Applications | ATR6100 280g Handheld Raman On-Site Identification

On a subway platform at night, an invisible near-infrared beam is reading the molecular fingerprint inside a bottle.

At 9:17 p.m., just before the last train on Subway Line 2 arrived. “Wait—someone left a bag,” Lao Zhou shouted. The person did not turn back and quickly disappeared at the top of the escalator.
 

The duty station master came over. The two put on gloves and moved the bag to the table in the security room. The zipper opened: inside were a coat, a bottle of mineral water, and a small glass bottle wrapped in newspaper. Inside the bottle was white powder. In the past, the procedure at such a moment was: seal off the scene, evacuate the platform, and wait for the bomb squad. After the bomb squad arrived, they would first screen with test strips—but a test strip can only test one target at a time. Methamphetamine is one line, heroin another, ketamine yet another. Anything the strips could not detect still had to be sampled and taken back to the laboratory.

That night, Lao Zhou pulled something out of the holster on his belt. It looked like a miniature body camera, or a toy pistol: blue-gray color, a small round opening at the front of the barrel, a button on the side, and the whole unit weighed only 280 grams. He pointed the muzzle at the small glass bottle and pressed the button. An invisible near-infrared beam shot out from the barrel. Three seconds later, the police terminal phone on his belt dinged, and a line of text appeared on the screen: Acetonitrile, flammable liquid, match 100%.
 

Not a drug, not an explosive—just a common organic solvent found in laboratories. A false alarm, but at least—an answer in three seconds. The device in Lao Zhou’s hand is the ATR6100, Optosky’s fourth-generation ultra-micro handheld Raman spectrometer.
 

This article does not present a parameter table. It answers one question: how does a 280-gram “pistol” identify what is inside a bottle in three seconds?

01  The Invisible Beam Is “Shaking Hands” with Molecules

The button Lao Zhou pressed triggered a 785 nm near-infrared laser. This wavelength is invisible to the naked eye, but its energy is just right—enough to “touch” molecules without igniting the contents of the bottle. The laser entered the glass bottle, passed through the glass, and hit the white powder. The vast majority of photons bounced back unchanged, like ping-pong balls hitting a wall. But a very small number of photons, on their way back, “exchanged” a little energy with the chemical bonds in the molecule. In this back-and-forth, the color of the light shifted extremely slightly. Different molecules have different chemical bonds and exchange energy in different ways. Plotted as a curve, these shifts become the “fingerprint” of that molecule. Acetonitrile has an acetonitrile fingerprint; heroin has a heroin fingerprint; TNT has a TNT fingerprint. These fingerprints were measured and stored in databases by chemists long ago. What the “pistol” in Lao Zhou’s hand essentially does is: shine light, obtain the on-site fingerprint, and compare it with more than 20,000 standard fingerprints stored in the phone. If there is a match, the phone tells you what it is; if not, it honestly says “unknown.” The whole process requires no opening the bottle, no sampling, no pretreatment, and no laboratory. It can measure through glass, through plastic bags, and through ordinary transparent packaging.

02  Compressing a Laboratory Instrument into 280 Grams

The principle of Raman spectroscopy was discovered by Lord Raman in 1928. But for a long time, it was a bulky piece of laboratory equipment—an optical table, several lenses, and a liquid-nitrogen-cooled detector, occupying an entire desk. Making it 280 grams, pocketable, and able to work normally on a subway platform at minus 20 degrees Celsius—where is the difficulty?
 

The difficulty is “making the optical path accurate in such a small volume.” The core of a Raman spectrometer is the dispersion system—it must split the returning beam into different colors and precisely measure the intensity of each color. Traditional approaches use large prisms and mirrors, with optical paths tens of centimeters long. Optosky turned the entire dispersion system into a patented ultra-micro structure and packed it into a 150 × 150 × 45 mm pistol grip.
 

The difficulty is “making the linewidth narrow in such a small laser module.” The narrower the laser linewidth, the clearer the fingerprint. The ATR6100 uses a self-developed ultra-micro 785 nm laser module with 100 mW power—not much brighter than a phone flash—but enough to excite Raman signals.
 

The difficulty is “putting the computing power not in the instrument, but in the phone.” This is its most different design compared with traditional portable instruments: the instrument itself is only responsible for collecting light and producing spectra. The real work—running recognition algorithms, storing 20,000 fingerprints, and performing matching—is done by the police terminal phone on Lao Zhou’s belt. Once connected via Bluetooth, the instrument becomes a peripheral of the phone. This is also why it can achieve 280 grams—the battery, processor, screen, and spectral library are all offloaded to the phone.
 

The difficulty is “it must truly work on the front line.” IP65 dust and water resistance means it can be used at rainy subway entrances, dusty warehouses, and bumpy law enforcement scenes. An operating temperature range of minus 20 to 50 degrees Celsius means it can start up from Harbin winters to Wuhan summers. The battery lasts four to six hours—enough for one shift. USB-C charging means one cable, the same as a phone.
 

The unit in Lao Zhou’s hand is the ATR6100DH—DH stands for the “drug enforcement” version. It comes preloaded with fingerprint libraries for common drugs such as heroin, methamphetamine, cocaine, and ketamine; explosives such as TNT, RDX, and TATP; and hazardous chemicals such as sulfuric acid, gasoline, nitric acid, and toluene.

It is not a gun. It is a scanner housed in a gun-shaped shell that can read molecular fingerprints on site.
 

03  The Same “Gun” Is a Different Tool in Different Hands

In Lao Zhou’s hands, it is a security inspector. The DH version contains fingerprint libraries for drugs, explosives, precursor chemicals, and common hazardous chemicals. At subway entrances, high-speed rail stations, and BRT hubs, when encountering unattended packages, suspicious liquids, or powders no one dares to touch, take it out and shine it—within seconds you have a preliminary answer.
 

In the hands of a pharmaceutical factory QA, it is a raw and auxiliary material identification instrument. The PH version is specifically for pharmaceutical factories—when a shipment of API arrives at the warehouse, before unloading, shine it at the packaging bag and confirm in three seconds whether this batch is the specified material. No need to sample every batch and send it to the central laboratory; non-conforming materials can be rejected on the spot. It is also compatible with CFR 21 Part 11 and can generate electronic reports compliant with GMP specifications.
 

At a jewelry store counter, it is an identification instrument. The GM version contains fingerprint libraries for diamonds, agate, jadeite, and various gemstones. When a customer brings a loose diamond to sell, the owner picks it up and shines the device on it—natural or synthetic, whether there is filling treatment—the result appears directly on the screen. No need to send the goods to a third-party appraisal center and wait three days.
 

On a factory incoming inspection line, it is an industrial sorting instrument. The IN version contains fingerprint libraries for common chemicals, plastics, rubber, and polymer materials. When recycled plastics are piled mountain-high, sample a few points and shine the device—is this batch PE or PP, how much impurity is mixed in—within seconds you have an idea.
 

The same hardware, four industry versions, behind which is the same logic: compress the answer time to the question “what is this” from days to seconds.

04  What It Cannot Do Is More Important Than What It Can Do

After discussing capabilities, the boundaries must be made clear. Otherwise, when Lao Zhou and others take it onto the street, there will be problems.
 

First, it can recognize “what is in the library,” but not “what is not in the library.” A library of 20,000 fingerprints sounds like a lot, but there are tens of millions of chemical substances in the world. When encountering a new mixture or a new psychoactive substance not included in the library, it can only tell you “unknown peak,” not “this is a certain new drug.” At that point, the sample still has to be sent to a laboratory for mass spectrometry.
 

Second, for complex mixtures it can only perform preliminary screening. If a bottle does not contain a pure substance but a mixture of several things—for example, drugs cut with lactose, caffeine, or starch—the spectra will overlap, and identification confidence will decrease. Precision algorithms can detect mixtures, but that does not mean it can separate and quantify every component in the mixture.
 

Third, samples with strong fluorescence can fail. Dark plastics, colored liquids, and certain herbal powders emit strong fluorescence under 785 nm laser excitation, covering the Raman signal. In such cases, a 1064 nm version is needed—the ATR6100 does have a 1064 nm model, but that is another SKU; you cannot simply switch wavelengths on site.
 

Fourth, it provides a “preliminary screening conclusion,” not “legal evidence.” Lao Zhou used it to identify “acetonitrile, 100%.” This conclusion can be used to decide whether to evacuate and whether to upgrade the response. But for formal case filing, formal submission for testing, and formal court proceedings, national standard methods must still be followed, qualified laboratories must be used, and CMA/CNAS reports must be issued. It is a sentinel, not a referee—this statement was made in the previous two articles, and it still holds here.
 

Fifth, it must not be pointed at people. Although a 100 mW near-infrared laser is not as dazzling as visible light, prolonged exposure to the eyes is risky. On-site use has strict operating procedures; it is not something to casually pick up and point.

At 9:47 that night, Lao Zhou and the duty station master put the small glass bottle into an evidence bag. After confirming it was acetonitrile, the passenger was also contacted—a student from a nearby university chemistry department who had left the bag behind while rushing for the last train. A false alarm.

But without that 280-gram “pistol,” this “false alarm” might have lasted three hours: sealing off the platform, evacuating passengers, the bomb squad entering, sampling, and waiting for laboratory results. Three hours would mean the last train on Line 2 stopped running, hundreds of passengers stranded, and service restored only before the next morning’s rush hour.

The meaning of technology is sometimes not how earth-shattering a thing it can do. It is that it turns something that originally took three hours into three seconds. From a full optical table to a 5-kilogram carrying case, and then to a 280-gram pistol that fits in a pocket—the path Raman spectroscopy has traveled over these decades is essentially one sentence: take the precision instrument from the laboratory and, step by step, place it in the hands of the people who most need to make judgments on site.

If you are engaged in the following work, this device is worth learning about:

Security inspection and rapid hazardous chemical screening at subway/high-speed rail stations and ports

Incoming identification of raw and auxiliary materials in pharmaceutical factories (GMP/CFR 21 compliance)

On-site identification at jewelry stores and pawnshops

Incoming inspection at chemical plants and recycled plastic sorting

On-site preliminary screening for police drug enforcement and emergency response.

For more information, please contact:

Email: [email protected]

Web: www.optosky.net