Jean-Claude Simon

The A2iA Intercheque System: Courtesy Amount and Legal Amount Recognition for French Checks

We developed a check reading system, termed INTERCHEQUE, which recognizes both the legal (LAR) and the courtesy amount (CAR) on bank checks. The version presented here is designed for the recognition of French, omni-bank, omni-scriptor, handwritten bank checks, and meets industrial requirements, such as high processing speed, robustness, and extremely low error rates. We give an overview of our recognition system and discuss some of the pattern recognition techniques used. We also describe an installation which processes of the order of 70,000 checks per day. Results on a data base of about 170,000 checks show a recognition rate of about 75% for an error rate of the order of 1/10,000 checks.

A2iA Check Reader: a family of bank check recognition systems

The paper presents new A2iA bank check recognition systems designed to process handwritten and/or printed checks issued in France, UK or USA. All the systems have identical architecture and design principles. However, each of them contains a country-specific part and is trained with country-specific data. Each system performs location, extraction, segmentation and recognition of courtesy and legal amounts in a document image, as well as deciding whether to accept or reject the check. The recognition rate is 80-90%. In the production mode, the check acceptance rate is 60-75%, with the misread rate corresponding to that of a human operator (close to 1%).

Gain recovery dynamics in semiconductor optical amplifier

We develop a time-domain model for gain recovery dynamics in a semiconductor optical amplifier (SOA). This model allows to explain the gain overshoot which can be observed in the temporal dynamics of SOA gain after the crossing of a short saturating pump pulse. We show the good agreement between experimental and numerical results.

Regularities and Singularities in Line Pictures

The main difficulty of Pattern Recognition is the interpretation of the iconic picture, the pixels, into primitive features. The interest of a feature classification as “regular” and “singular” is recalled and justified. These ideas are applied to line images, and particularly to handwritten words. On the graph representation of a word, a regular feature, the “axis,” is found; it allows to segment the word representation and to obtain a descriptive chain. Examples of such symbolic descriptions are given, with their interpretation as a word among a list of 25 words. The results are of the order of 87% success, 3% substitution on one handwriting. Preliminary results show that it may be extended to large categories of handwriting.

Efficient second harmonic generation in nanophotonic waveguides for optical signal processing

We report very efficient second harmonic generation in membrane photonic crystal waveguide. The combination of absorption-free material and slow-light enhancement enables a large harmonic generation efficiency. A peak pump power of about 450u2009mW generates up to 45u2009μW peak second harmonic power over a broad spectral range. The signal is exploited to demonstrate optical performance monitoring of data at 42u2009Gb/s.

Monolithic Integrated Slot-Blocker for High Datarate Coherent Optical Slot Switched Networks

Recent progresses on monolithic SOI-based integration are presented for achieving high-performance slot-blocker for cost-sensitive metropolitan and datacenter networks. We review several nodes architectures for such optical slot switching ring networks. Such devices integrate up to 65 functional elements, allowing complex operations such as polarization and wavelength (de)multiplexing with sub-wavelength switching capability. Compact footprint, fast switching time (below 10 ns) as well as high extinction ratio (more than 20 dB) are demonstrated. We demonstrate the fast add/drop operation of advanced modulation formats (56/80 Gbit/s SP-QPSK, 128 Gbit/s PDM-QPSK, 256 Gbit/s PDM-16QAM, and 320 Gbit/s PDM-32QAM) using three generations of integrated slot-blockers.

Silicon-on-Insulator RF Filter Based on Photonic Crystal Functions for Channel Equalization

A compact silicon-on-insulator two-tap interferometer is demonstrated as a channel equalizer. The radiofrequency filter is reconfigurable thanks to thermally controlled photonic crystal couplers and delay lines. The channel fading of a dispersive fiber link supporting a directly modulated telecommunication signal is successfully compensated for using the interferometer, leading to eye diagram opening and the possibility to recover the bit-error-rate of a reference signal with less than 1-dB power penalty.

Monolithic integrated reflective polarization diversity SOI-based slot-blocker for fast reconfigurable 128 Gb/s and 256 Gb/s optical networks

We demonstrate a novel fully integrated, silicon-on-insulator, 16-channel polarization diversity fast reflective slot-blocker with nanosecond switching time, integrating more than 65 functional elements. Its suitability for use in reconfigurable metropolitan networks is assessed.

Efficient non-collinear second harmonic generation in photonic crystal waveguides

Using a 1-mm long photonic crystal waveguide made of Gallium Indium Phosphide, we generate a peak second harmonic power of 45 μW, which correspond to a conversion efficiency of 210^-4W^-1.

Efficient second harmonic generation in photonic crystal waveguides for optical performance monitoring in the full C-band at 42.5 Gb/s

We demonstrate 20 μW second harmonic generation in a photonic crystal waveguide. The collected signal has been used for optical performance monitoring of the chromatic dispersion and optical signal to noise ratio of a 42.5 Gb/s Return to Zero signal all over the C-band.