VSC-200 Video Spectral Comparator is a device mainly used for identifying alterations, covering up, fading, forgery, adding strokes, handwriting indentation, anti-counterfeiting hidden marks, etc. of documents, receipts and files. VSC-200 Video Spectral Comparator includes host, CCD camera and criminal investigation image processing software.

1. Light source system

Uniform strong light source: 1* 24V/150W tungsten halogen lamp, equipped with a dedicated cooling fan, condenser lens, and heat-insulating glass.

UV long wave: 365nm: 1* 10W, for visible fluorescence observation.

Visible side light: 1* 12V/50W LED lamp, capable of detecting infrared absorption and reflection, with angel adjustable lamp holder, for detecting indentation.

Perspective white light lamp: 2* 20W, capable of detecting watermarks.

Excitation filters for visible light sources: using high transmittance, narrow half width bandpass filters at 000nm, 365nm, 440nm, 530nm, 555nm, 585nm and 615nm.

Reception filters: 000nm, 450nm, 565nm, 700nm, 720nm, 800nm and 900nm cut-off long wave pass filters.

2. Image system

The high-sensitivity camera: a 1/3” CCD color camera with a resolution of 800 TV lines and a sensitivity of 0.0001 Lux. High resolution and sensitivity for both near-infrared and visible light spectral ranges.

Motorized zoom lens: The relative aperture of lens is 1.2. The aperture, focusing, and zoom magnification (1X-30X) are all electrically adjustable.

3. Image processing software

The storage/printing function: it can store all images and data obtained by the video spectral comparator during the inspection process, and can be used in conjunction with a printer to print out the required images.

The comparison function: it can perform horizontal and vertical stitching or overlapping comparison between two detected images. Static and dynamic images can be compared in real-time.

Gray value measurement: it can measure the gray value of any specified point or area in the image. And the grayscale changes at that location under various detection conditions can be displayed in the form of curves. This method is particularly advantageous for identifying subtle grayscale differences between different texts in the image formed by the inspected document that are difficult for the human eye to detect.

Depth of field automatic synthesis

Processing Blurred image

Motion blur processing, geometric correction of deformed images and fast image processing

Other image processing: It can do reflectivity and absorbance measurement, image measurement and annotation, extraction of the main part of the stamps, curve and linear image shaping, universal cutting comparison, image ghosting and other various image processing methods.

4. Main function

Multiple excitation light and receiving filter combinations are used to test the fluorescence differences of different inks.

The combination of reflective light source and receiving filter is used to test the absorption and reflection differences to different wavelength bands of light of different inks.

The combination of reflective light source and receiving filter is used to test the penetration effect to different infrared light bands of different inks.

The combination of transmitted light source and receiving filter is used to test the penetration effect to different infrared light bands of different inks.

The side light source illuminates the document in a grazing incidence manner to inspect the scratch and cutting marks on the document.

The transmitted light source illuminates the document from below upwards to inspect the traces of cutting and patching on the document.

VSC-200 is mainly used for identifying alterations, covering up, fading, forgery, adding strokes, handwriting indentation, anti-counterfeiting hidden marks, etc. of documents, receipts and files. It is an ideal choice for Public Security Bureaus, procuratorates, courts and their colleges.

Fading Handwriting

Handwriting Observation

Cover up Handwriting

Adding Handwriting