Optical absorption spectrometer

An optical absorbance spectrometer comprising:

• a sample housing configured to hold a sample and comprising a light in-coupling region and a light out-coupling region, wherein the light in-coupling region and the light out-coupling region are located on a same external side of the sample housing such that both are accessible from a common direction external to the sample housing;
• a light source configured to emit broadband light into the light in-coupling region of the sample housing;
• one or more reflectors configured to reflect the light such that the light passes through a sample holding volume of the sample housing multiple times;
• a sensor arranged to receive the light from the light out-coupling region of the sample housing, after the reflections;
• wherein the sensor comprises a plurality of detectors configured to detect an intensity of the received light at multiple different wavelengths;
• and
• beam collecting optics arranged between the light out-coupling region and the sensor and comprising a prism with a curved reflecting surface and a lens, the beam collecting optics configured to receive a beam of light that leaves the sample holding volume, and to increase a cross-sectional area of the beam of light before the beam of light is incident upon the sensor,
• wherein the light source is configured to provide a beam of light, and the reflectors are configured to direct the beam of light through the sample holding volume multiple times.