Thermal diffusivity measuring device

A thermal diffusivity measuring device, comprising:

• a sample holder for accommodating a sample to be measured,
• a light source designed to emit a pulse of light of a predetermined impulse energy,
• an optical system for directing the pulse of light in a light path onto the sample,
• an infrared sensor configured for a time-dependent detection of an infrared radiation intensity emitted by the sample,
• a calculator-controller for calculating a thermal diffusivity of the sample,
• a continuous wave laser designed to emit an intensity-modulated laser beam, wherein the intensity-modulated laser beam has an intensity that is modulated with an intensity modulation frequency, and wherein the intensity modulated laser beam is emitted along the light path onto the sample,
• wherein the calculator-controller is designed to automatically calculate the thermal diffusivity of the sample on the basis of the time-dependent detection of the infrared radiation intensity and the intensity modulation frequency, and
• a sample changer, wherein the sample holder comprises a first sample holder and at least one second sample holder, and where in the sample changer comprises both the first sample holder and the at least one second sample holder, and wherein the calculator-controller is configured to automatically carry out a method comprising:
• (i) measuring a thermal diffusivity of a first sample held by the first sample holder using the intensity-modulated laser beam or the pulse of light,
• (ii) controlling the sample changer so that at least one second sample held by the least one second sample holder is brought into the light path,
• (iii) measuring the thermal diffusivity of the at least one second sample using the intensity-modulated laser beam or the pulse of light used in step (i), and
• (iv) subsequently measuring the thermal diffusivity of the first sample and the at least one second sample using the intensity-modulated laser beam or the pulse of light, whichever was not used in step (i).

A thermal diffusivity measuring device, comprising:

• a sample holder for accommodating a sample to be measured,
• a light source designed to emit a pulse of light of a predetermined impulse energy,
• an optical system for directing the pulse of light in a light path onto the sample,
• an infrared sensor configured for a time-dependent detection of an infrared radiation intensity emitted by the sample,
• a calculator-controller for calculating a thermal diffusivity of the sample,
• a continuous wave laser designed to emit an intensity-modulated laser beam, wherein the intensity-modulated laser beam has an intensity that is modulated with an intensity modulation frequency, and wherein the intensity modulated laser beam is emitted along the light path onto the sample,
• wherein the calculator-controller is designed to automatically calculate the thermal diffusivity of the sample on the basis of the time-dependent detection of the infrared radiation intensity and the intensity modulation frequency, and
• a furnace designed to set at least a first predetermined temperature and a second predetermined temperature different from the first predetermined temperature,
• wherein the sample holder is arranged in the furnace,
• wherein the calculator-controller is configured to automatically carry out a method comprising:
• (i) controlling the furnace so that the furnace is brought up to the first predetermined temperature,
• (ii) detecting that the furnace is at the first predetermined temperature,
• (iii) at the first predetermined temperature, measuring a first thermal diffusivity and a second thermal diffusivity of the sample in the sample holder respectively using (a) the intensity-modulated laser beam, and (b) the pulse of light,
• (iv) controlling the furnace so that the furnace is brought up to the second predetermined temperature,
• (v) detecting that the furnace is at the second predetermined temperature, and
• (vi) at the second predetermined temperature, measuring a first thermal diffusivity and a second thermal diffusivity of the sample in the sample holder respectively using (a) the intensity-modulated laser beam, and (b) the pulse of light.

A thermal diffusivity measuring device, comprising:

• a sample holder for accommodating a sample to be measured,
• a light source designed to emit a pulse of light of a predetermined impulse energy,
• an optical system for directing the pulse of light in a light path onto the sample,
• an infrared sensor configured for a time-dependent detection of an infrared radiation intensity emitted by the sample,
• a calculator-controller for calculating a thermal diffusivity of the sample,
• a continuous wave laser designed to emit an intensity-modulated laser beam, wherein the intensity-modulated laser beam has an intensity that is modulated with an intensity modulation frequency, and wherein the intensity modulated laser beam is emitted along the light path onto the sample, and
• wherein the calculator-controller is designed to automatically calculate the thermal diffusivity of the sample on the basis of the time-dependent detection of the infrared radiation intensity and the intensity modulation frequency,
• wherein the calculator-controller is configured to automatically carry out a method comprising:
• (a) measuring the thermal diffusivity using a pulse of light to obtain a light pulse thermal diffusivity measured value,
• (b) performing time-resolved measurement of thermal diffusivity using an intensity-modulated laser beam at at least two points to obtain an Angstrom thermal diffusivity measured value, and
• (c) calculating an inhomogeneity parameter that describes an inhomogeneity of the thermal diffusivity of the sample from the light pulse thermal diffusivity measured value and the Angstrom thermal diffusivity measured values.

A thermal diffusivity measuring device, comprising:

• a sample holder for accommodating a sample to be measured,
• a light source designed to emit a pulse of light of a predetermined impulse energy,
• an optical system for directing the pulse of light in a light path onto the sample,
• an infrared sensor configured for a time-dependent detection of an infrared radiation intensity emitted by the sample,
• a calculator-controller for calculating a thermal diffusivity of the sample,
• a continuous wave laser designed to emit an intensity-modulated laser beam, wherein the intensity-modulated laser beam has an intensity that is modulated with an intensity modulation frequency, and wherein the intensity modulated laser beam is emitted along the light path onto the sample, and
• wherein the calculator-controller is designed to automatically calculate the thermal diffusivity of the sample on the basis of the time-dependent detection of the infrared radiation intensity and the intensity modulation frequency,
• wherein the sample comprises two or more samples, and wherein the sample holder is designed to position the two or more samples in two positional degrees of freedom transverse to an optical axis of the infrared sensor.

A thermal diffusivity measuring device, comprising:

• a sample holder for accommodating a sample to be measured,
• a light source designed to emit a pulse of light of a predetermined impulse energy,
• an optical system for directing the pulse of light in a light path onto the sample,
• an infrared sensor configured for a time-dependent detection of an infrared radiation intensity emitted by the sample,
• a calculator-controller for calculating a thermal diffusivity of the sample,
• a continuous wave laser designed to emit an intensity-modulated laser beam, wherein the intensity-modulated laser beam has an intensity that is modulated with an intensity modulation frequency, and wherein the intensity modulated laser beam is emitted along the light path onto the sample, and
• wherein the calculator-controller is designed to automatically calculate the thermal diffusivity of the sample on the basis of the time-dependent detection of the infrared radiation intensity and the intensity modulation frequency,
• wherein the optical system is designed to displace the light path transverse to an optical axis of the infrared sensor so that one or more lateral offsets between the optical axis of the infrared sensor and a strike point of the laser beam are adjustable.