IRLabs is the global leader in highly sensitive and cost-effective cryogen-free and cryogenic bolometers and IR detectors for general research, high resolution and far-IR detection, and OEM applications.

Find the Bolometer or Photoconductor for Your Spectral Range

Bolometers and IR detector comparison table

Why Choose Bolometers from IRLabs?

We have supplied cooled IR bolometers and IR detectors to leading scientific organizations since 1967. We offer a full range of composite, silicon, hot electron, and germanium bolometers and photodetectors used for FTIR spectroscopy, high magnetic field research, terahertz research, molecular beam physics, and IR astronomy.

Highly sensitive: Our proven experience in cryogenics, electronics and optics sets the benchmark in sensitivity

Cost effective: Standard bolometers reduce project costs

Cryogen-free options: Eliminates needs for scarce and expensive liquid helium

Wide spectral range: Complete coverage of the IR spectral range

Customized configurations: Can be configured to meet specific application requirements including increased work height, dual detectors, filter positions and coupling optics

Bolometer & IR Detector Comparison


Spectral Response (µm)

Operating Temp
Electrical Sensitivity (S[V/W])Noise Equivalent Power
Frequency Response
(Optimum Chopping Frequency)
Liquid Cryogen Cooling

Cryogen-free Cooling

General Purpose 4.2 K Bolometer System

15 – 2000

operation to 4.2~ 2.4 X 105~ 2.5 X 10-13≤ 80 at 80Hz< 500 Hz  
Hi Res 4.2K Bolometer System

15 – 500

operation to 4.2~ 6.1 X 105~ 6.5 X 10-14≤ 40 at 80Hz< 200 Hz  
Standard 1.6 K Bolometer System

15 – 2000

1.6~ 7.5 X 105~ 4.6 X 10-14≤ 40 at 80Hz> 1 KHz  
Far-IR 1.6 K Bolometer System

300 – 5000

1.6~ 1.0 X 107~ 2.0 X 10-14≤ 50 at 80Hz< 300 Hz  

InSb Hot e-Bolometer

0.3mm – 5mm

4.2> 4.0 X 103 < 8 x 10-13< 4.0 at 200Hz< 600 kHz  
Si:B Photoconductor5 – 304.2SNR > 2.5 X 105< 5.0 X 10-12< 20µV/Hz(1/2) at 1kHzDC to 5kHz  
Ge:Ga Photoconductor40-1204.2SNR > 2.5 X 105< 5.0 X 10-11< 10µV/Hz(1/2) at 1kHzDC to 5kHz  

Selecting Bolometers or Photoconductors

Our broad-bandwidth bolometers and doped photoconductors each offer advantages to best meet your spectral band, frequency response, noise, and budget requirements. We’re happy to discuss your application, requirements, and budget to determine the right fit for your needs.

Cryogenic Bolometer


  • Broadest spectral range from LWIR to THz
  • Low signal-to-noise ratio
  • Cryogenic or cryogen-free cooling


Photoconductor Systems

  • Spectral range from MWIR to far IR
  • Faster response times
  • Cryogenic or cryogen-free cooling

Selecting Liquid Cryogenic or Cryogen-Free Cooling

All detector types are cooled to cryogenic temperatures to reduce noise and increase sensitivity. Detectors can be cooled using pour-filled liquid cryogen dewars or cryogen-free mechanical refrigeration. 

Cryogenic Bolometers

Liquid Cryogenic Cooling

Liquid cryogen dewars are compact with no moving parts, easy to use, and have a lower initial cost. Recommended for simple, reliable operation:

  • Use LN2 and LHe
  • Simple, compact cooling solution
  • Lower cost of equipment
  • No mechanical noise and vibration
  • No bulky compressor and hoses
  • High reliability

Cryogen-free Bolometer

Cryogen-Free Cooling

Refrigerated systems are larger, more complex, and have a higher initial cost but eliminate the expense of refilling cryogens. Recommended for cost-effective, continuous unattended cold operation:

  • Uses mechanical refrigeration
  • No expensive LHe
  • Continuous operation with no refilling required
  • Reliable; no unexpected warmups
  • Acceptably low vibration in most cases

Customize to Meet Your Unique Specifications

IRLabs offers a variety of standard optical components for integration on your bolometer or IR detector system.

Optical, Mechanical and Cryo/Vacuum Accessories

IRLabs offers a variety of standard optical components for integration on your IR detector system.