to find features that planar records alone would miss.

Non-contact measurement is also important in cultural property surveys. Conditions such as objects that are difficult to touch, areas where erecting scaffolding is impractical, places that cannot be approached, dark locations, and places where human entry must be restricted are not uncommon. Terrestrial laser scanners can measure widely from a distance, so they are often adopted as a method that enables recording while minimizing impact on the object.

Of course, they are not万能. There are caveats such as occlusions, materials that do not reflect well or complex recessed parts, designing measurement ranges, the effort of point cloud processing, and the importance of deliverable design. However, when used with an understanding of these issues, terrestrial laser scanners can greatly improve the recording accuracy, reproducibility, and reusability of cultural property surveys. So in what specific situations are they useful? The next sections describe seven representative use cases.

Use case 1 High-precision three-dimensional record of current conditions

The most basic and most important use is to create a high-precision three-dimensional record of the cultural property’s current condition. This is the starting point for introducing a terrestrial laser scanner.

In cultural property surveys, accurately preserving the current condition is often a major objective. For buildings, there are occasions to ascertain the deflection, tilt, and misalignment of columns, walls, roofs, eaves, and floors. For stone monuments, it may be necessary to capture not only overall dimensions but also the positions of losses, wear, weathering, and cracks. For ruins, subtle undulations of excavation faces or ground surfaces, stratigraphic relationships, and elevation differences with the surroundings can be important.

Using a terrestrial laser scanner, you can convert the entire object into a point cloud at a wide density, enabling you to extract necessary cross-sections later, verify dimensions at arbitrary positions, or magnify and inspect specific parts. Traditionally, it was necessary to decide in advance where and how many points to measure on site, but with point cloud data, you can broaden the scope of investigation later as long as it falls within the acquired range. This is a very significant advantage in terms of survey reproducibility.

Cultural property surveys often do not end with a single visit; they may continue across multiple years, with changes in personnel or with specialists from other fields joining later. If the current condition is preserved as three-dimensional data, stakeholders can more easily share the same object with the same criteria. Reducing the information that requires on-site presence and expanding what can be checked at a desk affects the quality of decision-making.

High-precision records of current conditions are also important for disaster or accident preparedness. Cultural properties can be severely damaged in a short period by fire, earthquakes, heavy rain, landslides, fallen trees, or aging. If an accurate pre-damage shape exists, it helps in considering restoration policies and comparing damage extents. Thus, terrestrial laser scanning plays a role not only in recording the present but also in preparing for future preservation responses.

If one phrase captures the significance of using terrestrial laser scanners in cultural property surveys, it is that they preserve the shape itself, not just the appearance. While photographs convey impressions and surface information, point clouds carry positional and shape information. Understanding this difference clarifies why three-dimensional measurement is emphasized from the stage of recording current conditions.

Use case 2 Understanding complex ornamentation and fine details

The value of cultural properties often resides not only in the overall appearance but also in the details. Carvings, patterns, joinery, stone surfaces, inscriptions, wear marks, machining traces, repair marks, and subtle differences in design can provide clues for historical interpretation, technical research, and preservation decisions. Terrestrial laser scanners are effective in capturing such complex shapes.

For example, in architectural cultural properties, not only the dimensions of columns and beams but also surface distortions, inconsistencies at joints, warping, and twisting of components can be important. For stone monuments, surface irregularities, the degree of inscription wear, traces of tooling, and the shape of fracture surfaces are survey targets. In parts of artifacts or ruins, subtle undulations or patterns of chipping can be more meaningful than surface smoothness.

Terrestrial laser scanners’ strength is that they can acquire the entire object broadly while preserving details at a certain resolution. Of course, when pursuing extremely fine surface information, close-range three-dimensional methods or high-resolution photographic representation can be advantageous. However, in practical cultural property surveys, it is important to read details while keeping their positional relationship with the whole. In that respect, terrestrial laser scanners, which balance wide-area recording and detailed capture, are very user-friendly.

Capturing fine shapes is important not merely for preserving appearance. To understand deformation trends by part, compare dimensional differences among similar components, confirm pre- and post-restoration differences, or interpret repair histories, three-dimensional information of details is necessary. In cases where visual inspection or photographs lead to divergent judgments, having point clouds or cross-sectional information can help advance discussions.

Also, what is visible on site can be difficult to articulate later in reports or meeting materials. In such cases, being able to generate views or cross-sections from the three-dimensional data in the required orientations makes it easier to share with specialists and explain to clients or managers. Cultural property surveying involves not only investigation but also communication. Capturing and visualizing fine shapes supports both.

Use case 3 Time-series comparison of deterioration and deformation

Although cultural properties are preserved, they cannot completely escape the effects of time. Wind and rain, temperature and humidity changes, freeze-thaw cycles, ground movement, vegetation impact, human load, and material aging gradually change conditions. Therefore, recording at multiple time points for comparison is important. Terrestrial laser scanners excel at time-series comparisons.

For example, comparing point clouds is useful to confirm how much a building column’s tilt progressed over several years, where stone steps are experiencing wear, whether bulging in a stone wall is expanding, if wall deformation is spreading, or the direction in which erosion of a ruin surface is progressing. Differences can be seen to some extent by comparing photographs, but three-dimensional data makes it easier to quantify shape changes.

In preservation management of cultural properties, it is important not only to know whether change occurred but also where, to what extent, and in which direction. If terrestrial laser scanner data from multiple time points are aligned, cross-section comparisons and difference checks make it easier to read deformation and wear trends. This helps judge the need for restoration and prioritize interventions.

Time-series comparison also aids early detection of anomalies. Gradual deformations that are hard to notice visually may show signs when viewed over time. For cultural properties, reacting only after severe damage occurs is too late; the value is in considering measures while changes are still small. In this way, terrestrial laser scanners can serve as tools for both recording and monitoring/preventive maintenance.

Moreover, time-series comparison results are useful for accountability. It becomes easier to show with data, not feelings, why repairs are needed and which parts require priority attention. When forming consensus among managers, owners, administrators, and experts, being able to present changes in an easily understandable form is important. For this reason, the role of terrestrial laser scanners in continuous cultural property surveys is significant.

Use case 4 Streamlining drafting and report preparation

Cultural property surveys ultimately require organizing results into reports and drawings. Measurement on site is not the end; producing plans, elevations, cross-sections, site layouts, component location diagrams, and explanatory plates is necessary to make survey results usable. Point cloud data from terrestrial laser scanners contributes to streamlining this drafting and report preparation.

Traditionally, drafting involved taking necessary dimensions on site and creating drawings while referencing photographs. But cultural properties are not always composed of straight lines and right angles; distortions and inconsistencies often exist in reality. When drafting such targets, limited measurement points can make faithful reproduction difficult and may require site re-verification. With point clouds obtained by terrestrial laser scanning, you can extract cross-sections at arbitrary positions and produce drawings closer to the actual shape.

The improvement of as-built drawing accuracy is particularly effective. In cultural property surveys, what matters is not an ideal design drawing but what actually exists now. Cross-sections and elevations derived from point clouds can represent tilt, settlement, deflection, and component offsets, making them useful for drafting that reflects current conditions.

During report preparation, additional perspectives may be needed later. For example, even if only a frontal elevation was initially planned, review or consultation stages may require cross-sections from different angles or enlarged details. If the original point cloud data are well prepared, you are more likely to be able to create additional drawings without re-measurement. This flexibility in work is a major benefit.

Of course, having point clouds does not automatically produce good drawings. It is important to clarify in advance what deliverables are required, the needed accuracy and level of detail, and which sections are practically important. Even so, having multi-faceted data of current conditions dramatically strengthens the foundation for drafting and report compilation. Terrestrial laser scanners support not only fieldwork but also the quality of office work in connecting survey results to practical outputs.

Use case 5 Creating baseline materials for restoration planning and preservation review

One important objective of cultural property surveys is preparing materials for restoration and preservation decision-making. Even when immediate construction or repair is not performed, it is crucial to record current conditions, organize the extent of deformation and damage, and provide common materials for stakeholders to discuss future responses. Terrestrial laser scanner data can be used as baseline materials for restoration planning and preservation review.

For example, if part of a structure is leaning, you may want to determine whether the deformation is localized or affecting the whole. For stone walls or stone pagodas, you need to judge whether a single component has shifted or deformation has occurred from the foundation. For ruins, you might need to organize the relationship with current terrain for considering protective embankments or managing exposed areas. In these situations, checking cross-sections and shape trends from point cloud data is useful for preservation policy consideration.

Restoration planning requires determining which parts to retain, which to reinforce, and how far intervention should extend. This judgment requires not only accurate shape understanding but also grasping the continuity of deformation and relationships between components. Terrestrial laser scanners make it easier to view the object as a whole, enabling examination of local problems within the global structure.

In cultural property preservation, avoiding excessive intervention is also important. Therefore, carefully recording the current state before restoration and clarifying what is original is necessary. Three-dimensional records by terrestrial laser scanning align well with this principle of preserving the existing condition, serving as documentation for later verification. They also provide a standard for verifying which parts changed and to what extent after restoration.

Terrestrial laser scanner data are also effective for building consensus among stakeholders. Preservation and restoration involve not only survey personnel but owners, managers, designers, contractors, and scholars. When plans are not easily conveyed by plans and photographs alone, three-dimensional shape data make it easier to share understanding. The goal of preservation review is not to rush to the correct answer but to gather decision-making materials. In that sense, terrestrial laser scanners form an important foundation supporting the pre-restoration phase.

Use case 6 Development into public use and exhibition content

Data obtained in cultural property surveys can be used not only for preservation and research but also for public use. Recently, there has been emphasis on digital exhibits, remote viewing, educational use, and enhancing public materials to communicate the value of cultural properties to more people. Three-dimensional data from terrestrial laser scanners are effective source material for such public use.

For example, for places that are usually inaccessible or difficult to open to the public for preservation reasons, three-dimensional data make it easier to convey the shape and spatial composition. Data can be developed into figures for exhibition panels, footage for explanatory videos, three-dimensional browsing materials, and comparative displays, making information easy to understand for visitors and learners.

The appeal of cultural properties often cannot be conveyed by a single photograph. For example, the depth of architectural spaces, the three-dimensionality of stone monuments, elevation differences of ruins, and positional relationships between components are more easily communicated with three-dimensional information. In public use, ease of communication as well as accuracy matters, and terrestrial laser scanner data help achieve both.

For educational uses as well, three-dimensional data are valuable. Being able to confirm shapes without visiting the site facilitates school education, community learning, preservation awareness, and specialist training. Especially when survey results are shared broadly rather than confined to reports, it enhances the social value of cultural properties.

Of course, if public use is the goal, it is important to separate how to present data from how to preserve it. Survey data may be high-density and specialist-focused, while public-facing material requires clarity and ease of handling. However, if the underlying three-dimensional record is solid, it is easier to adapt representations to different purposes. The value of using terrestrial laser scanners in cultural property surveys thus extends beyond field records to the question of how to communicate about cultural properties.

Use case 7 Recording that includes surrounding topography and the entire space

Cultural properties do not always exist in isolation. For buildings, the relationship with precincts, approach paths, stone walls, retaining walls, and surrounding slopes can be important. For ruins, terrain, cut-and-fill traces, surrounding ruins, circulation routes, water flow, and visibility relate to interpretation. Even for stone monuments, the installation position, plinth, surrounding ground, and relationships with nearby structures can hold value. Terrestrial laser scanners are effective because they can record not only the cultural property itself but also the surrounding space.

In cultural property surveys, it is not enough to merely take dimensions of the object. It is important to understand where, in what condition, and in what relationship to the surroundings the object exists. For instance, if ground slope or rainwater flow affects preservation conditions, measurements of the cultural property alone are insufficient. Recording surrounding elevation differences and structure placement makes preservation issues easier to identify.

Understanding the entire site’s space also helps in survey planning and management planning. Considerations such as visitor circulation, setting restricted access zones, organizing maintenance areas, and planning temporary facilities require a spatial understanding that includes the surroundings in order to both protect and utilize cultural properties. If a terrestrial laser scanner records a wide area, these considerations can proceed on the same base dataset.

Furthermore, relationships between individual elements can become research themes in cultural property surveys—for example, the correspondence between architecture and topography, the relationship between ruin placement and landform, or the orientation of stone monuments relative to nearby facilities. Spatial relationships that are hard to read from two-dimensional drawings are often easier to understand with three-dimensional data. This is useful not only for research but also for creating explanatory materials for the public.

Recording cultural properties often focuses on the object’s surface, but it is important to record the environment as well. Terrestrial laser scanners make it easier to translate this perspective into practice. To view cultural properties as places rather than isolated points, recording that includes surrounding space will become increasingly important.

Points for making terrestrial laser scanners effective in cultural property surveys

We have reviewed use cases, but adopting a terrestrial laser scanner does not automatically produce results. To use them effectively in cultural property surveys, you need to address several practical points.

First, clarify in advance what deliverables you want. Whether the goal is current-condition recording, drafting, time-series comparison, restoration review, or exhibition use changes the required measurement density, range, occlusion mitigation, and registration strategy. If you measure broadly without a clear purpose, the data volume may balloon and become difficult to handle downstream.

Next, consider how to reduce occlusions. Terrestrial laser scanners efficiently measure visible ranges, but rear sides, narrow or complex areas, and areas in the shadow of obstructions are harder to acquire. Because cultural properties often have complex shapes, it is important to anticipate where data gaps are likely and carefully plan measurement positions. on-site decision-making affects the quality of results.

Also, avoid trying to complete the survey with point clouds alone. Cultural property surveys include elements that point clouds cannot fully express—color and texture, the appearance of deterioration, material information, and inscriptions. Combining photographic records, existing drawings, field notes, and visual observations increases the practicality of survey results. Terrestrial laser scanners can be the main tool, but they are not a universal solution by themselves.

Do not overlook how deliverables are handed over and managed. Point cloud data are voluminous, so consider formats that stakeholders can view easily and organizational methods that will remain usable over time. Data from cultural property surveys may be referenced years or decades later. Organize measurement ranges, coordinate handling, creation dates, target scope, and deliverable composition so future users can understand them.

In addition, linking with positional information provides great value in cultural property surveys. Even if a single object’s shape is precise, unclear relationships with surroundings can hinder management, re-measurement, comparison, and overlay with other data. If you consider consistency across a site or with surrounding facilities, prepare three-dimensional data so they are easy to treat spatially. This perspective is essential to make survey data more than one-off records and to utilize them for maintenance or additional surveys.

Conclusion

The role of terrestrial laser scanners in cultural property surveys goes beyond mere high-precision measurement. Their uses are broad: three-dimensional records of current conditions, understanding complex fine shapes, time-series comparison of deterioration and deformation, streamlining drafting and report preparation, creating baseline materials for restoration planning and preservation review, development into public use, and recording that includes surrounding spaces.

In particular, for targets like cultural properties that are difficult to touch, have complex shapes, and require long-term preservation, leaving three-dimensional data that can be referenced later is highly valuable. Reducing on-site oversights, enabling stakeholders to share the same object, and facilitating future comparisons and uses are major practical strengths.

At the same time, to truly integrate cultural property surveys into practice, it is important not to leave acquired point clouds as isolated data. Measurement data must be connected with drawings, site photographs, management information, and positional data to raise the quality of preservation, survey, and maintenance. Especially in wide sites or surveys spanning multiple locations, a system that ensures positional consistency along with three-dimensional records will determine downstream usability.

If you want to record, share, and manage measured data more dynamically on site while linking them to local positional information, using LRTK is also effective. As an iPhone-mounted GNSS high-precision positioning device, LRTK supports on-site positioning and improves recording accuracy, helping to lay the groundwork for handling three-dimensional data from terrestrial laser scanners together with surrounding information. What cultural property surveys need is not merely more measuring devices but ensuring that necessary information is reliably recorded on site and organized in a form usable for the future. Combining three-dimensional records from terrestrial laser scanners with high-precision positional systems like LRTK can further enhance the accuracy and operability of cultural property surveys.