光纤激光器具有光束质量好、能量密度高、电光转换效率高、散热好、结构紧凑、免维护、传输灵活等优点。已成为激光技术发展的主流方向和应用的主力军。光纤激光器的整体电光效率为30%~35%，大部分能量以热量的形式散失。

因此，激光器工作过程中的温度控制直接决定了激光器的质量和使用寿命。传统的接触式测温方式会破坏激光器本体的结构，而单点非接触式测温方式无法准确捕捉光纤温度。利用红外热像仪在光纤激光器生产过程中检测光纤，尤其是光纤熔接处的温度，可以有力地保证光纤产品的开发和质量控制。生产测试过程中对泵浦源、合束器、尾纤等进行测温，保证产品质量。

在应用端红外热成像测温还可以在激光焊接、激光熔覆等场景进行测温。

红外热像仪应用于光纤激光器检测的独特优势：

1、红外热像仪测温具有远距离、非接触、大面积测温的特点。

2、专业测温软件，可自由选择监测温度区域，自动获取和记录最高温度点，提升测试效率。

3、可设置温度阈值、定点采样，多次测温，实现数据自动采集和曲线生成。

4、支持多种形式的超温报警，自动根据设置值判定异常，自动生产数据报告。

5、支持二次开发和技术服务，提供多平台SDK，方便集成开发自动化设备。

Infrared application

1、光纤熔接点质量监测

在大功率光纤激光器的制造过程中，光纤熔接处可能存在一定尺寸的光学不连续性和缺陷，严重的缺陷会导致光纤熔接处异常发热，从而对激光器造成损坏或烧掉热点。因此，光纤熔接接头的温度监测是光纤激光器制造过程中的一个重要环节。使用红外热像仪可以实现对光纤熔接点的温度监测，从而判断被测光纤熔接点的质量是否合格，提高产品质量。

使用在线式红外热像仪集成到自动化设备上，能够稳定快速的测试光纤温度，提高生产效率。

图1 光纤测温

2、LD泵浦源

单个LD芯片输出的激光功率是有限的。 Pumping 将多个 LD 芯片封装在一起，以增加输出功率。泵浦产生大量热量，因此温度直接影响芯片输出的激光波长。使用红外热像仪对每台泵的来料进行质量检测，不合格的泵退回，保证激光器质量。

泵浦输入输出光纤温度检测。

图2 泵浦温度检测

3、合束器温度检测

合束器的作用是将N个泵浦激光合并为一个激光，实现激光的高功率输出。使用红外热像仪进行工作温度测试，可以对合束器工作是否正常进行判别，提升产品品质。

图3 光纤合束器

4、Laser welding

由于激光焊接的温度很高，所以采用的红外热像仪必须能够测量很高的温度，还要求温度范围广，我们的红外热像仪器测温范围-20-1600℃，可满足焊接过程中的温度范围。

由于焊接的升温过程和整个焊接过程都比较快，所以要采用帧频较高的高速红外热像仪，使用在线式红外热像仪帧率50HZ/100HZ，可以快速捕捉温度变化。由于激光焊接的特殊环境，所以人必须能远离焊接现场，使用红外热像仪能够在线实时进行测温在后台操作。

红外热成像是探测长波红外（8-14um波长）进行成像和测温，不受激光光源的影响。

5、激光熔覆熔池测温

激光熔覆熔池温度变化快，熔池区域小，使用热成像测温可以准确的捕捉到温度的变化和熔池温度场的分布。红外热成像可最高测试2000℃的熔池温度。

在线式红外热成像测温仪—功能特性

（1）超高的响应范围

采用分段式测温参数调取，测温范围多档可选，涵盖-20℃~1600℃，在这个范围内可以实现正常测温，测温精度可达±2%，超出这个范围也可以正常成像。

（2）采用高帧频设计

可以观测快速移动的目标，常规产品帧率25Hz/50Hz，特殊的应用场景还有100Hz高速红外成像测温产品。

（3）采用高透过率无热化镜头

前片镀碳膜，不加装锗窗的情况下也可以起到一定的保护作用，另外也有高透过率的锗窗保护罩可以选配，适应各种恶劣使用场所。

（4）采用千兆网设计网线传输

既保证了远距离传输又保证了传输的可靠性，同时也可让人原理现场环境。

（5）输出全码流无损16Bit温度数据

提供客户端软件及SDK开发包，便于客户进行二次开发和系统集成，充分对被测目标进行个性化温度分析。

3、Applicable Machine

KB26E31 微距红外热成像测温仪

K26E35 Online Infrared Thermal Imaging Thermometer

了解更多应用详情，欢迎致电华景康红外咨询专线：400-080-4288。

Applicable Machine

1.Basic principles of infrared thermal imaging

Generally, the visible light wavelength that our human eyes can feel is 0.38~0.78 μ m。 Usually we will compare 0.78 μ M long electromagnetic waves are called infrared rays. In nature, all objects whose temperature is above absolute zero (-273 ℃) will emit infrared rays. Therefore, infrared images, also known as thermal images, can be obtained by detecting the infrared radiation of objects with detectors.

Figure 1 Infrared spectrum segment

The infrared thermal imaging system receives the infrared ray emitted by the object, and after a series of processing, it can form the thermal image of the object surface and measure the temperature of relevant parts. Because the infrared thermal imaging system passively receives the infrared thermal radiation of the target itself, it has nothing to do with climatic conditions, so it can work normally no matter day or night. Due to the short wavelength of visible light and the poor ability to overcome obstacles, the observation effect is poor and even can not work under the bad weather conditions such as rain, snow and fog. Compared with visible light, infrared has a longer wavelength, especially when working at 8~14 μ M thermal imager not only has high ability to overcome rain, snow and fog, but also reflects good temperature detection characteristics. Therefore, the target can still be observed normally at a long distance. Therefore, the infrared thermal imaging monitoring equipment can reliably monitor and warn various targets at night and in severe weather conditions.

Figure 2 Partial application of infrared detection

Any object will release infrared ray. The infrared thermal imager uses the infrared detector and optical imaging objective lens to receive the infrared radiation energy distribution pattern of the measured target and reflect it on the photosensitive component of the infrared detector, so as to obtain the infrared thermal image, which corresponds to the thermal distribution field on the surface of the object. In the path of heat flow diffusion and transmission inside the object, due to the different thermophysical properties of materials or conduction, it will be blocked to accumulate, or unobstructed to transmit, and finally form the corresponding "hot zone" and "cold zone" on the surface of the object. This phenomenon of temperature difference from the inside and the surface is the basic principle of infrared detection. Because the infrared response band is 8~14 μ m. It will not be affected by laser during welding.

Figure 3 Partial application of infrared detection

2. Technical requirements

Because the temperature of laser welding is very high, the infrared thermal imager used must be able to measure very high temperature, and it also requires a wide temperature range.

Because the heating process and the whole welding process are relatively fast, a high-speed infrared thermal imager with high frame rate should be used.

For the lens, it is also necessary to provide a protective device, which can not only transmit the infrared radiation of the corresponding wave band, but also block the damage of welding spatter to the infrared thermal imager lens, and also eliminate the interference and influence of welding arc.

Due to the special environment of laser welding, people must be far away from the welding site, and the selected infrared thermal imager must be able to operate remotely.

Laser welding equipment has some advantages and disadvantages in welding speed and welding operation. In the future welding field, we should deeply study the reaction mechanism and phenomenon of laser welding process, absorb and master the international advanced welding technology and measurement and control technology, and realize the nationalization and autonomy of laser measurement and control technology.

3. Product response

The on-line infrared thermal imaging thermometer adopts imported 17 μ M uncooled infrared focal plane detector, high-performance infrared lens and signal processing circuit, and embedded with advanced image processing algorithm, it has the characteristics of small size, low power consumption, fast startup, excellent imaging quality, accurate temperature measurement and so on.

The device selection of on-line infrared thermal imaging thermometer fully considers the requirements of high and low temperature working performance to ensure that the whole machine has excellent environmental adaptability.

Functional characteristics of online infrared thermal imaging thermometer:

1. The ultra-high response range adopts segmented temperature measurement parameters, and the temperature measurement range covers -20 ℃ ~1600 ℃. Within this range, normal temperature measurement can be achieved, and the temperature measurement accuracy can reach ± 2%. Beyond this range, normal imaging can also be achieved;

2. With high frame rate design, it can observe fast-moving targets, up to 100Hz;

3. Using a high transmittance non heated lens, the front piece is coated with carbon film, and it can also play a certain protective role without adding germanium windows. In addition, there are also high transmittance germanium window protective covers that can be selected to adapt to various harsh places of use;

4. Using gigabit network to design network cable transmission, not only ensures long-distance transmission, but also ensures the reliability of transmission;

5. The full stream lossless 16bit temperature data is output, and the client software and SDK development kit are provided to facilitate the secondary development and system integration of customers, and fully carry out personalized temperature analysis of the tested target.

Applicable model:

K23E19 online infrared thermal imaging thermometer adopts 17 μm uncooled infrared focal plane detector, high-performance infrared lens and signal processing circuit, and embedded image processing algorithm, with small size, low power consumption, fast start-up, excellent imaging quality, accurate temperature measurement and other characteristics.

The device selection of k23e19 on-line infrared thermal imaging thermometer fully considers the requirements of high and low temperature working performance to ensure that the whole machine has excellent environmental adaptability.

Functional Characteristics

1. It has all-weather passive thermal imaging function, has strong smoke penetration performance, and can be used in a wide range of ambient temperatures;
2. With high frame rate design, fast-moving targets can be observed;
3. Adopt self-developed temperature measurement correction algorithm to realize accurate temperature measurement;
4. Output full stream lossless 16bit temperature data, and provide client software and SDK development kit.

Application Field

Power Grid, Petroleum And Petrochemical, Rail Transit, Circuit Detection

Scientific Research, Security Monitoring, Machine Vision, Customized Development