Spectrometers enable high-precision spectral analysis of the structure and composition of substances. Applying principles of dispersion, diffraction, or optical modulation, they decompose light radiation of different frequencies according to certain rules, forming a spectrum. Combined with a series of optical, precision mechanical, electronic, and computer systems, they achieve the precise measurement and study of the frequency and intensity of light radiation.

Miniature fiber optic spectrometers use fiber optic connectors as the incident light interface, employ folded optical paths and fixed gratings for spectral dispersion, and array image sensors as detectors for spectral detection. They are characterized by their small size, rapid detection, and ease of use, making them ideal for online, in-situ, and portable applications in scientific research and industry.

01 Principles of Spectrometers

The basic principle of a spectrometer is that polychromatic light passes through a slit and is collimated onto a grating. Due to the dispersion effect of the blazed grating, different colors of light have different diffraction angles and will separate from each other, eventually focusing and imaging onto different positions of a linear CCD. Through calibration, the spectral information of the light source can be obtained by acquiring the wavelength and intensity values ​​of the corresponding pixels.

Key components and functions of fiber optic spectrometers:

Collimating element: Makes the light emitted from the slit parallel.

Focusing element: focuses the well-splitted light beam onto the photosensitive area of ​​the detector.

Fiber optic interface: The signal beam is transmitted through a standard optical fiber, coupled via the fiber optic interface, and enters the spectrometer.

Entrance slit: Before the signal beam enters the spectrometer, it must pass through an entrance slit, allowing only a suitable amount of light signal to enter the spectrometer. The size of the entrance slit affects parameters such as the spectrometer's resolution and sensitivity.

A grating disperses an optical signal into multiple beams in space according to wavelength. The grating, which separates incident light, is a core component affecting the main performance of a spectrometer, determining its spectral range and resolution.

02 Dimension-Labs Fiber Optic Spectrometer

Dimension-Labs offers a series of fiber optic spectrometers covering the spectral range of 190–2500 nm, including ultraviolet, visible, and near-infrared wavelengths. The spectrometers are available in six series: general-purpose, high-resolution, high-sensitivity, cooled, deep-cooled, and near-infrared. Their performance parameters cater to various levels, including educational, industrial, and research applications, making them suitable for diverse environments such as laboratories, research facilities, and industrial settings.

General-purpose spectrometer

• Small size, high performance, low temperature drift
• Online measurement, industrial site, equipment integration
• High sensitivity, low stray light, and elimination of higher-order diffraction.
• Cross-type CT optical path design, high-sensitivity linear CMOS image sensor, imported high-quality grating

High-resolution spectrometer

• Telephoto imaging design, high line-to-plane blazed grating 
• Optimal resolution of 0.07 nm, stray light as low as 2‰ 
• Full spectrum from 200 to 1100 nm, custom spectral range
• Laser measurement, plasma emission spectroscopy, LIBS spectroscopy measurement

High-sensitivity spectrometer

• A CCD array with a pixel count of 2048 × 64. 
• High-speed processing chips and algorithms enable millisecond-level spectral detection. 
• Absorption spectroscopy, near-infrared spectroscopy, and deep ultraviolet spectroscopy
• High-sensitivity back-illuminated CCD with deep ultraviolet quantum efficiency up to 70%.

Ultra-high speed spectrometer

• The shortest integration time is as low as 6µs.
• Stray light <0.1%, significantly improving spectral accuracy.
• Detection speed can reach 2000 frames per second, suitable for high-frequency data acquisition.
• Compatible with multiple interfaces such as GIGE, USB, and HDMI, offering flexible expansion capabilities.

Cooled spectrometer

• Good stability and spectral repeatability
• -5℃ cooling, low noise, high signal-to-noise ratio
• Cooled, back-illuminated CCD image sensor
• Meets the needs for stable testing over long periods of time in both field and scientific research.

Deep-cooled spectrometer

• Extremely low readout noise
• -25℃ deep-cooling CCD, excellent temperature stability
• Suitable for applications requiring extremely weak light spectral detection and ultraviolet spectral analysis.
• High sensitivity, low detection limit, excellent spectral stability and reproducibility.

Near-infrared spectrometer

• Near-infrared high-speed InGaAs detector
• -20°C thermoelectric cooling, low dark noise
• Widely used in biomedicine, food, agriculture, and semiconductors
• Three wideband configurations are available: 900 ~ 1700 nm, 900 ~ 2200 nm, and 900 ~ 2500 nm.

In addition to spectrometers, Dimension-Labs also offers a wide range of supporting spectral light sources, optical fibers and probes, measurement stands, sampling accessories, and other spectral measurement devices and complete application solutions to meet your diverse application needs across various industries.