Real-time elimination of Smear noise for large interline transfer area CCD camera

In this paper, the performance of the electronic conventional image motion compensation (IMC) method based on the time delay integration (TDI) mode was analyzed using the optical injection formula of charge coupled devices (CCDs). The result shows that the non-synchronous effect of charge packet transfer caused by line-by-line transfer during exposure makes the compensated image dissatisfying. Then an improved electronic IMC method based on the CCD multiphase structure was proposed. In this method, a series of proper driving clocks were applied to drive the charge packet to move electrode-by-electrode during the exposure time, which results in a minimum non-synchronous effect of charge packet transfer. The mismatch of velocity between charge packet transfer and image motion was decreased. The performance of the improved electronic IMC method was also analyzed using the optical injection formula. The modulation degrees of the two methods were compared. The average value of the modulation degree of the improved electronic IMC method was 47/96, greater than the conventional electronic IMC method, which was 1/3. To achieve the improved electronic IMC, the driver timing diagram of the improved electronic IMC method was proposed. This paper presented an improved hardware implementation method for the improved electronic IMC method. Based on the basic FTF4052M drive circuit system, an IMC pulse pattern generator that worked together with the main pulse pattern generator (SAA8103) was added to achieve the improved electronic IMC. Then, the internal structure of the IMC pulse pattern generator was given. A dual pulse pattern generator drive circuit system was proposed. After computer simulation and indoor real shot verification, the compensation effect of the improved electronic IMC method was better than the compensation effect of the conventional electronic IMC method.

show abstract

“…The improved electronic IMC method can reduce the non-synchronous effect, greatly improving the compensation effect [29]. …”

Section: Improved Electronic Image Motion Compensation (Imc) Methodsmentioning

confidence: 99%

An Improved Electronic Image Motion Compensation (IMC) Method of Aerial Full-Frame-Type Area Array CCD Camera Based on the CCD Multiphase Structure and Hardware Implementation

Ren

Song

et al. 2018

Sensors

View full text Add to dashboard Cite

show abstract

“…Correction algorithms are an attractive alternative to hardware design and electrical processing due to their convenience and applicability for the generated smeared image [19], [20]. Using the optical black area (OBR) [19] and dummy pixel [20] is a comprehensible research direction without the analysis of the causes of the smear effect. The noise can be estimated from the area without a valid light signal, and the smeared image can be effectively corrected through appropriate filters.…”

mentioning

confidence: 99%

Analysis and Correction of Smeared Image From Interline-Transfer CCD in Beam Quality Measurement

et al. 2022

View full text Add to dashboard Cite

The smear effect caused by light penetration of interline-transfer (IT) CCD in beam quality measurement (BQM) is detrimental and not analyzed pertinently. This report proposes a mathematical model and a correction method for the smeared image. The smear noise is fitted and subtracted through its correlation with the light signal obtained from the model and pre-calibration. The application in BQM is presented by measuring beam quality factor M 2 and power in the bucket (PIB). The results verify the validity of the method. An evaluation standard of the correction effect is also recommended. Index Terms-Charge-coupled-device (CCD) image sensor, interline transfer (IT), laser beams. I. INTRODUCTION C CD sensors are widely used in beam quality measurement (BQM) to image the cross-section spot and reproduce its intensity distribution [1], [2], [3], [4]. Interline-transfer (IT) CCD is one of the most typical structures. Its signal charges are transferred from the photodiode to the vertical CCD (V-CCD) after the photosensitivity, then enter the horizontal CCD (H-CCD) for amplification and readout [5]. IT-CCD has a balanced performance in terms of high frame rate, imaging quality and sensitivity [6], [7], [8]. The smear effect is a common error source for IT-CCD, which is caused by light penetration through the light shield on VCCD, light leakage from diffraction, refraction, and waveguide effect on CCD surface, or charge diffusion during signal transfer in V-CCD [9], [10]. Generally, it appears as vertical line noise across the image.

show abstract

Real-time elimination of Smear noise for large interline transfer area CCD camera

Cited by 2 publications

References 0 publications

An Improved Electronic Image Motion Compensation (IMC) Method of Aerial Full-Frame-Type Area Array CCD Camera Based on the CCD Multiphase Structure and Hardware Implementation

An Improved Electronic Image Motion Compensation (IMC) Method of Aerial Full-Frame-Type Area Array CCD Camera Based on the CCD Multiphase Structure and Hardware Implementation

Analysis and Correction of Smeared Image From Interline-Transfer CCD in Beam Quality Measurement

Contact Info

Product

Resources

About