An Introduction to LIDAR

Updated on February 25, 2019
tamarawilhite profile image

Tamara Wilhite is a technical writer, industrial engineer, mother of 2, and a published sci-fi and horror author.

What Is Lidar?

RADAR stands for Radio Detection and Ranging. Radar relies on radio waves or RF to detect the speed, angle and distance of targets. Lidar is a modification of the well-known term radar, though it was developed two decades later. Lidar is not a form of radar. Instead, it is a detection system that uses the same principles of radar but uses lasers or light instead of radio or RF signals. That is why Lidar or LiDAR stands for Light Detection and Ranging.

Radar uses RF signals, while Lidar relies on light.
Radar uses RF signals, while Lidar relies on light. | Source

How Does Lidar Work?

Lidar systems don’t receive reflected sunlight. Instead, they generate a pulse of light and wait for the light signal to return. It uses the return time to calculate how far away the land feature is beneath it. Lidar becomes less accurate the more distant the target is. This can be because water in the atmosphere can interfere with the signal, plants absorb some of the signal, and the travel speed of the vehicle carrying it can cause reflected signals to travel at an angle. Lidar systems compensate by sending many data points that are consolidated to create an image. Lidar systems could send up to a million pulses a second.

How Is Lidar Used?

Lidar systems combined with GPS receivers are carried underneath airplanes, drones and helicopters to create precise, 3D maps. Topographical Lidar, Lidar that maps land, uses near-infrared lasers with wavelengths of 900 to 1060 nanometers. Bathymetric LIDAR maps water-features like rivers, marshes, and the shallow sea floor. That type of Lidar uses green light at roughly 500 nanometers that can penetrate the water. This explains why Lidar is regularly used for surveying.

DEM or digital elevation model specifically refers to the capture of elevation data. That information is needed to build roads and bridges.

The information from Lidar surveys is used to map flood plains, create flood models and determine flood risk. It can track variations in material density, so it can track slope changes and coastal erosion.

Lidar can be utilized when we want to determine the amount and type of plant cover in an area. The reflective pattern of trees in bloom is very different from grassy plains. Lidar can be used to track invasive plant species and the health of an ecosystem. The information from Lidar systems can be used to monitor coastal erosion and how much carbon a forest is absorbing.

Furthermore, Lidar allows for the accurate classification of land use. It helps planners determine which land is subject to farming, ranching, human habitation or remains wild. Lidar can help planners track the impact of human activity and determine which areas remain wild and should be off-limits to development. They can also see which areas are less productive and allowed to re-wild.

Lidar is being adopted quickly in the forestry industry. Lidar is starting to be used to map the amount of dead wood available to potential forest fires so that fire departments can engage in proactive fire management. Lidar also allows them to determine where trees are overcrowded or dying so that they can be removed before an infestation spreads or wood quality declines.

Elevation maps from Lidar and sunlight exposure area maps can be used by farmers to determine which area will have the highest yield. The data on how well vegetation is growing allows farmers to determine which spots need fertilizer and which are doing fine. The same sort of data analysis is used to determine the best locations for solar panels.

Because Lidar is both precise and pierces vegetation, it can often detect things hidden by vegetation. This explains why Lidar is increasingly utilized in archeology, though it is supplemented by ground penetrating radar.

Ground penetrating radar antennas
Ground penetrating radar antennas | Source

Lidar’s ability to map an area quickly has led to it being used to map crime scenes with minimal disruption to traffic.

The ability to detect the molecules near the surface mean it can aid in the discovery of mineral deposits. This is why Lidar is regularly used in the oil and gas and mining industries.

One of the most promising applications for Lidar is in self-driving cars. Lidar isn’t new to the automobile industry. Lidar has been utilized by cruise control systems to maintain the set speed while the driver guides the vehicle. Lidar is now being used to replace the driver. Self-driving cars are using basic Lidar scanners to detect obstacles and navigate streets. Like the cruise control systems, it measures the changes in vehicle speed, such as when it needs to slow down as it goes downhill. The LIDAR system also looks out for erratic movement in surrounding cars so that it could theoretically slam on the brakes before they hit. However, LIDAR cannot do the job on its own. Lidar systems cannot read traffic signs or traffic lights. This is why self-driving cars need visual cameras and radar, as well.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

Questions & Answers

    © 2019 Tamara Wilhite

    Comments

    Submit a Comment
    • Tim Truzy info4u profile image

      Tim Truzy 

      3 weeks ago from U.S.A.

      Interesting article, Tamara. Lidar has many promising advantages for science and the ordinary person. I saw on a science show how lidar helped archaeologists discover a previously unknown ancient city in Peru.

      Recently, I read about the invention of flying cars, which manufacturers hope to bring to the public. Maybe they will use this technology.

      In any case, you explained the technology well and provided a useful article for those curious about the topic.

      Thank you.

      sincerely,

      Tim

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, turbofuture.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://turbofuture.com/privacy-policy#gdpr

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)