产品手册：

Measurement principle

 · Non-dispersive infrared spectroscopy (NDIR)

 · Photoacoustic spectroscopy (PAS)

 · Attenuated total reflection (ATR) spectroscopy

Target gas

CO, CO2, VOC, NOX, NH3, SOX, SF6, hydrocarbons, humidity, anesthetic gas, refrigerant, breathing alcohol gas, etc

Application

 · Medical care

   End-expiratory carbon dioxide chart, anesthetic gas detection, respiratory function monitoring, pulmonary function monitoring, respiratory alcohol gas detection, blood gas analysis

 · Industry

   Flammable and toxic gas detection, refrigerant monitoring, flame detection, fruit ripeness monitoring, SF6 monitoring, semiconductor manufacturing process.

 · Automobile

    CO₂ vehicle refrigerant monitoring, alcohol detection and alcohol lock, in-vehicle air quality monitoring

 · Environment

    Heating, ventilation and air conditioning (HVAC), indoor air quality monitoring, and volatile organic compound (VOC) monitoring

Blackbody radiation spectrum

Microscope image: MEMES chip in TO39 package (left).
The temperature distribution image of the film after heating (on the right).

Emissivity diagram

Blackbody dendritic surface structure

调制深度 VS 频率

Front and back photos of the infrared light source MEMS chip：

EMIRS200 (left), EMIRS50 (right).

Modulation frequency [HZ]

When driving the light source with a constant voltage pulse, a high-speed broadband detector is used for detection

Life reliability curve

Time [hour]

     In the service life reliability test, the dotted line indicates that the infrared light source operates in pulse modulation mode. The modulation frequencies of EMIRS200 and EMIRS50 are 10Hz and 30Hz respectively, with duty cycles of 62.5% for both. Solid lines indicate CW mode

     The mean time to failure (MTTF) of infrared light source film damage is obtained through statistical analysis of data collected from years of reliability experiments. The possibility of film damage largely depends on the type of packaging, the size of the input electrical power and the working mode.

滤光片的光谱透射率

辐射功率 VS 角度

The collimation effect of the reflective surface on the infrared radiation source along the axis
(Red area: High radiation distribution area.) Blue: Low-radiation distribution area

The principle of photoacoustic spectroscopy (PAS)

When infrared radiation energy is absorbed by the gas, the gas will be heated, leading to thermal diffusion and thereby increasing the pressure in the sample gas chamber. On the contrary, infrared radiation disappears and the gas cools, which leads to a decrease in pressure. Pressure fluctuations (such as sound waves) can be generated through modulated pulsed infrared light sources, which can then be detected by microacoustic sensors. The higher the concentration of the gas being measured, the stronger the signal (the wavelength of the gas being measured is selected through a narrowband filter). Photoacoustic spectroscopy (PAS) can be applied to gases, as well as solids and liquids.

The principle of attenuated total reflection (ATR)

     When radiation is total reflected at the interface, a small portion of it will be transmitted to the adjacent medium, forming an attenuated wave. This attenuation wave will decay exponentially with the penetration depth. The radiation intensity of the attenuated wave coupled to the interface depends on the refractive index difference between the two adjacent media. In the attenuated total reflection (ATR) method, a crystal made of a material with a high refractive index serves as a light-conducting medium. By coming into contact with the sample (usually a liquid), the attenuated wave interacts with it. Select the appropriate wavelength to pass through the corresponding narrowband filter.

     Depending on the state or quality of the sample, more or less light is coupled together, and the signal on the detector changes accordingly. Thermopile arrays or pyroelectric detectors are often applied in these devices.

  User graphical interface(GUI)

The driver circuit board of the infrared light source Labkit

· Based on LabVIEW software technology, it features a very simple user graphical interface (GUI)

· Real-time setting and update of driver parameters

· Real-time display of data and records through dynamic graphics

· Visualization of Limitations in Drive Mode (Recommended)

· It can output bitmap and Excel format data

· The RS232 interface and USB interface are directly connected to the compute

· Connect the infrared light source TO the socket or terminal block

· The analog input/output signal interface can be used as the synchronization signal for the detector