Laser Scanning Digital Camera (LSDC)

Aeon Imaging has developed the Laser Scanning Digital Camera (LSDC), a low-cost, easy to use device which records images of the back of the eye. The LSDC is a confocal line-scanning laser ophthalmoscope, protected by US patents and international patents pending.

The LSDC is not an FDA approved device. Please contact us if you'd like to use the LSDC for research.

Laser Scanning Digital Camera (LSDC)

Capabilities

Multiply Scattered Imaging Mode

Aeon's novel use of the CMOS electronic rolling shutter means that the LS­DC can finely ad­just the off­set of its con­focal aper­ture with re­spect to the il­lu­min­a­tion light on the ret­ina elec­tron­ic­ally in real-time. With a con­focal aper­ture off­set, the LS­DC re­cords im­ages com­posed of mul­tiply scattered light from the deep­er lay­ers of the ret­ina, while re­ject­ing the much stronger dir­ect backs­cat­ter from su­per­fi­cial lay­ers. The res­ult is in­creased sens­it­iv­ity to scat­ter­ing de­fects such as drusen and to the pres­ence of ed­ema.

Retinal images taken of a 60 year old Caucasi­an fe­male sub­ject with dry age-re­lated mac­u­lar de­gen­er­a­tion and wide­spread hard drusen are shown below. A 20-frame av­er­aged stand­ard LS­DC im­age is shown on the left, and a 20-frame av­er­aged mul­tiply scattered mode on the right. Stand­ard and mul­tiply scattered im­age frames were al­tern­ately ac­quired.

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Confocal LSDC image, showing typical superficial detail of the retina. The strong superficial back scattering masks the structure from the deeper layers in the retina.

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Multiply scattered light image of the same eye. Dozens of small scattering disruptions (drusen) appear, which are a clinical hallmark of age-related macular degeneration (AMD).

Refraction Using Structured Illumination Mode

The LS­DC's il­lu­min­a­tion source is more com­monly used in tele­com­mu­nic­a­tion ap­plic­a­tions that re­quire in­tens­ity mod­u­la­tion. In struc­tured il­lu­min­a­tion mode, the source is mod­u­lated while ima­ging, pro­du­cing a se­quence of stripes across the im­age. The con­trast or amp­litude of the stripes meas­ured through-fo­cus provides a loc­al­ized point-spread func­tion. When meas­ured near the fo­vea, this mode provides auto-fo­cus; when com­bined with peri­pher­al point-spread func­tion meas­ure­ments, the to­po­graphy of the fo­cused light on the ret­ina can be re­con­struc­ted. Com­mon uses for to­po­graphy in­clude mod­el­ing peri­pher­al re­frac­tion and de­tect­ing ret­in­al thick­en­ing com­monly as­so­ci­ated with eye dis­ease.

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LSDC image of a 23 year old Caucasian male with structured illumination. Tip: Try looking at the image up close and farther away. At farther distances, your eye will better average out the stripes, providing a clearer view of the retina."

Funding support for the development and evaluation of the LSDC has been provided by the National Institutes of Health Small Business Innovation Research program under grants R44EY020017 and R44EY018772. Matching grant support has also been provided by the Indiana Economic Development Corporation.