Topic
Chromatic scale
About: Chromatic scale is a research topic. Over the lifetime, 4262 publications have been published within this topic receiving 68073 citations.
Papers published on a yearly basis
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Papers
TL;DR: Results show that, at low spatial frequencies below 0.5 cycles/deg, contrast sensitivity is greater to the chromatic gratings, consisting of two monochrome gratings added in antiphase, than to either monochromatic grating alone.
Abstract: A method of producing red-green and blue-yellow sinusoidal chromatic gratings is used which permits the correction of all chromatic aberrations. A quantitative criterion is adopted to choose the intensity match of the two colours in the stimulus: this is the intensity ratio at which contrast sensitivity for the chromatic grating differs most from the contrast sensitivity for a monochromatic luminance grating. Results show that this intensity match varies with spatial frequency and does not necessarily correspond to a luminance match between the colours. Contrast sensitivities to the chromatic gratings at the criterion intensity match are measured as a function of spatial frequency, using field sizes ranging from 2 to 23 deg. Both blue-yellow and red-green contrast sensitivity functions have similar low-pass characteristics, with no low-frequency attenuation even at low frequencies below 0.1 cycles/deg. These functions indicate that the limiting acuities based on red-green and blue-yellow colour discriminations are similar at 11 or 12 cycles/deg. Comparisons between contrast sensitivity functions for the chromatic and monochromatic gratings are made at the same mean luminances. Results show that, at low spatial frequencies below 0.5 cycles/deg, contrast sensitivity is greater to the chromatic gratings, consisting of two monochromatic gratings added in antiphase, than to either monochromatic grating alone. Above 0.5 cycles/deg, contrast sensitivity is greater to monochromatic than to chromatic gratings.
1,066 citations
868 citations
TL;DR: The data suggest strongly that the cells of the M-pathway form the physiological substrate for detection of luminance modulation and the Cells of the P- pathway the substrate for Detection of chromatic modulation, however, at high light levels, intrusion of a so-called luminance mechanism near 10 Hz in psychophysical detection ofchromatic modulation is probably due to responses in the M -pathway.
Abstract: We measured the sensitivity of macaque ganglion cells to luminance and chromatic sinusoidal modulation Phasic ganglion cells of the magnocellular pathway (M-pathway) were the more sensitive to luminance modulation, and tonic ganglion cells of the parvocellular pathway (P-pathway) were more sensitive to chromatic modulation With decreasing retinal illuminance, phasic ganglion cells' temporal sensitivity to luminance modulation changed in a manner that paralleled psychophysical data The same was true for tonic cells and chromatic modulation Taken together, the data suggest strongly that the cells of the M-pathway form the physiological substrate for detection of luminance modulation and the cells of the P-pathway the substrate for detection of chromatic modulation However, at high light levels, intrusion of a so-called luminance mechanism near 10 Hz in psychophysical detection of chromatic modulation is probably due to responses in the M-pathway, arising primarily from a nonlinearity of cone summation Both phasic and tonic ganglion cells responded to frequencies higher than can be psychophysically detected This suggests that central mechanisms, acting as low-pass filters, modify these cells' signals, though the corner frequency is lower for the P-pathway than for the M-pathway For both cell types, the response phase at different frequencies was consistent with the cells' description as linear filters with a fixed time delay
527 citations
TL;DR: The average spherical aberration of the actual eye is predicted without any shape fitting by introducing recent experimental average measurements of cornea and lens into the Gullstrand-Le Grand model.
Abstract: We consider a schematic human eye with four centered aspheric surfaces. We show that by introducing recent experimental average measurements of cornea and lens into the Gullstrand-Le Grand model, the average spherical aberration of the actual eye is predicted without any shape fitting. The chromatic dispersions are adjusted to fit the experimentally observed chromatic aberration of the eye. The polychromatic point-spread function and modulation transfer function are calculated for several pupil diameters and show good agreement with previous experimental results. Finally, from this schematic eye an accommodation-dependent model is proposed that reproduces the increment of refractive power of the eye during accommodation. The variation of asphericity with accommodation is also introduced in the model and the resulting optical performance studied.
514 citations
457 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2026 | 2 |
| 2025 | 240 |
| 2024 | 366 |
| 2023 | 404 |
| 2022 | 723 |
| 2021 | 167 |