In this paper, we introduce a digital holographic camera objective based on conventional customer... more In this paper, we introduce a digital holographic camera objective based on conventional customer-oriented components for off-axis external white light illumination. The interferometric module based on a modified common-path point diffraction interferometer provides a direct view of the system and admits self-reference and self-interference operation modes. The proposed system is designed for self-emitting and reflective samples. Its modular assemblage provides easy scalability and up-grade possibilities. The operability of the suggested camera system has been proven for both coherent and low-coherent broadband sources, and reconstructed amplitude and phase information of test samples under white light illumination is presented.
Digitale Transmissionsholographie wird für einen schnellen, hochpräzisen und zerstörungsfreien An... more Digitale Transmissionsholographie wird für einen schnellen, hochpräzisen und zerstörungsfreien Ansatz für die Messtechnik und Bildgebung von (halb-)transparenten Proben verwendet. Eine schnelle und anspruchslose Technik zur Korrektur der Verzerrungen des optischen Feldes ist zusätzlich zu den existierenden Lösungen geboten. Der erarbeitete Ansatz verwendet das Hologramm einer Probe selbst - außerhalb des interessierenden Bereiches - als eine Referenz. Die Technik wird mit dem Messprotokoll und dem entsprechenden Algorithmus zur Datenauswertung vervollständigt. Ein entsprechendes optisches System von hoher Stabilität und Universalität wird auf der Basis eines Interferometers mit modifizierter Mach-Zehnder-Geometrie aufgebaut und gewährleistet eine Phasensensitivität von weniger als 1 Grad. Um die Leistungsfähigkeit der vorgeschlagenen Methode festzulegen, wurde eine Reihe von verschiedenen Proben und Effekten holographisch abgebildet beziehungsweise verfolgt.
In this paper we report on practical investigations aimed at failure detection of the integrated ... more In this paper we report on practical investigations aimed at failure detection of the integrated optical circuits (IOC) on Silicon substrate during the control measurements of the items in use. Experiments are performed with a near-infrared (1064 nm) digital holographic microscope (≈90×magnification) in transmission mode. The instrument provides non-destructive and fast (<380 ms reconstruction time for 4112×3008 pixels images) data analysis at the diffraction-limited accuracy (lateral resolution of 760 nm). High quality of the instrument performance is shown on example of topography reconstruction of a standard glass-substrate test target. Practical applicability of the approach was proven on example of diffractive input elements of the IOCs designed for sensing purposes.
We present spatially resolved measurements of the below-band-gap carrier-induced absorption and c... more We present spatially resolved measurements of the below-band-gap carrier-induced absorption and concurrent phase change in a semiconductor with the help of transmission digital holography. The application is demonstrated for a bulk GaAs sample, while the holograms are recorded with a conventional CMOS sensor. We show that the phase information enables spatially resolved monitoring of excess carrier distributions. Based on that, we discuss a phase-based approach for separation of carrier and heat related effects in the semiconductor optical response.
In this paper, we propose a direct-view digital holographic camera system consisting mostly of cu... more In this paper, we propose a direct-view digital holographic camera system consisting mostly of customer-oriented components. The camera system is based on standard photographic units such as camera sensor and objective and is adapted to operate under off-axis external white-light illumination. The common-path geometry of the holographic module of the system ensures direct-view operation. The system can operate in both self-reference and self-interference modes. As a proof of system operability, we present reconstructed amplitude and phase information of a test sample.
In this paper we discuss a near real time digital holographic imaging algorithm achieving ∼4 fps ... more In this paper we discuss a near real time digital holographic imaging algorithm achieving ∼4 fps operation speed on a common central processing unit. The hologram recording is performed in the off-axis geometry in the transmission mode. The algorithm follows a standard angular spectrum method routine and utilizes experimental calibration of the optical instrument for aberration correction. The main limiting factor is related to the size of the initial hologram and its Fourier transform (∼57% of the total execution duration). The performance of the approach is tested on different transparent and semi-transparent samples for reconstruction of sample topography and object in-depth allocation.
In this paper, we introduce a digital holographic camera objective based on conventional customer... more In this paper, we introduce a digital holographic camera objective based on conventional customer-oriented components for off-axis external white light illumination. The interferometric module based on a modified common-path point diffraction interferometer provides a direct view of the system and admits self-reference and self-interference operation modes. The proposed system is designed for self-emitting and reflective samples. Its modular assemblage provides easy scalability and up-grade possibilities. The operability of the suggested camera system has been proven for both coherent and low-coherent broadband sources, and reconstructed amplitude and phase information of test samples under white light illumination is presented.
Digital Holography and Three-Dimensional Imaging 2019, 2019
In this paper we discuss capabilities of the digital holography for rapid inspection. We consider... more In this paper we discuss capabilities of the digital holography for rapid inspection. We consider the case of a transmission mode off-axis configuration and compare its performance with a reference non-optical metrological method.
In this paper, we analyse the capabilities of the digital holographic approach for evaluation of ... more In this paper, we analyse the capabilities of the digital holographic approach for evaluation of the refractive index distribution appearing in semiconductor materials due to external optical excitation. The study is based on a modified transmission Mach-Zehnder holographic microscope operating in the near-infrared spectral range. Practical considerations for holographic characterization of semiconductor samples are discussed. Experimentally measured data are compared with simulations as well as approaches to interpretation of the retrieved data are covered.
We report the generation of shock waves in a disperse medium with absorbing particles of black pi... more We report the generation of shock waves in a disperse medium with absorbing particles of black pigment in the water using continuous laser radiation. As a result of the experimental investigation it was found that the illuminating beam diameter growth at the constant laser power results in the decrease of the signals&amp;amp;amp;amp;amp;amp;#39; modulation frequencies, improving their stability and increasing their amplitudes. In turn, the decrease of the signal&amp;amp;amp;amp;amp;amp;#39;s modulation frequency is caused by the growth of time, which is needed for heating the medium to the critical temperature of cavitation. Improving the stability and the increase of optical and acoustic signal amplitudes take place, due to the growth of the medium volume and hence the number of pigment particles that participate in cavitation.
In this paper, we introduce a digital holographic camera objective based on conventional customer... more In this paper, we introduce a digital holographic camera objective based on conventional customer-oriented components for off-axis external white light illumination. The interferometric module based on a modified common-path point diffraction interferometer provides a direct view of the system and admits self-reference and self-interference operation modes. The proposed system is designed for self-emitting and reflective samples. Its modular assemblage provides easy scalability and up-grade possibilities. The operability of the suggested camera system has been proven for both coherent and low-coherent broadband sources, and reconstructed amplitude and phase information of test samples under white light illumination is presented.
Digitale Transmissionsholographie wird für einen schnellen, hochpräzisen und zerstörungsfreien An... more Digitale Transmissionsholographie wird für einen schnellen, hochpräzisen und zerstörungsfreien Ansatz für die Messtechnik und Bildgebung von (halb-)transparenten Proben verwendet. Eine schnelle und anspruchslose Technik zur Korrektur der Verzerrungen des optischen Feldes ist zusätzlich zu den existierenden Lösungen geboten. Der erarbeitete Ansatz verwendet das Hologramm einer Probe selbst - außerhalb des interessierenden Bereiches - als eine Referenz. Die Technik wird mit dem Messprotokoll und dem entsprechenden Algorithmus zur Datenauswertung vervollständigt. Ein entsprechendes optisches System von hoher Stabilität und Universalität wird auf der Basis eines Interferometers mit modifizierter Mach-Zehnder-Geometrie aufgebaut und gewährleistet eine Phasensensitivität von weniger als 1 Grad. Um die Leistungsfähigkeit der vorgeschlagenen Methode festzulegen, wurde eine Reihe von verschiedenen Proben und Effekten holographisch abgebildet beziehungsweise verfolgt.
In this paper we report on practical investigations aimed at failure detection of the integrated ... more In this paper we report on practical investigations aimed at failure detection of the integrated optical circuits (IOC) on Silicon substrate during the control measurements of the items in use. Experiments are performed with a near-infrared (1064 nm) digital holographic microscope (≈90×magnification) in transmission mode. The instrument provides non-destructive and fast (<380 ms reconstruction time for 4112×3008 pixels images) data analysis at the diffraction-limited accuracy (lateral resolution of 760 nm). High quality of the instrument performance is shown on example of topography reconstruction of a standard glass-substrate test target. Practical applicability of the approach was proven on example of diffractive input elements of the IOCs designed for sensing purposes.
We present spatially resolved measurements of the below-band-gap carrier-induced absorption and c... more We present spatially resolved measurements of the below-band-gap carrier-induced absorption and concurrent phase change in a semiconductor with the help of transmission digital holography. The application is demonstrated for a bulk GaAs sample, while the holograms are recorded with a conventional CMOS sensor. We show that the phase information enables spatially resolved monitoring of excess carrier distributions. Based on that, we discuss a phase-based approach for separation of carrier and heat related effects in the semiconductor optical response.
In this paper, we propose a direct-view digital holographic camera system consisting mostly of cu... more In this paper, we propose a direct-view digital holographic camera system consisting mostly of customer-oriented components. The camera system is based on standard photographic units such as camera sensor and objective and is adapted to operate under off-axis external white-light illumination. The common-path geometry of the holographic module of the system ensures direct-view operation. The system can operate in both self-reference and self-interference modes. As a proof of system operability, we present reconstructed amplitude and phase information of a test sample.
In this paper we discuss a near real time digital holographic imaging algorithm achieving ∼4 fps ... more In this paper we discuss a near real time digital holographic imaging algorithm achieving ∼4 fps operation speed on a common central processing unit. The hologram recording is performed in the off-axis geometry in the transmission mode. The algorithm follows a standard angular spectrum method routine and utilizes experimental calibration of the optical instrument for aberration correction. The main limiting factor is related to the size of the initial hologram and its Fourier transform (∼57% of the total execution duration). The performance of the approach is tested on different transparent and semi-transparent samples for reconstruction of sample topography and object in-depth allocation.
In this paper, we introduce a digital holographic camera objective based on conventional customer... more In this paper, we introduce a digital holographic camera objective based on conventional customer-oriented components for off-axis external white light illumination. The interferometric module based on a modified common-path point diffraction interferometer provides a direct view of the system and admits self-reference and self-interference operation modes. The proposed system is designed for self-emitting and reflective samples. Its modular assemblage provides easy scalability and up-grade possibilities. The operability of the suggested camera system has been proven for both coherent and low-coherent broadband sources, and reconstructed amplitude and phase information of test samples under white light illumination is presented.
Digital Holography and Three-Dimensional Imaging 2019, 2019
In this paper we discuss capabilities of the digital holography for rapid inspection. We consider... more In this paper we discuss capabilities of the digital holography for rapid inspection. We consider the case of a transmission mode off-axis configuration and compare its performance with a reference non-optical metrological method.
In this paper, we analyse the capabilities of the digital holographic approach for evaluation of ... more In this paper, we analyse the capabilities of the digital holographic approach for evaluation of the refractive index distribution appearing in semiconductor materials due to external optical excitation. The study is based on a modified transmission Mach-Zehnder holographic microscope operating in the near-infrared spectral range. Practical considerations for holographic characterization of semiconductor samples are discussed. Experimentally measured data are compared with simulations as well as approaches to interpretation of the retrieved data are covered.
We report the generation of shock waves in a disperse medium with absorbing particles of black pi... more We report the generation of shock waves in a disperse medium with absorbing particles of black pigment in the water using continuous laser radiation. As a result of the experimental investigation it was found that the illuminating beam diameter growth at the constant laser power results in the decrease of the signals&amp;amp;amp;amp;amp;amp;#39; modulation frequencies, improving their stability and increasing their amplitudes. In turn, the decrease of the signal&amp;amp;amp;amp;amp;amp;#39;s modulation frequency is caused by the growth of time, which is needed for heating the medium to the critical temperature of cavitation. Improving the stability and the increase of optical and acoustic signal amplitudes take place, due to the growth of the medium volume and hence the number of pigment particles that participate in cavitation.
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Papers by Vira Besaga